i really need some help/advise for my 95 gt

[larrylass]

I have a 1995 mustang gt 5.0 motor and did some mods recently; trickflow street heat intake with a 65 mm throttle body. bbk shortys with a bbk x pipe.when i drive the car it will run perfect for about 3 minutes and then it starts to mis fire horribly and detonate.when the car cools off the same thing happens again. WTF ive changed throttle position sensors twice and set the voltage from .90 v to 1.00 v. i know .97 v is ideal and this is where its set. the EGR is unhooked along with all smog related parts. they were all un hooked before the mods and the motor ran fine. ive also changed the IAC twice not that that would do anything and my o2 sensors 3 times. I just cant figure out why the car starts to misfire and detonate after 3 minutes. Ive also cleaned the mass air meter 2 times with a non clorinated brake cleaner. Im just at a loss and need you guys help PLEASE!!! ps yes all the plug wires are on correctly

Thanks
Larrylass

[~The Jester~]

Had a good look at your pistons lately? Sounds to me like you have a carbon build up/hot spot on the slugs.

Not sounding like "electronics" to me, sounds more mechanical.

[larrylass]

Not when ive run n2o man. heres the problem the computer is coming out of wake up mode after 3-4 minutes and goes into a closed loop mode. Ive checked for vac leaks "19 hg of vac at idle then will drop when reved and shoot back up when throttle is released". One person suggested that the Constant Control relay module may be bad.Its a 150.00 to find out though. i set the tps voltage to .097 with the throttle blade closed and then set the idle .Is this correct?? ive read every which way to do this and remember that the 94-95 tps is non adjustable and impossible to get to when the throttle body is on the motor. im about ready to rip this f----- computer sh-- off this car and carb it and be done with this Bull ----

big lar

[94snake]

ive had much success with aftermarket EFI.... on your throttlbody, should be a pocket on either side of the tps wher flat screw driver can slide in ....as long as your tps fastners arnt too tite...should be able to lossen top fastner, from there Patiently , slightly bump either direction as desired voltage is achieved With key on ...engine off ...seek your 5v and your .98 v. hey bro carb is nice and cheaper ,but you will never beat the tune ability and fuel mileage of EFI. hope this helps PhiL

[larrylass]

thanks for the reply!! do you set your tps voltage with the idle speed already set or with the throttle body blade closed completely??. i made the idle speed adjustable with the screw on the side of the throttle body.Can the tps cause the condition ive described in the 1st threads??
Thanks again
larry

[Dark_5.0]

I think the module on the distributor is bad. (The box all the wires plug into on the distributor.)

[vristang]

You should reset your tps after setting the idle speed, but most likely the tps is not causing your problem.

Have you pulled the codes?
You may get a full pass on the codes, or you may get that a particular sensor is out of range. Never know til you try.

EGR computers will add timing when the EGR is supposed to be functioning. If you unhooked the EGR and did not turn off the EGR functionality in the computer, you could be getting more timing than the motor can handle.

Oil deposits are also a possibility, as suggested by thejester.
Check your TB/VC hose and PCV hose. If these hoses are wet with oil then you need to consider that oil is entering the intake tract via those routes.

jason

[larrylass]

thanks for your response VRI stang. i have a chip that turns off the egr and the PCV hoses are dry. tb/vc ? whats that? i have 2 small vacumn ports towards the intake on the Tb, one goes to the adjustable fuel regulator and one is plugged. is this what your talking about?? Ford tech line seems to think its the TPS so ill go adjust it again for the thousandths time.It just baffles me as to why the car will run perfect for the first 3-4 minutes and then start missing and running lean after that. The guy that did my chip "hes in Mississippi and im in NJ" suggested that the "Constant Control relay module" may me bad. No i dont have a code scanner but autozone does so ill go get some codes on sat
. Thanks again for all you help guys i really apprieciate it

larry

[redsn95vert]

This may be a dumb question, but......What temp t-stat are you running. I've seen tons of guys pull their hair out with the same problem, only to find out that they are running too cool of a t-stat. Unless you have your chip programed for it, you don't want to go below 180.
Good Luck..

[Dark_5.0]

Originally Posted by Dark_5.0

I think the module on the distributor is bad. (The box all the wires plug into on the distributor.)

Once the ignition module heats up it causes the problems you are describing when its going out.

Been there done that.

[larrylass]

i have a 190 degree temp thermostat and i have 2 ignition modules.2 caps ,2 rotors, 2 sets of wires ,2 coils ,2 tps`s 2 IAC`s 3 sets of 02 sensors. tried both of everything same thing augggggg!
Thanks again for your help
larry

[Dark_5.0]

Originally Posted by larrylass

i have a 190 degree temp thermostat and i have 2 ignition modules.2 caps ,2 rotors, 2 sets of wires ,2 coils ,2 tps`s 2 IAC`s 3 sets of 02 sensors. tried both of everything same thing augggggg!
Thanks again for your help
larry

I would swap out computers and see if that helps.

