New car No power

Is it missing again or just lost power?

I would start with the basics. Do a cylinder balance test and see if all eight cyliders are contributing. you can do this by pulling each spark plug and measuring the drop in rpms an each cylinder. If you get to one that does not have any drop then that is the suspect cylinder.

turp23 said:

In less than ten minutes, 2 replies. That is awesome.

The best way for me to explain would be as such:

When you accelerate and start shifting you feel it in almost every gear. Strong hesitation. No matter how hard I mash on the gas, the engine starts hesitating and it is very distinct. If you drive in any gear with a steady rpm, you can feel a dead miss. What sucks is sometimes you will actually feel the motor randomly wake up and it will smooth out an add some extra power. Do I sound like I am crazy?

Here are the key on engine off codes: 67 81 82 85 84 Memory: 33 63 91
I can not pull any engine on codes, and my engine light does work. To do the cylinder balance test, what is the safest method to use without getting bit? Stupid question, please dont remind me. To add more disturbance. there is an injector that has bad written on it in sharpie, alarming?

Click to expand...

Insulated spark plug boot pliers work the best. But you could insulate a set by wrapping them with electrical tape.

See the code 67 test path to find out why you can't pull engine running codes.

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 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 63 - Throttle Position Sensor (TPS) signal too low TPS . TPS out of adjustment, or 5 V VREF missing, broken wiring or bad connections.

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.

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

Setting the TPS: you'll need a good Digital Voltmeter (DVM) to do the job. Set the TPS voltage at .5- 1.1 range. Because of the variables involved with the tolerances of both computer and DVM, I would shoot for somewhere between .6 and 1.0 volts. Unless you have a Fluke or other high grade DVM, the second digit past the decimal point on cheap DVM’s is probably fantasy. Since the computer zeros out the TPS voltage every time it powers up, playing with the settings isn't an effective aid to performance or drivability. The main purpose of checking the TPS is to make sure it isn't way out of range and causing problems.

The Orange/White wire is the VREF 5 volts from the computer. You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS. Use a pair of safety pins to probe the TPS connector from the rear of the connector. You may find it a little difficult to make a good connection, but keep trying. Put the safety pins in the Dark Green/Lt green wire and Black/White wire. Make sure the ignition switch is in the Run position but the engine isn't running.

Here’s a TPS tip I got from NoGo50

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.

(copied from MustangMax, Glendale AZ)

A.) 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.

B.) 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.

C.) Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

D.) The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.

Code 67 - clutch not depressed (5 speed) or car not in neutral or park (auto) or A/C in On position when codes where dumped. Possible neutral safety switch or wiring problem. This code may prevent you from running the Key On Engine On tests. You can generally ignore this code, since it has no effect on engine performance.

The computer wants to make sure the A/C is off due to the added load on the engine for the engine running tests. It also checks to see that the transmission is in Neutral and the clutch depressed (T5, T56, Tremec 3550 & TKO)). This prevents the car from being driven while the computer is in test mode. Key On Engine Running test mode takes the throttle control away from the driver for several tests. This could prove hazardous if the computer was jumpered into test mode and then driven.

The NSS code 67 can be bypassed for testing. You will need to temporarily ground pin 30 to the chassis.

Code 41 or 91 - O2 indicates system lean. Look for a vacuum leak or failing O2 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.

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.

The remainder of the codes are due to some uneducated person removing the smog gear. This accomplishes nothing to improve the performance of the car.

Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The solenoid valve located on the back side of the passenger side wheel well is not functional. Possible bad wiring, bad connections, missing or defective solenoid valve. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.

With the with the ignition on, look for 12 volts on the red wire on the solenoid connector. No 12 volts and you have wiring problems.

With the engine running, stick a safety pin in the LT Green/Black wire for the solenoid valve & ground it. That should turn the solenoid on and cause air to flow out the port that goes to the pipe connected to the cats. If it doesn't, the valve is bad. If it does cause the airflow to switch, the computer or wiring going to the computer is not signaling the solenoid valve to open.

