Need Help With New Motor

Discussion in 'Fox 5.0 Mustang Tech' started by skiwesser11, Aug 5, 2014.

  1. skiwesser11

    skiwesser11 Member

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    Ok, have 306, AFR 165's (58cc), edel rpm2 intake, Ed Curtis cam (.588- 119/121 @.050) pro M 80mm, 24# inj.

    Car stumbles like there's a really bad miss, won't idle or run at part or wot, you can keep it running but that's about it. Thought it was a bad injector, nope. Loose ground, checked all wiring. Thought maybe ECU fried, got a friends a9p to try, same as my a9l (it is a 5 speed)
    Would say it's some connection or loose wire or ground except, I stuck old speed density CPU in between trying the a9p and it'll run 2000% better, I can drive it, smokes white at idle and stumbles at part throttle but much better than either mass air ECU.
    We can't figure it out, could it take that long for a9l to "learn"? Sometimes it'll run well for a few seconds then back to sounding like it's got 2 plug wires off.
    We have checked everything we can think of, any ideas???
     
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  2. skiwesser11

    skiwesser11 Member

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    New info: unplugged maf with a9p in and it ran best so far, drove it 3-4 miles. Plug maf back in, back to stumble bumble tilt??!!??

    F press at 39-40, base timing 10*
     
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  3. skiwesser11

    skiwesser11 Member

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    Also, pulling codes tomorrow. Didn't have a working scanner
     
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  4. Dan_Soprano

    Dan_Soprano Mustang Master

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    Was this on initial startup after build or just happened out of nowhere?
     
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  5. jrichker

    jrichker StangNet's favorite TOOL
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    Did you move the wires in the computer wiring connector when you did the Mass Air conversion?
    If not, you missed an important step.
    See http://www.hotrod.com/pitstop/hrdp_0705_pitstop_ford_thunderbird_mass_air_sensor/photo_01.htm

    If so, you may have misplaced a wire.
    [​IMG]



    You don't need a scanner to dump codes, all you need is a paper clip...

    Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

    Dumping the computer diagnostic codes on 86-95 Mustangs

    Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

    Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

    Here's the way 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. You watch the flashing test lamp or Check Engine Light and count the flashes.

    Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

    Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
    Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

    [​IMG]

    [​IMG]

    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.

    [​IMG]

    The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

    89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

    [​IMG]

    The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


    WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

    What to expect:
    You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

    Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

    Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

    Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

    Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
    See AutoZone Part Number: 25886 , $10
    [​IMG]



    Alternate methods:
    For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

    Or for a nicer scanner see www.midwayautosupply.com/Equus-Digital-Ford-Code-Reader/dp/B000EW0KHW Equus - Digital Ford Code Reader (3145It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.
     
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    Last edited: Aug 5, 2014
  6. elarm1

    elarm1 Active Member

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    My money is on having the distributor stabbed in wrong.... so easy to do and often overlooked. Check tdc and timing
     
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  7. skiwesser11

    skiwesser11 Member

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    Put a stock meter on and it runs fine, with stock or electronics off of Pro M 80mm. Before I tried this it was throwing up several codes, f pump secondary circuit failure, ECT out of range,tps out of range, ect...
    I'm going to clear and scan again.
     
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  8. jrichker

    jrichker StangNet's favorite TOOL
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    Be sure to post the numerical values of the codes and I will post 5.0 Mustang specific definitions and fixes.
     
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  9. skiwesser11

    skiwesser11 Member

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    I will thank you. I'm going to clear the computer and scan it again.
     
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  10. skiwesser11

    skiwesser11 Member

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    Somehow we got dist in correctly the first time, we have had it 180* out but it wouldn't even start. But that is the first thing we checked. Ran decent at first startup then got progressively worse,.... quickly.
    Hopefully I can get it to accept the pro m 80mm housing as I sold the C&L..wish I didn't now so I could at least try it, the stock one is tiny, what is it 58mm?
     
