Random Surging? Please Help..

[thesargster4]

Hey guys.. Ive got about 400 miles on my 95 v6 since ive gotten it up and running.

First this in the morning the car runs like a top, and about 90% of the rest of the day it runs the same.

But when i drive it for about 15+ mins and get it warmed up, if i let the car sit for anywhere between 10 to 30 minutes and go to start it, it surges and smells like its running rich, and feels like its miss firing. Once i put it in gear and hit the gas, it goes away after about 10 seconds.

So far ive replaced:

Fuel injectors (went to 19 /lb hour);
Crank sensor;
FPR;
Fuel Filter;
all vaccum lines (ive been over vaccum millions of times, no leaks.);
Spark plugs (did go 1 heat range hotter for the bigger injectors.. same plugs for a 88 GT);
Spark plug wires;
new cold air intake;
MAC O/R H-Pipes, Flowmaster cat backs;
EGR Valve;
EGR Vaccum solenoid;
Coolant temp sensor(s);
Thermostat;
Also had the ECM checked.

I'm starting to think it has to do something with timing or ignition. Possibly my coik pack going, or something in that nature. Ive done pretty much everything to do with induction, exhaust, fuel, and vaccum. I havent done anything with ignition besides the wires and plugs..

Please give me a word of advice on this one.. Much appreciated,

John

 

[hollywoodstang]

Can someone move this to 94-04 V6 Mustang ? This guy needs help and i hate to see this guy not get any replies. Thanks

 

[BlownFiveLiter]

Can someone move this to 94-04 V6 Mustang ? This guy needs help and i hate to see this guy not get any replies. Thanks

Done

 

[HISSIN50]

Have you viewed PIDs while it is acting up? You might find you have a sensor (ECT, et cetera) that is heatsoaking and causing the A/F trim to be off upon a hot-restart).

 

[thesargster4]

Sure havent, i dont have the money to get that done.. so i was trying to seek into someone that has had the problem.. any other advice?

 

[MustangLX-5.0]

Couple things you can do.G out and buy an OBDII scanner (about $80 for a basic reader) or just run to your local Advanced Auto Parts store and ask if you could use the scan tool.They'll usually let you go out and use it for free (since your vehicle is right outside).

It sounds very possible for a bad ECT causing the PCM to over compensate on ST fuel trim.Have you noticed any difference in how it runs at different times of the day? Such as heavy dew (water vapor high) in the early AM.A fouled up MAF sensor could also be the culprit.Maybe not fouled up,but perhaps the CAI may have something to do with it.Did your CAI relocate the MAF?