Help KOER Reading Codes

bretamo said:

I haven't pulled codes in my 92GT since I removed the smog pump and decided I should do it today. For the Key On Engine Running test, I pulled more numbers than ever before. Can someone help? Here is the series of numbers pulled after the initial "4" (which signifies that is an 8 cylinder moter) and after what sounds like the WOT test:

Run #1: 1 2 2 3 9 4 4 4 3 3 1 2 2 3 9 4 4 4 3 3

Run #2: 1 2 2 3 4 1 3 3 1 2 2 3 4 1 3 3

I think I need the German's enigma machine to help turn all these numbers into error codes..

Can anyone help me turn these into a error code or two?

Thanks in advance

Click to expand...

run 1= 12 23 94 44 33
run 2= 12 23 41 33

linky= http://www.troublecodes.net/Ford/

I am bored so here you go...






2 Digit Codes

11-System OK

12-Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too low) - ISC

13-ISC did not respond properly (extends to touch throttle then retracts for KOEO) - ISC




(R)


Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)




(M)


ISC sticking, open ITS circuit or TP sticking

14-Ignition pickup (PIP) was erratic - Ignition Systems







E4OD Transmission diesel RPM sensor - Diesel RPM sensor

15-No Keep Alive Memory power to PCM pin 1 or bad PCM (Memory Test Failure)




(M)


KAM (pin 1) was interrupted (was battery disconnected ?)

16





1 9L & 2 5L - Throttle stop set too high - IDLE or Idle Set Procedures







2 3L - RPM's too low - IDLE




(O)


Electronic ignition - IDM circuit fault - Ignition Systems

17





1 9L & 2 5L - Throttle stop set too low - IDLE

18


(R)


Check base timing & advance function - Timing Tests




(M)

Ignition TACH signal erratic - Ignition Systems







Spark Angle Word (SAW) circuit failure (1 9L SFI)

19


(O)


No Vehicle Power (pins 37 + 57) or bad PCM VPWR Diagnosis




(R)


Erratic idle during test (reset throttle & retest) - Idle Set Procedures







Electronic ignition Cylinder ID sensor/circuit problem - Ignition Systems

21





Engine Coolant Temperature (ECT) sensor out of range - ECT

22





MAP (vacuum) or BARO signal out of range - MAP

23





Throttle sensor out of range or throttle set too high - TPS

24





Intake Air Temperature (IAT) or Vane Air Temperature (VAT) sensor out of range - IAT VAT

25





Knock sensor not tested (ignore if not pinging) - KS

26





Mass Air Flow (MAF) or Vane Air Flow (VAF) out of range - MAF VAF







Transmission Oil Temperature (TOT) sensor out of range, Transmissions

27





Vehicle Speed Sensor problem - VSS

28





Vane Air Temperature (VAT) sensor out of range - VAT







2 3L w/Electronic Ignition - Cyl ID, IDM low or right coil pack failure - Ignition Systems

29





Vehicle Speed Sensor problem - VSS

31


(O,R,M)


EVP - EVP signal is/was out of range - EVP




(O,R,M)


EVR - EVP signal is/was low - EVR




(O,R,M)


PFE - PFE signal is/was low - PFE

32


(R)


EVP - EGR not responding properly during test - EVP




(O,R,M)


EVR - EVP signal is/was low - EVR




(R,M)


PFE - PFE shows low pressure, EGR not seating or memory, not seating intermittently - PFE

33


(O,M)


ALL - EGR did not open/ respond during test or if memory code, did not open intermittently - EVP EVR PFE

34


(R)


EVP - EGR did not respond properly during test - EVP




(O,R,M)


EVR - EVP sensor is/was high - EVR




(O,R,M)


PFE - PFE sensor is/was out of range - PFE

35


(R)


EVP - Engine RPM's too low to test EGR system - EVP




(O,R,M)


EVR - EVP sensor signal is/was high - EVR




(O,R,M)


PFE - PFE sensor signal is/was high - PFE

38





Idle Tracking Switch signal was intermittent - ISC

39





Transmission Torque Converter clutch not engaging - Transmissions

41


(R)


System lean - Fuel control




(M)


System was lean for 15 seconds or more (no HO2S switching) - Fuel control

42


(R)


