I need help with my stang

candersts

New Member
Jul 14, 2005
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This is my first time posting,
I have a 95 GT that i have done most of the work myself, all the mods are in my signature. The problem: at low rpms it will occasionally misfire/stutter, it is not all the time. I have tried everything I know (chiltons/hayes manual i've got both) and can figure it out. If anyone can help me out or point me in the direction of a shop in my area (Silverdale/Bremerton) it would be much appreciated.
 
IMHO it's the B303 cam that is causing your issue. I bet above say 900+rpm the car is smooth as glass but when idling it feels choppy like its missing. With that 110*LSA the 94-95's will not idle smoothly. The EEC in our cars don't like it when the vacuum at idle is changed. Most adjust the idle to 900+rpm and live with it. Or, you could get a Steeda #19 cam with its 114*LSA and it will idle properly.

edit: B303 cam has a 112*LSA.
 
The plugs and wires are about 6 months old and still look good. It runs fine above 2000 rpm. I don't know how to describe it, it is almost as if the engine loses power for a second, it is too random to know exactly when it happens. I know the rough idle is the cam but it doesn't happen at idle.
 
JJ95GTID said:
IMHO it's the B303 cam that is causing your issue. I bet above say 900+rpm the car is smooth as glass but when idling it feels choppy like its missing. With that 110*LSA the 94-95's will not idle smoothly. The EEC in our cars don't like it when the vacuum at idle is changed. Most adjust the idle to 900+rpm and live with it. Or, you could get a Steeda #19 cam with its 114*LSA and it will idle properly.

edit: B303 cam has a 112*LSA.

Good suggestion, though I would probably not link the cam with his symptoms. I would, once he has ruled out a fuel issue, look at the TFI module. I had a very similar problem with my car about four years ago. I cleaned the plug for the TFI module, and solved the problem. My symptoms were the same as his, except my car was more prone to dying or stumbling at idle, or coming out of idle.
 
candersts said:
The plugs and wires are about 6 months old and still look good. It runs fine above 2000 rpm. I don't know how to describe it, it is almost as if the engine loses power for a second, it is too random to know exactly when it happens. I know the rough idle is the cam but it doesn't happen at idle.

Well this looks more like a problem I had with the throttle position sensor(TPS). It would start off fine then lose power for a bit and then take off again. Only at slower speeds and lower rpm. I replaced the TPS and all was well again.
 
The fuel pump and filter are about a year old, the injectors are about 7 months old. I drove around for about two hours, to see if there was any sort of pattern to it, none. It is completely random, if I jump on the accelerater with the rpms low it does it (but not all the time, just when it feels like it). It also does it when I am just cruising usually when I am in fifth cruising at about 40-50. and yes it throws me forward alittle but just as fast as it threw me foward it throws me back and takes off.
 
it might be simple as a loose wire some where. on the random part. i know my car right now has a similar problem but mine is spark plugs fuel fouling to much fuel at certain thorttle angle and engine speed all cuz i tryed a new plug now i have to go out and buuy some more
 
Scooby5.0Doo said:
it might be simple as a loose wire some where. on the random part. i know my car right now has a similar problem but mine is spark plugs fuel fouling to much fuel at certain thorttle angle and engine speed all cuz i tryed a new plug now i have to go out and buuy some more

Sounds like a certain balding person we know in a '99 cobra vert... he tried running Bosch plugs in his cobra and they fouled. He had to switch back to factory platinums.
 
Timming maybe???? Mine did kinda the similer thing and after i put the 255 holey fuel pump in never had a problem since? Maybe the fuel pressure ? I'm not to good at figureing things out by hear say but if i was there with you or riding/driving it i might be able to. buti to think maybe also another issue could be the MAF? peace



john :p
 
IMHO....

- pull the maf sensor and clean it (i dont think thats it, but it probably needs it anyhow)

- pull the plugs on the tfi, the coil, and the maf, make sure the wires are tight, and terminals are clean.

- pull and clean the idle air control valve

- check the plug wires and plugs for loose or broken, just for the heck of it...

- do the dash lights or headlights take a big dim when it happens?

- got gas anywhere out of the ordinary lately? - try some fuel dryer or a new filter just for the heck of it.

Just a few free ideas...
Dave-
:flag: :nice:
 
To add to the already good advise that's been posted:

Check the air tube between the throttle body and MAF for cracks or leaks as this can change the critical MAF signal.

If you can, scan it for codes. If you don't have a scan tool, PM me and I can tell you how to jump the test connector and count the flashes of the check engine light.

Not to beat a dead horse, but look very carefully at your plugs, wires and boots. Check for corrosion at the coil wire, coil and distributor towers. Look inside all the plug boots and on the sparkplugs for carbon tracks (escaping spark will usually leave a trace).

This is reaching a bit but I've had a worn distributor gear cause some really wierd problems. Unplug the timing plug (spout plug) and check the timing while fluctuating the rpms. It shoud stay locked and solid. If it's bouncing around, check both the distributor and camshaft gears for wear.

Try bypassing the MSD for a while. If it goes away, go though all the wiring and connectors with a fine tooth thingy.

If you clean the MAF sensor, don't use harsh chemicals and/or a stiff brush. The sensor elements (the two little resistors) are very fragile. I use glass cleaner and a fine paint brush.

If you give up, call the guys at BCA. 206-367-1471
 
I havent read the whole thread, but I have a '94 stang. cammmed and headded, etc. your issue began most likely with the trhottle body, then the cam amplified the situation, and a better frlowing set of heads/intakes will throw the stock calibrations off even more. our computers are very specific. changing intakes and exhausts will not make much problem, but often times a TPS (throttle position sensor) will be installed w/o calibration. then a bigger cam? forget about it man! the valve events are computed/fixed, w/ our comp. if you change the valve events, teh computer will be like "oh snap" all the time. Idle is the most difficult thing for an engine to do. everytime your motor fires at idle, it bounces off the stall limiter. :nice: