Need help 95 GT runs like crap

I just got a 95 Gt5.0, it didnt run when i got it, went through alot but now it runs, but it had a weird problem and im lost. A little back info, when i got it the original owner said it had a bad fuel pump, so i put a new pump, it started but ran like the timing was way off, no power, revved slow, was popping through intake. The car has 200k on it, so i went to check timing and realized it had alot of new parts, someone has been chasing this issue. New distributor, cap and rotor, new wires, new IAC, new tps, i put new plugs. Tried resetting timing but it was all over the place, pulled timing set chain was sloppy, new timing set. Now heres the weird part, when i started it first time after timing set, i forgot to plug in the maf, started perfect, reved like it should no missfire, after a minute or two it went into limp mode i plugged the maf back in and runs like crap again. Replaced the maf, runs way better but still randomly starts running like crap and popping again. Im out of ideas. When i changed the timing set i also added a new harmonic balancer. Any help is greatly appreciated.

Extra info, compression test showed 160-165 across all cylinders, fuel pressure holding 38-40, timing set at 14 with connector out. Issue is only between 1k-2k rpm runs clean about that.
 
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I just got a 95 Gt5.0, it didnt run when i got it, went through alot but now it runs, but it had a weird problem and im lost. A little back info, when i got it the original owner said it had a bad fuel pump, so i put a new pump, it started but ran like the timing was way off, no power, revved slow, was popping through intake. The car has 200k on it, so i went to check timing and realized it had alot of new parts, someone has been chasing this issue. New distributor, cap and rotor, new wires, new IAC, new tps, i put new plugs. Tried resetting timing but it was all over the place, pulled timing set chain was sloppy, new timing set. Now heres the weird part, when i started it first time after timing set, i forgot to plug in the maf, started perfect, reved like it should no missfire, after a minute or two it went into limp mode i plugged the maf back in and runs like crap again. Replaced the maf, runs way better but still randomly starts running like crap and popping again. Im out of ideas. When i changed the timing set i also added a new harmonic balancer. Any help is greatly appreciated.

Extra info, compression test showed 160-165 across all cylinders, fuel pressure holding 38-40, timing set at 14 with connector out. Also the missfire and running bad only happens between 1500-2k rpm runs clean about that.
 

alutwon

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Dec 10, 2020
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The computer could need a reset or it might be faulty, considering everything else has been replaced you may want to look at that. Second, the car is 27 years old so you might have a loose wire somewhere. best of luck
 

Noobz347

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I will assume that the all the fuel you are running is brand new.


That aside, it looks/sounds to me like you have a vacuum leak someplace.

Clear the cam / Reset the EEC by pulling the battery, pushing on the brake a few times, and going to have a smoke while it sits for a few.
Come back and start it with everything plugged in - Triple check this
Once it had time to get warm and run for a bit, shut it down and pull Engine Off codes. Let's start there.

I predict you will get an O2 code and possibly a MAF code.


Let us know what you come up with and good luck!


Also.... Since it's a 95... This might help you greatly:



Step by step... You will find the issue(s) :nice:
 
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Anyone have an idea whats this is called and if can cause my problem its almost the only thing that hasnt been replaced, looks like a old school condenser but cant seem to find it anywhere
 

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Ok guys alittle update, been going through the check list and checking codes as i make repairs new codes have popped up 565 canister purge, 10 which i cant seem to find, and 212 spout ground, car runs like a beast when cold and starts sputtering again when warm.
 

dcm0123

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Mar 11, 2017
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Check to verify the canister purge valve opens and closes as it should by applying power to it. Do not leave the power on for more than a second because I am not sure if it is a 5V or 12V coil. I am not sure if power opens or closes it. Pull the RH inner front fender and make sure there are no broken hoses going into the canister.

Pull the hose off the side of the purge valve going to the purge canister and install a short hose on the valve with a bolt in the end to plug it. Leave the hose going to the canister open. Loosen the gas filler cap so it will vent through the cap and drive the car to see if it improves how it runs. If it does not, the canister is not loikely causing your run problem.

Here are a couple of links to look at for the spout connector. Is the spout plug in place which is removed to time the engine?



Mustang-94-95-IgnitionControlModule.gif
 

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Check to verify the canister purge valve opens and closes as it should by applying power to it. I am not sure if power opens or closes it. Pull the RH inner front fender and make sure there are no broken hoses going into the canister.

Pull the hose off the side of the purge valve going to the purge canister and install a short hose on the valve with a bolt in the end to plug it. Leave the hose going to the canister open. Loosen the gas filler cap so it will vent through the cap and drive the car to see if it improves how it runs. If it does not, the canister is not loikely causing your run problem.

Here are a couple of links to look at for the spout connector. Is the spout plug in place which is removed to time the engine?



Mustang-94-95-IgnitionControlModule.gif
Yea spout connector is in place checked connector wiring also, distributor is new, ignition module new, im starting to suspect the ecu based on this wiring diagram.
 
This things making my brain boil, just drove it, miss only happens engine is loaded, like it will run fine in the driveway as soon as you drive it, then between 1500-2000 it bucks for a second or two then power all the way through the rpm range.
 

dcm0123

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Erase the codes.
When you get code 10,depress the accelerator al the way to the floor but not to fast (take 2-4 seconds. This checks the throttle sensor which may be the cause of your issue. This is an engine not running test.
Read codes again.
 
I GOT IT!!!! Thank you guys so much for all your help, today i was reading the book for the scanner i got it said code 10 was cylinder 1 problem, went to check the timing and the timing light randomly quit flashing. Brand new cap and rotor bad, put the old ones back on missfire gone, i also deleted the egr, not sure if that helped but so far so good.
 
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