System rich - Fuel control




(M)


System was rich for 15 seconds or more (no HO2S switching) - Fuel control

43


(R)


HO2S sensor not reading (run at 2000 rpm's for 2 minutes and retest - check for HO2S switching)




(M)


Was lean at WOT for 3 seconds or more - Fuel control

44





AIR system inoperative - Air Injection

45





AIR not Diverting (AIRD) - Air Injection







Electronic Ignition - coil primary circuit failure - Ignition Systems

46





AIR Bypass (AIRB) not working - Air Injection







Electronic Ignition - primary circuit failure coil 2 - Ignition Systems

47





Low flow unmetered air (check for small vacuum leaks, injector o'rings, gaskets etc )







E4OD transmission 4x4 switch/circuit problem - Transmissions

48





High flow unmetered air (check for large vacuum leak, inlet hoses etc )







Electronic Ignition - coil primary circuit failure - Ignition Systems

49





Electronic Ignition - spout signal circuit problem - Ignition Systems







Transmission 1/2 shift problem - Transmissions

51





Engine Coolant Temperature (ECT) sensor signal is/was too high - ECT

52





Power Steering Pressure Switch/circuit open - PSP




(R)


Did you turn wheel during test ?

53





Throttle Position sensor too high - TPS

54





Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal high - IAT VAT

55





No or low (under 7 5 V) Key Power to PCM pin 5

56





Vane Air Flow (VAF) or Mass Air Flow (MAF) sensor high - VAF MAF







Transmission Oil Temperature sensor too high - Transmissions

57





Intermittent in Park/Neutral/ Switch or Neutral Pressure switch circuit - PNP or Transmissions

58





Idle Tracking Switch (ITS) signal problem ISC







Vane Air Temperature (VAT) sensor out of range or open - VAT

59





AXOD 4/3 circuit fault - Transmissions







3 0L SHO - Low speed fuel pump circuit problem - Power / Fuel Pump Circuits







Transmission 2/3 shift problem - Transmissions

61





Engine Coolant Temperature (ECT) sensor is or was too low - ECT

62





AXOD (KOEO only) 3/2 circuit short to ground - Transmissions







AXOD (KOEO AND KOER) 4/3 circuit failure - Transmissions







E4OD excessive converter clutch slippage - Transmissions

63





Throttle Position Sensor (TPS) signal too low TPS

64





Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal low or grounded - IAT VAT

65





Check intermittent HO2S (signal or ground) - Fuel Control




(R)


E4OD truck - cycle OD cancel switch after engine ID is received - Transmissions







1984 3 8L ONLY - O, M Battery voltage high (check for electrical system overcharging)

66




Vane Air Flow (VAF) or Mass Air Flow (MAF) signal low - VAF MAF







Transmission Oil Temperature (TOT) signal low (possibly grounded) - Transmissions

67





Park/Neutral circuit fault - PNP







Transmission Manual Lever Position (MLP) sensor circuit - Transmissions




(M)


Intermittent Park Neutral Position (PNP) sensor fault - PNP

68





Idle Tracking Switch (ITS) circuit (possibly grounded) - ISC







Vane Air Temperature (VAT) sensor out of range or grounded - VAT







3 8L AXOD -Transmission Temperature Switch (TTS) open - Transmissions







Electronic Transmission - Transmission Oil Temperature (TOT) sensor was overheated -Transmissions

69





AXOD transmission (O) 3/2 switch closed (possible short circuit) - Transmissions







AXOD (M) 3/2 switch open (poss short to power) - Transmissions







E4OD 3/4 shift problem - Transmissions

70


(M)


3 8L AXOD - Data link to instrument cluster fault Service any other EEC codes, erase memory and retest If code is still present refer to instrument cluster diagnosis manual

71


(M)


1 9L TBI, 2 3L TBI, 2 5L TBI - ITS signal was grounded when throttle should have been opening ITS-ISC ISC motor problem or Idle Tracking Switch (ITS) signal wire shorted to ground - ISC




(M)


1 9L MFI - PCM re-initialized Possible electrical noise, case ground or intermittent VPWR problem - VPWR Diagnosis




(M)


3 8L AXOD - Data link to instrument cluster fault - See code 70

72


(R)


No MAP or MAF change in "goose" test - retest, check for frequency or voltage change - MAP MAF




(M)


1 9L MFI - VPWR circuit to PCM was intermittent - VPWR Diagnosis




(M)


2 3L T/C - PCM re-initialized Possible electrical noise, case ground or intermittent VPWR problem - VPWR Diagnosis




(M)


3 8L AXOD - Message center data link circuit fault - See code 70

73


(O)


Rerun test, if 73 is still output replace TPS




(R)


No Throttle Position Sensor (TPS) change in "goose" test Must get at least 25% throttle rotation - TPS

74





Was brake depressed after engine ID was received ?







Brake On Off (BOO) signal open or short to ground - BOO

75





Brake On Off (BOO) signal shorted to power - BOO

76





Vane Air Flow (VAF) did not respond to "goose" test - VAF

77





System did not receive "goose" test - see TESTS

78


(M)


VPWR circuit to PCM was intermittent or the PCM is bad VPWR Diagnosis

79





A/C is on or pin 10 is shorted to power

81





Boost control solenoid - Solenoids







AIRD solenoid - Solenoids and Air Injection







3 0L SHO - Inlet Air Solenoid - Solenoids

82





2 3L TC - Fan Control wire shorted to ground - A/C and Fan Circuits







AIRB solenoid - Solenoids and Air Injection







3 8L SC - Super Charger Bypass Solenoid - Solenoids

83





High Electro Drive Fan circuit fault - A/C and Fan Circuits







EGR Control solenoid - Solenoids







3 0L SHO - Low Speed Fuel Pump Relay circuit - Power / Fuel Pump Circuits

84





EGR Vacuum Regulator - Solenoids







EGR cutoff solenoid - Solenoids







EGR Vent solenoid - Solenoids

85





2 3L T/C Automatic - 3/4-4/3 Shift solenoid - Transmissions







CANP solenoid (ALL 1989) - Solenoids




(M)


1 9L MFI - System has corrected rich condition - Fuel control

86





2 3L or 2 9L Truck - A4LD 3/4 shift solenoid - Transmissions







(M) 1 9L MFI - System has corrected lean condition - Fuel control

87


(O)


Fuel pump circuit fault (check inertia switch) - Power / Fuel Pump Circuits







Vehicles with 2BBL carb - Temperature Compensated Accelerator Pump Solenoid - Solenoids (M) intermittent in fuel pump primary circuit - Power / Fuel Pump Circuits NOTE: On some Escorts with automatic seat belts this code is normal IN MEMORY due to the wiring

88





Throttle Kicker Solenoid - Solenoids







Variable Voltage Choke relay circuit fault - VVC







Fan Control circuit fault - A/C and Fan Circuits







A4LD - Converter Clutch Override solenoid - Transmissions







Electronic Ignition - IDM, DPI or spout circuit fault - Ignition Systems

89





A4LD - Converter Clutch Override solenoid - Transmissions







AXOD Torque Converter Control solenoid circuit - Transmissions







Exhaust Heat Control (heat riser) solenoid circuit - Solenoids

91

(R, M)


System running lean - Fuel control







Transmission SS 1 circuit/solenoid problem - Transmissions

92


(R)


System running rich - Fuel control







Transmission SS 2 circuit/solenoid problem - Transmissions

93


(O,R)


Throttle linkage binding or bad ISC motor ISC HO2S not reading Fuel control






Transmission TCC circuit/solenoid problem - Transmissions

94





AIR system inoperative - Air Injection







Transmission TCC circuit/solenoid problem - Transmissions

95


(O)


Fuel pump: open, bad ground or always on - Power / Fuel Pump Circuits




(R)


AIR not Diverting (AIRD) - Air Injection




(M)


Possible bad fuel pump ground or open between fuel pump and pin 8 at PCM (Fuel Pump Monitor signal) - Power / Fuel Pump Circuits

96


(O)


Fuel pump monitor circuit shows no power - Power / Fuel Pump Circuits




(R)


AIR Bypass (AIRB) not working - Air Injection




(M)


(Service 87 code first if present) Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits

97





E4OD OD cancel light circuit failure - Transmissions

98


(R)


Did not pass KOEO yet (Get 11 in KOEO first)







Transmission EPC circuit/solenoid failure - Transmissions

99


(R)


ISC needs to learn (Let idle for 2 minutes, Erase memory and retest)







Transmission EPC circuit/solenoid failure - Transmissions

I dont think so because you are missing numbers and the codes arent here, but heres the list for the 3 digits.