Putting the computer into self test mode will cause the solenoid valve to toggle. If you listen carefully, you may hear it change states.

Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. Possible bad wiring, bad connections, missing or defective solenoid valve. Check the solenoid valve for +12 volts at the Red wire and look for the Red/White wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the Red/White wire for the solenoid valve

With the engine running, stick a safety pin in the Red/White wire for the solenoid valve & ground it. That should turn the solenoid on and cause air to flow out the port that goes to the pipe connected to the heads. If it doesn't, the valve is bad. If it does cause the airflow to switch, the computer or wiring going to the computer is not signaling the solenoid valve to open.

Code 84 EGR Vacuum Regulator failure – Broken vacuum lines, no +12 volts, regulator coil open circuit. The EVR regulates vacuum to the EGR valve to maintain the correct amount of vacuum. The solenoid coil should measure 20-70 Ohms resistance. The regulator has a vacuum feed on the bottom which draws from the intake manifold. The other vacuum line is regulated vacuum going to the EGR valve. One side of the EVR electrical circuit is +12 volts anytime the ignition switch is in the run position. The other side of the electrical circuit is the ground path and is controlled by the computer. The computer switches the ground on and off to control the regulator solenoid.

Code 85 - CANP solenoid - The Carbon Canister solenoid is inoperative. Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by grounding the gray/yellow wire to the solenoid and blowing through it.
The computer provides the ground for the solenoid. The red wire to the solenoid is always energized any time the ignition switch is in the run position.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel.

It does not weigh but a pound or so and helps richen up the cruse mixture. It draws no HP & keeps the car from smelling like gasoline in a closed garage. So with all these good things and no bad ones, why not hook it up & use it?

Don't pull spark plug wires off to do a cylinder balance test. The computer will do it for you.

Cylinder balance test:
Warm the car's engine up to normal operating temperature. Use a
jumper wire or paper clip to put the computer into test mode. Start
the engine and let it go through the normal diagnostic tests, then
quickly press the throttle to the floor. The engine RPM should exceed
2500 RPM's for a brief second. The engine RPM's will increase to about
1450-1600 RPM and hold steady. The engine will shut off power to each
injector, one at a time. When it has sequenced through all 8 injectors,
it will flash 9 for everything OK, or the number of the failing cylinder
such as 2 for cylinder #2. Quickly pressing the throttle again up to
2500 RPM’s will cause the test to re-run with smaller qualifying figures.
Do it a third time, and if the same cylinder shows up, the cylinder is
weak and isn’t putting out power like it should. See the Chilton’s Shop
manual for the complete test procedure

Here's the link to dump the computer codes with only a jumper wire
or paper clip and the check engine light, or test light or voltmeter.
I’ve used it for years, and it works great.



See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

For those who are intimidated by all the wires & connections,
see http://www.actron.com/product_detail.php?pid=16153 for what a
typical hand scanner looks like. Normal retail price is about $30 or so
at Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes
or beeps.. Cost is $33.

Do a compression test on all the cylinders.
Take special note of any cylinder that shows up as weak in the cylinder
balance test. Low compression on one of these cylinders rules out the
injectors as being the most likely cause of the problem. Look at cylinders
that fail the cylinder balance test but have good compression. These
cylinders either have a bad injector, bad spark plug or spark plug wire.
Move the wire and then the spark plug to another cylinder and run the
cylinder balance test again. If it follows the moved wire or spark plug,
you have found the problem. If the same cylinder fails the test again,
the injector is bad. If different cylinders fail the cylinder balance test,
you have ignition problems or wiring problems in the 10 pin black &
white electrical connectors located by the EGR.

How to do a compression test:
Only use a compression tester with a screw in adapter for the spark
plug hole. The other type leaks too much to get an accurate reading.
Your local auto parts store may have a compression tester to rent.
If you do mechanic work on your own car on a regular basis, it would
be a good tool to add to your collection.