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  11. skiwesser11

    skiwesser11 Member

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    Codes are:
    81 o
    82 o
    84 o
    95 o
    95 c
    33 c
    33 r
    41 c
    41 r

    Thanks
     
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  12. Dan_Soprano

    Dan_Soprano Mustang Master

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    I was going to say maybe the cam was degreed incorrectly, but if it ran fine at first.....
     
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  13. skiwesser11

    skiwesser11 Member

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    Runs great without 80mm housing of the pro m. I'm hoping ECU will adapt? I'm going to give it a few days to "learn" new setup, I'm thinking I may have to get my SCT chip re flashed (I removed it before startup of course as it was "burned" for old combo. Although the guy who loaned me the stock maf housing told me the chips are old school and tuner will reflash the the ECU itself through the serv port? I thought that wasn't possible on EEC IV?
     
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    Last edited: Aug 6, 2014
  14. FoxMustangLvr

    FoxMustangLvr Mustang Master

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    Is your car tuned to run without a MAF? If not, is your ProM 80mm MAF calibrated for your 24# injectors?
     
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  15. skiwesser11

    skiwesser11 Member

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    Not tuned for speed density, it is calibrated for 24# inj
     
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  16. FoxMustangLvr

    FoxMustangLvr Mustang Master

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    I didn't mean SD, some programmers/tunes setup up your engine to eliminate the need for a MAF sensor completely. How do you know it's calibrated for 24's, did you buy it brand new or told so? Typically when you unplug a MAF sensor your car runs like crap, not the other way around. Is this car new to you? Did you just rebuild the motor yourself or did you buy the engine already setup this way? A little more car history will help us with the problem solving.
     
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  17. skiwesser11

    skiwesser11 Member

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    Ok, it the chip was tuned with C&L 73mm, different cam, intake.. So I took chip out of a9l, right now I still have an a9p processor in it.

    Since rebuild pro m 80 bought new, rpm2 new, aforementioned cam. I have owned the car since new, blew head gasket on last rebuild and decided to go bigger cam and better intake and maf. Everything but machine work done by myself and my brother (he's a honda mechanic) The pro m I'm positive is for 24's (again I just bought it). However the stock one I'm currently running is for 19's regardless of which electronics I'm using, correct? Regardless it runs decent with it, I still haven't tried the pro m again yet, but it has started, ran fine since switch to stock housing.
    Crane hi 6 ignition box doesn't work since rebuild either but we moved it so I think (hope) it's a loose ground or something.
    Thank you
     
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    Last edited: Aug 7, 2014
  18. jrichker

    jrichker StangNet's favorite TOOL
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    All but one of the codes are emissions related.
    Removing the pollution control equipment from a 5.0 Mustang is a bad idea. All you have accomplished is to make the computer mad and spit codes. The pollution control equipment all shuts off at wide open throttle, so the HP losses from it on the car are 2-5 HP. The catalytic converters may soak a few more HP than that. None of the pollution control equipment reduces the HP enough to cost you a race in anything but professional drag strip competition. I seriously doubt that you will be in the final runoff on “Pinks”, so leave the smog equipment in place and make sure it is working correctly.

    Know what does what before removing it. Remove or disable the wrong thing and the computer sets the check engine light and runs in "limp mode". Limp mode means reduced power and fuel economy.

    If you removed the smog pump and still have catalytic converters, they will ultimately clog and fail.

    Here's a book that will get you started with how the Ford electronic engine control or "computer" works.

    Ford Fuel Injection & Electronic Engine Control 1988-1993 by James Probst :ISBN 0-8376-0301-3.

    It's about $20-$45 from Borders.com see http://www.amazon.com/ . Select books and then select search. Use the ISBN number (without dashes or spaces) to do a search

    Use the ISBN number and your local library can get you a loaner copy for free. Only thing is you are limited to keeping the book for two weeks. It is very good, and I found it to be very helpful.

    Remove any of the equipment and you will not pass a full smog check, cannot title the car in an area that does smog checks and have broken several federal laws. Granted that the Feds are short on people to check cars, but it is still Federal law.