3 Digit codes

111





System checks OK

112


(O,M)


Intake Air Temperature (IAT) sensor is/was low or grounded - IAT

113


(O,M)


IAT sensor is/was high or open - IAT

114


(O,R)


IAT sensor out of range - IAT

116


(O,R)


Engine Coolant (ECT) sensor out of range - ECT

117


(O,M)


ECT sensor is/was low or grounded - ECT

118


(O,M)


ECT sensor is/was high or open - ECT

121


(O,R,M)


Throttle Position (TP) sensor out of range - TPS

122


(O,M)


TP low (possibly grounded or open circuit) - TPS

123


(O,M)


TP is/was high or short to power - TPS

124


(M)


TP voltage was higher than expected - Fuel control

125


(M)


TP voltage was lower than expected - Fuel control

126


(O,R,M)


MAP or BARO sensor out of range - ">MAP

128


(M)


MAP vacuum has not been changing - check vacuum lines - ">MAP

129


(R)


No MAP or Mass Air Flow sensor change during "goose" test - MAP MAF

136


(R)


Oxygen sensor not switching/system lean Left or Front HO2S - Fuel control

137


(R)


Oxygen sensor not switching/system rich Left or Front HO2S - Fuel control

138


(R)


Fault in Cold Start Injector circuit - Fuel control

139


(M)


Oxygen sensor not switching Left or Front HO2S - Fuel control

144


(M)


Oxygen sensor not switching Single, Right or Rear HO2S - Fuel control

157


(R,M)


Mass Air Flow signal is/was low or grounded - MAF

158


(O,R,M)


MAF sensor is/was high or short to power - MAF

159


(O,R)


MAF sensor is/was out of range - MAF

167


(R)


No Throttle Position sensor change in "goose" test (must get at least 25% rotation) - TPS

171


(M)


Oxygen sensor not switching - system was at adaptive limits - Single, Right or Rear HO2S - Fuel control

172


(R,M)


Oxygen sensor not switching - system is or was lean - Single, Right or Rear HO2S - Fuel control

173


(R,M)


Oxygen sensor not switching - system is or was rich - Single, Right or Rear HO2S - Fuel control

174


(M)


Oxygen sensor was slow in switching Single, Right or Rear HO2S - Fuel control

175


(M)


Oxygen sensor not switching - system was at adaptive limits - Left or Front HO2S - Fuel control

176


(M)


Oxygen sensor not switching - system is or was lean Left or Front HO2S - Fuel control

177


(M)


Oxygen sensor not switching - system was rich Left or Front HO2S - Fuel control

178


(M)


Oxygen sensor was slow in switching Left or Front HO2S - Fuel control

179


(M)


Fuel system was rich at part throttle Single, Right or Rear HO2S - Fuel control

181


(M)


Fuel system was lean at part throttle Single, Right or Rear HO2S - Fuel control

182


(M)


Fuel system was rich at idle Single, Right or Rear HO2S - Fuel control

183


(M)


Fuel system was lean at idle Single, Right or Rear HO2S - Fuel control

184


(M)


Mass Air (MAF) output higher than expected - Fuel control

185


(M)


Mass Air (MAF) output lower than expected - Fuel control

186


(M)


Injector pulse width longer than expected or Mass Air Flow (MAF) lower than expected - Fuel control

187





Injector pulse width shorter than expected or Mass Air Flow (MAF) higher than expected - Fuel control

188


(M)


Fuel system was rich at part throttle - Left or Front HO2S - Fuel control

189


(M)


Fuel system was lean at part throttle - Left or Front HO2S - Fuel control

191


(M)


Fuel system was rich at idle - Left or Front HO2S - Fuel control

192


(M)


Fuel system was lean at idle - Left or Front HO2S - Fuel control

193





Failure in Flexible Fuel (FF) sensor circuit - Fuel control

194


(M)


Perform cylinder balance test to check for inoperative injectors

195


(M)


Perform cylinder balance test to check for inoperative injectors

211


(M)


