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What ive done so far with Codes

  • Thread starter Thread starter YoungGun
  • Start date Start date Mar 30, 2004
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YoungGun

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#1
  • Mar 30, 2004
  • #1
Ok heres what ive got/done so far.
I dumped some codes:

22 (With engine off) It says MAP Sensor, BARO on the codes. What I did was replace the Sensor. ( I Used a MAP sensor cause I was told on here they are the same)
12 Idle Speed Control or Air Bypass ( I have done nothing with this as of now cause I dunno what to do)

and with the engine running I got a 99

Now after I replaced the sensor I dumped the codes again and got the SAME codes.
Do I have to erase the codes in order for it to know the sensor has been changed? Or does the code go away?

After reading can anyone tell me where to go next? This started with my car running rich (You could pass out standing behind it) And I was told to dump the codes to see what was wrong and well here you have it.

12 (Engine off)
22 (Engine Off)
99 (Engine running)
 

Mike86Stang

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Apr 11, 2000
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Mar 30, 2004
#2
  • Mar 30, 2004
  • #2
I check the over the codes tonight but disconnect the bat for 15 mins so the EEC will reset. Run it a few times & pull it again.
 
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YoungGun

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#3
  • Mar 30, 2004
  • #3
Ok cool
Batt is now disconected. Should I run both diagnostics?
Engine on and Engine off?
 

Mike86Stang

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#4
  • Mar 30, 2004
  • #4
No need to really. The first set of codes you get are codes indicating what wrong right there & then. After the seperator code & you get the second set of codes, that's the hard codes or memory codes which have came up more than once over the last however many starting cycles.

So wether the engines running or not should make little to no diffrence. If you wanna "be sure" just do it. Worth the extra 5 min's to make sure there are no other problems.
 

siege

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Feb 23, 2003
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Mar 30, 2004
#5
  • Mar 30, 2004
  • #5
I think I read somewhere that if you disconnect the connections you make during the testing (while you're still testing) it will clear the codes...that might help if it doesn't reset...
 
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YoungGun

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#6
  • Mar 30, 2004
  • #6
Ok why would a 22 come up after I changed the Sensor the 22 is there for?
Im also curious about the 99 I got when I ran the engine on test
 
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YoungGun

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#7
  • Mar 30, 2004
  • #7
Just did the test again and got the same codes
22 and 12
and then 99 on the engine on run
 
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noslow5_0

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Nov 7, 2003
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Mar 30, 2004
#8
  • Mar 30, 2004
  • #8
well the 99 is either the system hasnt learned idle, or perform the goose test again... i always get that one, and dont know why... maybe someone can answer that for us???
 

jrichker

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#9
  • Mar 31, 2004
  • #9
Codes 12 & 99 are idle speed problems. The computer hasn't been able to control the idle using the IAB. Likely problem sources are:
1.) Mechanical problems such as binding throttle butterfly, or idle screw set too low.
2.) Vacuum leaks - use a vacuum gauge, you should have 16"-19" of vacuum at idle. Check hoses, connections, gaskets & seals for leaks and condition.
3.) Bad connections or broken wiring on the IAB circuit. Clean with electrical contact cleaner and scrape contacts bright & shiny.
4.) Bad IAB - replace IAB

Code 22 MAP failure:
1.) Possible bad sensor (even though you replaced it).
2.) Bad wiring. Look for +5 volts on the Orange/white wire. With the engine off, measure resistance between ground and the Black/white wire - you should see less than 1 ohm. Remove the wiring cover from the computer connector. Use a safety pin or paper clip to back probe pin 45. Set your voltmeter on ac, you should see 4-5 volts AC. If you have access to a frequency counter or oscilloscope, you can measure the output to be sure the 154 HZ square wave is present.

Fix the MAP problem first and the code 12 & 99 may go away.

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
 

Mike86Stang

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#10
  • Mar 31, 2004
  • #10
Yeah basically from what I looked up on it it's all idle control issues.
I say clean the TB & IAC motor, reset your idle speed & tps set it at 800 rpm or so.

As far as what jrichker said is true, solveing the BAP/MAP issue may solve the other issues. I read that the middle wire should read about 2.5v one should be ground & the other should be the 5v v-ref signal.

Check the wires on the MAP/BAP & let us know.

Mike
 
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YoungGun

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#11
  • Mar 31, 2004
  • #11
edit
see below
 
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YoungGun

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#12
  • Mar 31, 2004
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Ok this is what I got

Orange/ White wire - Seems to be dead. I get nothing from it
Black/white - at about 5 ohms with engine off
Pin 45 - 9ACV

How I tested the wires was I put a Pin in the female end and used my volt meter. I dunno if that matters just wanted to throw that out there

Once again Im getting no reading from the orange/white wire
 

Mike86Stang

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#13
  • Mar 31, 2004
  • #13
9v!?! Hmm shouldn't be seeing that much voltage. I'm thinking possible EEC issue possibly
.
Have you checked the corrresponding PIN on the EEC harness (by the computer) to see if it's got a signal (middle wire should be at 2.5v). That'll tell you if it's wiring or the possible the EEC. Double & triple check all wires before replacing the EEC.
 

jrichker

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  • Mar 31, 2004
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YoungGun said:
Ok this is what I got

Orange/ White wire - Seems to be dead. I get nothing from it
Black/white - at about 5 ohms with engine off
Pin 45 - 9ACV

How I tested the wires was I put a Pin in the female end and used my volt meter. I dunno if that matters just wanted to throw that out there

Once again Im getting no reading from the orange/white wire
Click to expand...

Pull the connector off the sensor and stick the probe or a paper clip into the socket. that will enable you the check the orange/white wire for voltage and the black/white wire for resistance.

The black/white wire is the ground wire for several sensors, and is very important. It should read less than 1 ohm resistance between it and the chassis ground. be sure you have the ignition switch OFF when you make the check or your readings will be wrong.

Turn the ignition switch ON to do the rest of the checks.

If you get no voltage from the orange/white wire, check the same wire on the TPS. If you have +5 volts there, you have a broken wire in the harness.

No voltage at the TPS, check the orange/white wire on the EGR sensor. No voltage there, and either the computer has died or there is a break in the wiring between the main harness and the computer.

Turn the ignition switch OFF and you can use the Ohmmeter to measure the resistance between connectors on the orange/white wire. You should see no more than 1 ohm between the orange/white wire on the MAP sensor, TPS and EGR sensors.
 
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YoungGun

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#15
  • Mar 31, 2004
  • #15
Worse case scenerio what am I looking to spend in repairs?
 
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YoungGun

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#16
  • Mar 31, 2004
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Ok No readings at the TP....Wire is dead
Now where is the EGR Sensor?
Anyone?
 
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YoungGun

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#17
  • Mar 31, 2004
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Ok I found the EGR Sensor
When I read the volts it was off the table on the 10V setting and when I switched it to the 250 setting I got no reading. Im at a loss
 
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YoungGun

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#18
  • Mar 31, 2004
  • #18
Upon further investigation
I have found that the wires seen to be mixed up?
Matching it up with this diagram here:
http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

The white/Orange wire is where the Black/white should be
and vice versa
The green is in the correct spot


Any input from experienced guys?
 
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YoungGun

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#19
  • Mar 31, 2004
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I doubt the wires seeming mixed up has anything to do with it. I had the codes read about a year ago and I got No Defects. Im sure if the wire was backwards it woulda pinged back then
 
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YoungGun

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#20
  • Apr 1, 2004
  • #20
ttt
 
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