Run Problem

General karthief · May 11, 2017

Ok first I am going to say I think some of the problems you are having stems from using a crown vic efi harness, I maybe wrong but those where non ho engines and the sd computer will be for ho, thus different firing orders, while this may not be a problem in itself it may be an issue with pin location. I will post a link to an old thread that may help, you have peaked my intrest in this because I'm thinking of an efi swap in a vintage body but I will be using a harness from a 91 stang. I already have the harness plus a spare one and related computer, look over the thread I linked and see if it will help you determine what problems you are encountering.
http://www.rowand.net/Shop/Tech/FordEFISwap.htm
I will be doing more research on this too so keep us posted, hope this helps.

Lourdalfe · May 11, 2017

That is interesting for sure and just like a lot of the members here have suggested he went with the mass air flow setup and not the speed density so it looks like I'll looking for a mass airflow setup

Lourdalfe · May 14, 2017

Ok if anyone has a pcm that would work for mas air and a automatic please let me know thanks Al

Lourdalfe · May 20, 2017

Ok so I picked up a a9p should be hear in a few weeks I need to find out if the harness from the 87 crown Vic will work with the mass mod done to it or do I need a mustang harness and also witch mass to get with this pcm any help would be great thanks Al

Lourdalfe · May 28, 2017

Ok so put in a a9p pcm and the mass air conversion wiring and a 90 mustang gt mass air meter started the car and it ran like foring order is off havent pulled codes yet but will in the morning

jrichker · May 28, 2017

The non-HO firing order in the Crown Vic wiring will have the injectors squirting at the wrong times. You'll need to move some of the injector pins in the black 10 Pin salt & pepper shaker connector to match the HO firing order.

See the graphic for the 10 pin connector circuit layout.

The following are diagrams courtesy of Tmoss & Stang&2birds

Complete computer, actuator & sensor wiring diagram for 88-90 Mass Air Mustangs

Lourdalfe · May 28, 2017

The crown vic harness is the same as the ho engine just checked and pins are all in the right places my current problem is that it will start and run but won't rev past 2500 rpms or idle for long and when the iac is plugged in it dies the guy I bought the pcm from says the pcm was th fault new fault codes are 23 and 95

Mstng93SSP · May 29, 2017

Maybe this has been addressed, I'm not sure as I am a "skim" reader kinda guy. But if this is in a 65 Mustang, wouldn't it be a whole lot easier to throw a carb on there and be done with it?

Lourdalfe · May 29, 2017

Lol yes it would be but I'm looking for better drivability and it's become somewhat of a challenge now I'm close to getting it solved but running into some snags is all and now I'm thinking maybe the new fuel pump has gone bad

jrichker · May 29, 2017

Lourdalfe said:
The crown vic harness is the same as the ho engine just checked and pins are all in the right places my current problem is that it will start and run but won't rev past 2500 rpms or idle for long and when the iac is plugged in it dies the guy I bought the pcm from says the pcm was th fault new fault codes are 23 and 95

Do an end to end injector wring test to make sure that the injectors are properly sequenced for a HO engine and computer.

The HO firing order is 1-3-7-2-6-5-4-8.
Non HO firing order is 1-5-4-2-6-3-7-8

HO wiring end to end continuity check. This will verify that the computer and engine wiring harnesses are correctly wired for a HO fuel injector wiring scheme.
Disconnect the main connector from the computer and pull it down so that you have good access to the computer side of the connector.
Place one voltmeter lead in pin 40 or 60 - they are both the main computer power ground. This lead does not change for any of the tests
Disconnect all the injector connectors from the injectors.
You will re-connect them one at a time to do the testing. Once you have checked an injector lead, disconnect it before testing the next injector. Fail to do this and you will get incorrect results

Turn the ignition switch to Run
Check pins 37 & 57; you should see 12 volts.

Computer wiring harness connector, wire side

Computer wiring harness connector, computer side side

Here are the HO injector wires that are different; check to see that you have 12 volts on them one at a time.
Connect injector #3, look for 12 volts on pin 12 on the computer. Disconnect the injector connector from the injector before testing the next wire.
Connect injector #7, look for 12 volts on pin 42 on the computer. Disconnect the injector connector from the injector before testing the next wire.
Connect injector #5, look for 12 volts on pin 14 on the computer. Disconnect the injector connector from the injector before testing the next wire.
Connect injector #4. look for 12 volts on pin 13 on the computer. You are finished now and can reconnect all the injector connectors to the injectors.

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)

See the graphic for the 10 pin connector circuit layout.

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.

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

Lourdalfe · May 30, 2017

Ok a good update but one that now pisses me off lol the fuel pump started sounding funny after putting in the mass air flow kit and I thought that to be strange so I checked voltage because jrichker with all his info gave me the thought to check and make sure that everything is getting the right voltage so I did and it was so I pulled the pump figuring it had to be bad even though I just bought it in June of last year and I never drove the car and found the the rubber line going from the pump to the pump bracket inside the tank had a split in it and probably has been my problem all along took the pump back on warranty replaced it and now the car runs great thank you to all that have been helping to figure it out especially jrichker ill let you all if there is anymore fun thanks again

jrichker · May 30, 2017

Lourdalfe said:
Ok a good update but one that now ****es me off lol the fuel pump started sounding funny after putting in the mass air flow kit and I thought that to be strange so I checked voltage because jrichker with all his info gave me the thought to check and make sure that everything is getting the right voltage so I did and it was so I pulled the pump figuring it had to be bad even though I just bought it in June of last year and I never drove the car and found the the rubber line going from the pump to the pump bracket inside the tank had a split in it and probably has been my problem all along took the pump back on warranty replaced it and now the car runs great thank you to all that have been helping to figure it out especially jrichker ill let you all if there is anymore fun thanks again

I am glad to be of service. Warm, sunny days are here for most of us, so enjoy your Mustang, you have earned it.

Run Problem

General karthief

wonder how much it would cost to ship you a pair

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You have a nice rear end there Dave.

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Run Problem

wonder how much it would cost to ship you a pair

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You have a nice rear end there Dave.

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