Ignition PIP signal was erratic or missing - Ignition Systems

212


(M)


Ignition TACH signal was erratic (module/wiring) or SPOUT circuit fault - Ignition Systems

213


(R)


Ignition SPOUT or SAW circuit open or shorted - Ignition Systems

214


(M)


Error in Cylinder ID (CID) circuit or signal - Ignition Systems

215


(M)


Primary circuit failure - ignition coil 1 - Ignition Systems

216


(M)


Primary circuit failure - ignition coil 2 - Ignition Systems

217


(M)


Primary circuit failure - ignition coil 3 - Ignition Systems

218


(M)


IDM signal open or high or left coil pack failure - Ignition Systems

219


(M)


SPOUT circuit failure, timing defaulted to 10 degrees - follow code 213 diagnosis

222


(M)


IDM open or high or right coil pack failure - Ignition Systems

223


(M)


Dual Plug (DPI), SPOUT or IDM circuit fault - Ignition Systems

224


(M)


Failure in ignition coil primary circuit - Ignition Systems

225


(R)


Knock sensor not tested (ignore if not pinging) - KS

226


(O)


Ignition Diagnostic Monitor (IDM) signal fault - Ignition Systems

232


(M)


EI primary coil circuit failure - Ignition Systems

238


(M)


EI primary circuit failure - ignition coil 4 - Ignition Systems

311


(R)


AIR system not working - Single, Right or Rear HO2S - Air Injection

312


(R)


AIR not diverting - Air Injection

313


(R)


AIR not bypassing - Air Injection

314


(R)


AIR inoperative, Left or Front HO2S - Air Injection

326


(R,M)


Pressure Feedback EGR shows low pressure EGR not seating or not seating intermittantly - PFE

327


(O,R,M)


EGR feedback signal is/was low - EVR or PFE

328


(O,R,M)


EGR Valve Position (EVP) is/was low - EVR

332


(R,M)


EGR did not open/respond during test or if memory code, did not open intermittantly - EVR or PFE

334


(O,R,M)


EVP sensor is/was high - EVR

335


(O)


EGR feedback signal is/was out of range - EVR or PFE

336


(O,R,M)


PFE sensor signal is/was was high - ">PFE

337


(O,R,M)


EGR feedback signal is/was was high - EVR

338


(M)


Cooling system did not heat up (check cooling system / thermostat operation)

339


(M)


Cooling system overheated (check cooling system / thermostat operation)

341


(O)


Octane jumper installed (information only code to notify you if it is installed)

411


(R)


Idle speed system not controlling idle properly (generally idle too high) - ISC

412


(R)


Idle speed system not controlling idle properly (generally idle too low) - ISC

452


(M)


Vehicle Speed Sensor (VSS) problem

511


(O)


No power to PCM pin 1 or bad PCM (processor)

512


(M)


Memory power (PCM pin 1) was interrupted - Was battery disconnected ?

513


(O)


Replace processor (PCM) (internal failure)

519


(O)


PSP switch/circuit open - PSP h Pedal Position (CPP) circuit fault - PNP

528


(M)


System shows voltage at pin 10 (is A/C on ?) or pin 30 (PNP, CPP switch) - PNP

529


(M)


Data Communications Link to processor failure Service any EEC codes, erase memory and retest If code is still present refer to instrument cluster diagnosis manual

533


(M)


Data Communications Link to instrument cluster failure - see 529

536


(O,R,M)


Brake On Off open or shorted to ground - BOO

538


(R)


System did not receive "goose" test - TESTS

539


(O)


System shows voltage at PCM pin 10 Is A/C on ?