With the engine warmed up, remove all spark plugs and prop the
throttle wide open, crank the engine until it the gage reading stops
increasing. On a cold engine, it will be hard to tell what's good &
what's not. Some of the recent posts have numbers ranging from
140-170 psi. If the compression is low, squirt some oil in the cylinder
and do it again – if it comes up, the rings are worn. There should be
no more than 10% difference between cylinders. Use a blow down
leak test (puts compressed air inside cylinders) on cylinders that
have more than 10% difference.

See the link to my site for details on how to build your own blow
down type compression tester.

Code 21 – ECT sensor out of range. Broken or damaged wiring, bad ECT sensor.
Note that that if the outside air temp is below 50 degrees F that the test for the
ECT can be in error.

The ECT sensor has absolutely nothing to do with the temperature gauge. They are
different animals. The ECT sensor is normally located it the RH front of the engine in
the water feed tubes for the heater.

The ACT & ECT have the same thermistor, so the table values are the same

ACT & ECT test data:

Use Pin 46 on the computer for ground for both ECT & ACT to get most accurate
readings.

Pin 7 on the computer - ECT signal in. at 176 degrees F it should be .80 volts

Pin 25 on the computer - ACT signal in. at 50 degrees F it should be 3.5 volts. It is
a good number if the ACT is mounted in the inlet airbox. If it is mounted in the lower
intake manifold, the voltage readings will be lower because of the heat transfer.

Voltages may be measured across the ECT/ACT by probing the connector from
the rear. A pair of safety pins may be helpful in doing this. Use care in doing it
so that you don't damage the wiring or connector.

Here's the table :

50 degrees F = 3.52 v
68 degrees F = 3.02 v
86 degrees F = 2.62 v
104 degrees F = 2.16 v
122 degrees F = 1.72 v
140 degrees F = 1.35 v
158 degrees F = 1.04 v
176 degrees F = .80 v
194 degrees F = .61
212 degrees F = .47 v
230 degrees F = .36 v
248 degrees F = .28 v

Ohms measures at the computer with the computer disconnected, or at
the sensor with the sensor disconnected.

50 degrees F = 58.75 K ohms
68 degrees F = 37.30 K ohms
86 degrees F = 27.27 K ohms
104 degrees F = 16.15 K ohms
122 degrees F = 10.97 K ohms
140 degrees F = 7.60 K ohms
158 degrees F = 5.37 K ohms
176 degrees F = 3.84 K ohms
194 degrees F = 2.80 K ohms
212 degrees F = 2.07 K ohms
230 degrees F = 1.55 K ohms
248 degrees F = 1.18 k ohms

Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer)
& Stang&2Birds
(website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

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 1 ohm. 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 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 42 & 92 (engine running) System rich - Fuel control or (memory) System was rich for
15 seconds or more (no HO2S switching) - Fuel control. Look for leaking injectors, fuel pressure
too high, cylinder(s) not firing due to bad ignition.
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.

turp23 said:

I am not clear on how to apply 5in of vaccum to the egr valve. How would I do this? Secondly,
whether some of you find it silly or not, I am not so good with a dvm. Of course it could be a cheap dvm and that why its
giving me problems, but I will try with a different meter. And thirdly, to measure the voltage on the o2 sensors, do I do
this with the engine running?

Click to expand...

Vacuum: use one of the MityVac testers:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=39522

Or use a vacuum gauge and with a tee fitting. Connect one end of the tee to any vacuum port on the intake manifold.
Connect the other end of the tee to the EGR valve. Connect one end ot the tee to the vacuum gauge. Kink the line
connected to the intake manifold so no vacuum will pass. Start the engine and slowly release tension on the kink or
bend until you see 2"-5" vacuum on the gauge.

Since the O2 sensors do not generate a voltage without a flow of hot exhaust gases, the engine must be running to do the test.