    "Why should I leave the smog equipment on if I live in an area that doesn't do smog inspections?"
    What's good sauce for the goose is good sauce for the gander. I lived in Florida and had two smog pumps fail on two different 89 5.0 Mustangs. I replaced both of them, even though there was no emissions inspection. Why?

    1.) It a federal law that requires emissions equipment to be in place and functional. I have no intention of breaking a law designed to protect my general health and wellbeing, even if I don't like it. I have respect for the rights and wellbeing of other people, and am not one of those whose nature is rebellion.

    2.) Whatever imaginary "improvements" someone may strive for, there is very little evidence that the results of removing emissions results in a better car. I can achieve excellent results in performance with all the smog equipment in place and working properly. Maybe you can't, but that is no excuse for removing the emissions equipment. Look at the new 5.0 Mustangs – 281 cubic inches and 400+ flywheel HP with full emissions equipment with no aftermarket parts. That tells me that it is possible on a mass production car. It also shows that the guys that designed the engine knew what they were doing to achieve that goal.

    3.) I like to breathe clean air, and working emissions equipment helps me do my part to make that possible. Los Angeles has breathable air even with millions of cars: Beijing, the capitol of China has some of the worst air in the world. Why – no emissions requirements for cars.

    I don’t want to live where the air looks like this…
    [​IMG]
    See http://www.taipeitimes.com/News/feat/archives/2014/01/15/2003581312



    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 changes. 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.

    Backside view of the computer wiring connector:
    [​IMG]

    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 or see the EGR test jig drawing below. Connnect the test jig or to directly to manifold vacuum.

    Do not connect the EGR test jig to the EVR (Electronic Vacuum Regulator).


    apply 5in vacuum to the valve. Using the test jig, use your finger to vary the vacuum

    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 EGR test jig to the hose coming off of the EGR Valve.
    Use your finger to cap the open port on the vacuum tee.
    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 the EVR has failed

    EGR test jig
    [​IMG]

    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. Or 43 Three digit code 172 or 176 - O2 sensor indicates system lean. Look for a vacuum leak or failing O2 sensor.

    Revised 20-Jan-2014 to add code 43 to test collection

    Code 41 is a RH side sensor, as viewed from the driver's seat.
    Code 91 is the LH side sensor, as viewed from the driver's seat.

    Code 172 is the RH side sensor, as viewed from the driver's seat.
    Code 176 is the LH side sensor, as viewed from the driver's seat.

    Code 43 is not side specific according to the Probst Ford Fuel injection book.

    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 87-93 5.0 Mustangs
    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.

    Disconnect the O2 sensor from the harness and use the body side O2 sensor harness as the starting point for testing. Do not measure the resistance of the O2 sensor , you may damage it. Resistance measurements for the O2 sensor harness are made with one meter lead on the O2 sensor harness and the other meter lead on the computer wire or pin for the O2 sensor.

    Backside view of the computer wiring connector:
    [​IMG]

    87-90 5.0 Mustangs:
    Computer pin 43 Dark blue/Lt green – LH O2 sensor
    Computer pin 29 Dark Green/Pink – RH O2 sensor
    The computer pins are 29 (L\RH O2 with a dark green/pink wire) and 43 (LH 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.

    91-93 5.0 Mustangs:
    Computer pin 43 Red/Black – LH O2 sensor
    Computer pin 29 Gray/Lt blue – RH O2 sensor
    The computer pins are 29 (LH O2 with a Gray/Lt blue wire) and 43 (RH O2 with a Red/Black wire). Use the ground next to the computer to ground the voltmeter. The O2 sensor voltage should switch between .2-.9 volt at idle.


    Testing the O2 sensors 94-95 5.0 Mustangs
    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 red/black wire) and 27 (RH O2 with a gray/lt blue wire). Use pin 32 (gray/red wire) 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. Using the Low Ohms range (usually 200 Ohms) you should see less than 1.5 Ohms.