542


(O,M)


Fuel pump open, bad ground or always on - - Power / Fuel Pump Circuits

543


(O)


Fuel pump monitor circuit shows no power - Power / Fuel Pump Circuits




(M)


(Service 556 code first if present) Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits

551





Problem in Intake Manifold Runner Control (IMRC) solenoid/circuit - Solenoids

552


(O)


AIRB solenoid/circuit failure - Solenoids

553


(O)


AIRD solenoid/circuit failure - Solenoids

554


(O)


Fuel Press Regulator Control solenoid/circuit fault - Power / Fuel Pump Circuits

556


(O,M)


Fuel pump relay primary circuit fault - Power / Fuel Pump Circuits

557


(O,M)


Low speed pump relay primary circuit fault - Power / Fuel Pump Circuits

558


(O)


EGR vacuum regulator solenoid/circuit failure - EVR or PFE or Solenoids

559


(O)


A/C relay primary circuit fault - A/C and Fan Circuits

563


(O)


High Fan Control (HFC) circuit failure - A/C and Fan Circuits

564


(O)


Fan Control (FC) circuit failure - A/C and Fan Circuits

565


(O)


Canister Purge 1 solenoid/circuit failure - Solenoids

566


(O)


transmission 3/4 shift solenoid/circuit - Transmissions

569


(O)


Canister Purge 2 solenoid/circuit failure - Solenoids

578


(M)


A/C pressure sensor VREF short to ground - A/C and Fan Circuits

579


(M)


ACP sensor did not change with A/C on - A/C and Fan Circuits

581


(M)


Cooling fan current was excessive - A/C and Fan Circuits

582


(O)


Open cooling fan circuit - A/C and Fan Circuits

583


(M)


Fuel pump current was excessive - Power / Fuel Pump Circuits

584


(M)


Open power ground circuit - Power / Fuel Pump Circuits

585


(M)


A/C clutch current was excessive - A/C and Fan Circuits

586


(M)


Open circuit in A/C clutch - A/C and Fan Circuits

587


(O, M)


Communication problem between PCM and Variable Control Relay Module (VCRM) - Power / Fuel Pump Circuits

617


(M)


Transmission shift failure (1/2 shift) - Transmissions

618


(M)


Transmission shift failure (2/3 shift) - Transmissions

619


(M)


Transmission shift failure (3/4 shift) - Transmissions

621


(O)


Solenoid/circuit failure - shift solenoid 1 - Transmissions

622


(O)


Solenoid/circuit failure - shift solenoid 2 - Transmissions

624


(O,M)


Solenoid/circuit failure -Electronic Pressure Control (EPC) current is high - Transmissions

625


(O,M)


Solenoid/circuit failure - Electronic Pressure Control (EPC) current is low - Transmissions

626


(O)


Transmission Coast Clutch (CCS) Solenoid/circuit fault - Transmissions

627


(O)


Torque Converter Clutch circuit fault - Transmissions

628


(M)


Excessive converter clutch slippage - Transmissions

629


(O,M)


Torque Converter Clutch circuit fault - Transmissions

631


(O)


Overdrive Cancel Light circuit problem - Transmissions

632


(R)


E4OD - Transmission Control Switch (TCS) should be cycled once between engine ID and Goose test

633


(O)


4x4L switch should be in 4x2 or 4x4 high for the test

634


(O,M)


Park/Neutral Position (PNP) or Clutch Pedal Position (CPP) circuit fault Electronic shift transmission - Manual Lever Position (MLP) sensor out of range in Park-Transmissions

636


(O,R)


Transmission Oil Temperature (TOT) sensor out of range - Transmissions

637


(O,M)


TOT sensor is/was high or open - Transmissions

638


(O,M)


TOT sensor is/was low or grounded - Transmissions

639


(R,M)


Transmission Speed sensor (TSS) circuit fault - Transmissions

641


(O)


Transmission solenoid/circuit failure Shift Solenoid 3 - Transmissions

643


(O,M)


Torque Converter Clutch (TCC) circuit - Transmissions

645


(M)


Transmission 1st gear failure - Transmissions

646


(M)


Transmission 2nd gear failure - Transmissions

647


(M)


Transmission 3rd gear failure - Transmissions

648


(M)


Transmission 4th gear failure - Transmissions

649


(M)


Transmission EPC system failure - Transmissions

651


(M)


Transmission EPC solenoid/circuit fault - Transmissions

652


(O)


Torque Converter Clutch (TCC) circuit fault - Transmissions

654


(O)


Transmission selector not in PARK - Transmissions

656


(M)


Torque Converter Clutch (TCC) slip - Transmissions

657


(M)


Transmission temperature was excessive - Transmissions





[an error occurred while processing this directive]

Code 12 -Idle Air Bypass motor not controlling idle properly (generally idle too low) - IAB dirty or not working. Take it off and clean it thoroughly with throttle body cleaner. Clean the electrical contacts with non flammable brake parts cleaner at the same time.