[vristang]

Originally Posted by larrylass

thanks for your response VRI stang. i have a chip that turns off the egr and the PCV hoses are dry. tb/vc ? whats that? i have 2 small vacumn ports towards the intake on the Tb, one goes to the adjustable fuel regulator and one is plugged. is this what your talking about?? Ford tech line seems to think its the TPS so ill go adjust it again for the thousandths time.It just baffles me as to why the car will run perfect for the first 3-4 minutes and then start missing and running lean after that. The guy that did my chip "hes in Mississippi and im in NJ" suggested that the "Constant Control relay module" may me bad. No i dont have a code scanner but autozone does so ill go get some codes on sat
. Thanks again for all you help guys i really apprieciate it

larry

Your computer does not require the tps to be reset. Why the Ford tech would say that is beyond me.
The computer constantly resets the base/idle tps reading. The only impact that it would have is if you were out of the acceptable range of .6v-1.2v.
WOT is set to 2.7v above that base reading.

TPS setting is not your problem.

Find out what the codes are.
I am suspicious that you have an ACT/ECT sensor getting out of range.

If not then the chip you have may be messed up.
Have you pulled the chip, reset the KAM memory by unhooking the bat, and tried that?

Closed loop switching should happen quicker than 3-4 minutes, but that will depend on driving conditions, air temps, etc.

I have never heard of a Constant Control Relay Module.
If this guy can describe what it is, great.
If not I think he is full of BS.


Pull the codes and let us know what they are.
Get the tps set to just under 1v. Any more accuracy is a waste of time.
Try removing the chip, and see what happens. Be sure to reset the KAM. This is the unknown variable right now.
I wish I could help more.

jason

[larrylass]

vristang- the CCRM is the box by the radiator on the passenger side. it kinda looks like a smaller ECM. Anyway here are the codes ,i did the EEC self test and was confused as to the pauses between the blinks of the CEL Stock setting on the ECM chip KOEO
32,75,52,55,35,58,56,56,21,62,26,52,32,75,52,55,35 ,58,56,56,21,62,26,52
should be: 327,552,553,558,565,621,622,652, repeat 327,552,553,558,565,621,622,652

327 - DPFE or EVP circuit below minimum voltage of 0.2 volts
552 - Air management 1 circuit failure (AM1/TAB)
553 - Air management 2 circuit failure (AM1/TAD)
558 - EGR Vacuum Regulator circuit failure
565 - Canister purge circuit failure
621 - Shift solenoid #1 circuit failure
622 - Shift solenoid #2 circuit failure
652 - Modulated Converter Clutch Control solenoid output circuit error
_________________________________________

and Stock setting on the ECM chip KOER
4,31,43,11,32,75,36,63,23,14,31,13,27,53,66,32

should be: 4(8-cyl id), 314,311,327,536,632, repeat, 314,311,327,536,632

314 - Thermactor air system inoperative (left side)
311 - Thermactor air system inoperative (right side)
327 - DPFE or EVP circuit below minimum voltage of 0.2 volts
536 - Brake On/Off circuit failure / switch not actuated during KOER test
632 - Overdrive cancel switch not changing state (E4OD)
_________________________________________

All the codes are compatible with the deletion of the smog and EGR components...aside the last 2 KOER codes (operator error on 536, 632 is due to AODE electronics been eliminated)....they all have a cause.....their deletion

This was an answer from another forum i posted in . the 2 digit #s are the ones i came up with and i checked them 3 times for accuracy. they are in the exact order that was flashed. the 3 digit #s are the ones that a person deciphered as to my reading the codes wrong. i hope these codes help you understand . Thanks again i really apprieciate your help

Big Lar

[larrylass]

got it fixed Man!!!! between you guys and the guys over on my5.0.com it was determined to be a bad distributor. Changed it out and the car runs perfect. Thanks alot to all who posted ,i learned alot about my car ,EFI and met a great bunch of guys!!! i mean it thanks a million and i hope i can help some one as well as you guys helped me!! anybody run at Atco raceway in NJ??

Big Lar

[vristang]

Awesome Big Lar

I'm glad to hear you got it fixed, cause now I'm off the hook.
I really had no idea where to go next.

What was it that directed you to the dist?
I am curious how the dist was determined to be the problem.

Now what are you going to do with all those extra sensors

jason

[larrylass]

ill just keep the extra sensors ) any way the was alot of black dust under the vane in the distributor. Between that and seeing the timing mark jump around 2-4 degrees it was determined that the rotor vane was hitting the magnetic sensor . Go figure that this would happen as son n as i did some mod unrelated to the distributor. Your advise on the TPS was dead on. I mean how many time s can you adjust something thats unadjustable??if it were that finicky it would be adjustable.i learned an awful lot about my carwho knows maybe Tweecer rt next?? thanks again

Big lar