    87-90 5.0 Mustangs:
    Computer pin 43 Dark blue/Lt green – LH O2 sensor
    Computer pin 29 Dark Green/Pink – RH O2 sensor
    Disconnect the connector from the O2 sensor and measure the resistance:
    From the Dark blue/Lt green wire in the LH O2 sensor harness and the Dark blue/Lt green wire on the computer pin 43
    From the Dark Green/Pink wire on the RH Os sensor harness and the Dark Green/Pink wire on the computer pin 29

    91-93 5.0 Mustangs:
    Computer pin 43 Red/Black – LH O2 sensor
    Computer pin 29 Gray/Lt blue – RH O2 sensor
    Disconnect the connector from the O2 sensor and measure the resistance:
    From the Red/Black wire in the LH O2 sensor harness and the Red/Black wire on the computer pin 43
    From the Dark Green/Pink Gray/Lt blue wire on the RH Os sensor harness and the Gray/Lt blue wire on the computer pin 29

    94-95 5.0 Mustangs:
    Computer pin 29 Red/Black – LH O2 sensor
    Computer pin 27 Gray/Lt blue – RH O2 sensor
    From the Red/Black wire in the LH O2 sensor harness and the Red/Black wire on the computer pin 29
    From the Dark Green/Pink Gray/Lt blue wire on the RH Os sensor harness and the Gray/Lt blue wire on the computer pin 27

    There is a connector between the body harness and the O2 sensor harness. Make sure the connectors are mated together, the contacts and wiring are not damaged and the contacts are clean and not coated with oil.

    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

    Make sure you have the proper 3 wire O2 sensors. Only the 4 cylinder cars used a 4 wire sensor, which is not compatible with the V8 wiring harness.

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

    Code 41 can also be due to carbon plugging the driver’s side Thermactor air crossover tube on the back of the engine. The tube fills up with carbon and does not pass air to the driver’s side head ports, Remove the tube and clean it out so that both sides get good airflow: this may be more difficult than it sounds. You need something like a mini rotor-rooter to do the job because of the curves in the tube. Something like the outer spiral jacket of a flexible push-pull cable may be the thing that does the trick.

    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.




    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.

    Both 81 & 82 codes usually mean that some uneducated person removed the solenoid control valves for the Thermactor Air system in an attempt to make the car faster. It doesn't work that way: no working control valves can cause the cat converters to choke and clog. If you do not have cat converters on the car, you can ignore the 81 & 82 codes.


    Code 84 EGR Vacuum Regulator failure – Broken vacuum lines, no +12 volts, regulator coil open circuit, missing EGR vacuum regulator. 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 95 Key On, Engine not Running - the following test path is for 86-90 model Mustangs.

    The 95 code is because at one time or another, the fuel pump relay hiccupped and didn't provide power the pump when the computer told it to run. Sometimes this is a one time thing, other times it is a no run or runs poorly condition.

    [​IMG]

    Using the diagram, check the red/black wire from the fuel pump relay: you should see 12 volts or so. If not, check the inertia switch: on a hatch it is on the driver’s side by the taillight. Look for a black rubber plug that pops out: if you don't find it, then loosen up the plastic trim. Check for voltage on both sides of the switch. If there is voltage on both sides, then check the Pink/black wire on the fuel pump relay: it is the power feed to the fuel pump. No voltage there, check the Orange/Lt blue wire, it is the power feed to the fuel pump relay & has a fuse link in it. If there is good voltage there & at the Pink/black wire, swap the relay.

    Some Mass Air conversions neglect to run the extra fuel pump wire, and they always have a 95 code. See http://www.stangnet.com/tech/maf/massairconversion.html for more information on the Mass Air wiring conversion.

    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/ Everyone should bookmark this site.

    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

    Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
    http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

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

    HVAC vacuum diagram
    http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

    TFI module differences & pinout
    http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

    Fuse box layout
    http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif
     
    #18
  19. skiwesser11

    skiwesser11 Member

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    Only thing done recently was removing valves/solenoids from pass strut tower in an attempt to clean up the wiring. I agree I should have maintained the equipment but the pump locked up 20 yrs ago, before the internet or any personal experience/knowledge removed it and have since removed cats and blocked off passages in heads ect...
     
    #19

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