Code 23 - Throttle sensor out of range or throttle set too high - TPS needs to be reset to below 1.2 volts at idle. Keep in mind that when you turn the idle screw to set the idle speed, you change the TPS setting.
You'll need a Digital Voltmeter (DVM) to do the job.

Wire colors & functions:
Orange/white = 5 volt VREF from the computer
Dark Green/lt green = TPS output to computer
Black/white = Signal ground from computer

Always use the Dark Green/lt green & Black/white wires to set the TPS base voltage.

Do the test with the ignition switch in the Run position without the engine running.

Use the Orange/white & Black white wires to verify the TPS has the correct 5 volts source from the computer.

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .6.v-.9 v.

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

If setting the TPS doesn’t fix the problem, then you may have wiring problems.
With the power off, measure the resistance between the black/white wire and battery ground. You should see less than 2 ohms. Check the same black /white wire on the TPS and MAP/Baro sensor. More than 1 ohm there and the wire is probably broken in the harness between the engine and the computer. The 10 pin connectors pass the black/white wire back to the computer, and can cause problems.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

See http://fordfuelinjection.com/index.php?p=6 for more wiring help & 10 pin connector diagrams

Code 33 - Insufficient EGR flow detected.
Look for vacuum leaks, cracked vacuum lines, failed EGR vacuum regulator. Check to see if you have 10” of vacuum at the EGR vacuum connection coming from the intake manifold. Look for electrical signal at the vacuum regulator solenoid valves located on the rear of the passenger side wheel well. Using a test light across the electrical connector, it should flicker as the electrical signal flickers. Remember that the computer does not source any power, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.
Check for resistance between the brown/lt green wire on the EGR sensor and pin 27 on the computer: you should have less than 1.5 ohm.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif


EGR test procedure courtesy of cjones

to check the EGR valve:
bring the engine to normal temp.
connect a vacuum pump to the EGR Valve
apply 5in vacuum to the valve.
if engine stumbled or died then EGR Valve and passage(there is a passageway through the heads and intake) are good.
if engine did NOT stumble or die then either the EGR Valve is bad and/or the passage is blocked.
if engine stumbled, connect vacuum gauge to the hose coming off of the EGR Valve
snap throttle to 2500 RPM (remember snap the throttle don't hold it there).
did the vacuum gauge show about 2-5 in vacuum?

if not, check for manifold vacuum at the EGR vacuum valve.
if you have manifold vacuum then connect vacuum gauge to the EGR valve side of the vacuum valve and snap throttle to 2500 RPM.
should read about 2- 5 in vacuum

The operation of the EGR vacuum regulator can be checked by using a test light applied across the wiring connector. Jumper the computer into self test mode and turn the key on but do not start the engine. You will hear all the actuators (including the EVR vacuum regulator) cycle. Watch for the light to flicker: that means the computer has signaled the EGR vacuum regulator successfully.

Code 41 or 91 - O2 indicates system lean. Look for a vacuum leak or failing O2 sensor. Code 41 is a RH side
sensor, code 91 is the LH side sensor.

The computer sees a lean mixture signal coming from the O2 sensors and tries to compensate by adding more fuel. Many times the end result is an engine that runs pig rich and stinks of unburned fuel.

The following is a Quote from Charles O. Probst, Ford fuel Injection & Electronic Engine control:
"When the mixture is lean, the exhaust gas has oxygen, about the same amount as the ambient air. So the sensor will generate less than 400 Millivolts. Remember lean = less voltage.

When the mixture is rich, there's less oxygen in the exhaust than in the ambient air , so voltage is generated between the two sides of the tip. The voltage is greater than 600 millivolts. Remember rich = more voltage.

Here's a tip: the newer the sensor, the more the voltage changes, swinging from as low as 0.1 volt to as much as 0.9 volt. As an oxygen sensor ages, the voltage changes get smaller and slower - the voltage change lags behind the change in exhaust gas oxygen.

Because the oxygen sensor generates its own voltage, never apply voltage and never measure resistance of the sensor circuit. To measure voltage signals, use an analog voltmeter with a high input impedance, at least 10 megohms. Remember, a digital voltmeter will average a changing voltage." End Quote

Testing the O2 sensors
Measuring the O2 sensor voltage at the computer will give you a good idea of how well they are working. You'll have to pull the passenger side kick panel off to gain access to the computer connector. Remove the plastic wiring cover to get to the back side of the wiring. Use a safety pin or paper clip to probe the connections from the rear. The computer pins are 29 (LH O2 with a dark green/pink wire) and 43 (RH O2 with a dark blue/pink wire). Use the ground next to the computer to ground the voltmeter. The O2 sensor voltage should switch between .2-.9 volt at idle.

Note that all resistance tests must be done with power off. Measuring resistance with a circuit powered on will give false readings and possibly damage the meter. Do not attempt to measure the resistance of the O2 sensors, it may damage them.

Testing the O2 sensor wiring harness
Most of the common multimeters have a resistance scale. Be sure the O2 sensors are disconnected and measure the resistance from the O2 sensor body harness to the pins on the computer.

The O2 sensor ground (orange wire with a ring terminal on it) is in the wiring harness for the fuel injection wiring. I grounded mine to one of the intake manifold bolts

Replace the O2 sensors in pairs if replacement is indicated. If one is weak or bad, the other one probably isn't far behind.

If you get only code 41 and have changed the sensor, look for vacuum leaks. This is especially true if you are having idle problems. The small plastic tubing is very brittle after many years of the heating it receives. Replace the tubing and check the PVC and the hoses connected to it.
A secondary problem with only a code 41 is for cars with an intact smog pump and cats. If the tube on the back of the heads clogs up the driver’s side, all the air from the smog pump gets dumped into one side. This excess air upsets the O2 sensor calibration and can set a false code 41. The cure is to remove the crossover tube and thoroughly clean the insides to that there is no carbon blocking the free flow of air to both heads.


Codes 44 & 94 - AIR system inoperative - Air Injection. Check vacuum lines for leaks, & cracks. Disconnect the big hose from smog pump: with the engine running you should feel air output. Reconnect the smog pump hose & apply vacuum to the first vacuum controlled valve: Its purpose is to either dump the pump's output to the atmosphere or pass it to the next valve. The next vacuum controlled valve directs the air to either the cylinder heads when the engine is cold or to the catalytic converter when the engine is warm. Disconnect the big hoses from the back side of the vacuum controlled valve and start the engine. Apply vacuum to the valve and see if the airflow changes from one hose to the next.
The two electrical controlled vacuum valves mounted on the rear of the passenger side wheelwell turn the vacuum on & off under computer control. Check to see that both valves have +12 volts on the red wire. Then ground the white/red wire and the first solenoid should open and pass vacuum. Do the same thing to the light green/black wire on the second solenoid and it should open and pass vacuum.

Remember that the computer does not source power for any actuator or relay, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.

The computer provides the ground to complete the circuit to power the solenoid valve that turns the vacuum on or off. The computer is located under the passenger side kick panel. Remove the kick panel & the cover over the computer wiring connector pins. Check Pin 38 Solenoid valve #1 that provides vacuum to the first Thermactor control valve for a switch from 12-14 volts to 1 volt or less. Do the same with pin 32 solenoid valve #2 that provides vacuum to the second Thermactor control valve. Starting the engine with the computer jumpered to self test mode will cause all the actuators to toggle on and off. If after doing this and you see no switching of the voltage on and off, you can start testing the wiring for shorts to ground and broken wiring. An Ohm check to ground with the computer connector disconnected & the solenoid valves disconnected should show open circuit between the pin 32 and ground and again on pin 38 and ground. In like manner, there should be less than 1 ohm between pin 32 and solenoid valve #2 and pin 38 & Solenoid valve #1.

If after checking the resistance of the wiring & you are sure that there are no wiring faults, start looking at the solenoid valves. If you disconnect them, you can jumper power & ground to them to verify operation. Power & ground supplied should turn on the vacuum flow, remove either one and the vacuum should stop flowing.
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

See http://forums.stangnet.com/attachment.php?attachmentid=50636&d=1180923382 for a very nice drawing of the Thermactor Air System (smog pump) plumbing

If you have a catalytic converter H pipe, you need to fix these codes. If you don't, then don't worry about them