crappy starts and response on my 1995 Mustang SVT?

pk222 · 01-16-2009

hey guys, I've got a 95 svt cobra all it has is 3.73s and CAI. I recently changed the plugs wires cap and rotor. the plugs are autolite copper plugs and gapped to .054(what I was told was recommended). It seems like the car starts up crappy if its warm at all and the response is worse than my 89 gt. any ideas? it still has good power so I don't think the bottom ends going or anything. I just don't want to go threw replacing O2s the mass airflow sensor and everything to find out that wasn't the problem. I hooded up the scanner and the only thing that showed up was the IAT sensor had high voltage? I don't know if this could be the problem or not. I was also planning on getting throttle body cleaner and MAF cleaner.

thanks in advance

302Feen · 01-16-2009

Since you said it has a sluggish response then I would guess it would be that your timing is too retarted. Get a timing light and set it anywhere between 10*-14* advance.

MUSTANGRIDA · 01-16-2009

The gap should be 0.052

StalkerStang · 01-16-2009

I know its basic, but check your battery, have it load tested. The battery is a very important part of the car, especially an EFI car, you have a bunch of sensors all asking for a 5 volt and 12 volt reference, not too much a high output ignition system. My dad's 94 Cobra was starting slow and every now and then had light stumbles at lower rpm's. He has recently replaced the battery and it seems to be running better, even managed to pick up a couple mpg.

jerry9665 · 01-16-2009

Did you have poor starts and throttle response before you changed the plugs? Also make sure the rotor is seated properly. Cleaning out the MAF is a good idea too.

pk222 · 01-16-2009

the starts before were crappy thats why I replaced them but it wasn't all the time, the crappy starts were mostly when the car was already warm. but I'll check that the rotor is seated and clean the t/b and MAF. Should I redo the gaps to .052 or will it make that big of a difference? I just don't want to do it if theres not going to be a difference because they were a pain compared to my 89 gt to change the plugs.
I'll check the timing tonight and see what I can do with that. I run regular gas now I just don't want to end up having to run premium.
As soon as I can I'll have it load tested also.
does anyone know if this could be from the IAT sensor? I don't know if it meant that it was bad or what, it just said it had high voltage.

jerry9665 · 01-16-2009

http://www.allfordmustangs.com/forum...what-does.html

Not sure if I pasted the link right, but this explains the IAT's functions pretty well.

pk222 · 01-17-2009

I knew what the IAT was and did but I didn't know if it meant that it was bad because it had high voltage.

youmaytry · 01-23-2009

o2 sensors maybe? or it could be somthing with the maf, could be the o2 sensors throwing off a sensor

pk222 · 01-27-2009

sorry I didn't know anyone responded.
wouldn't those have shown up in the codes?

96moonlightblue · 01-31-2009

The o2 sensor or MAF would show up on code's i'm sure. If it got worse after changing those plugs and wires. I would go over everything. Make sure there is not a crack in the distributor. No plug wires got switched. (I don't this because then you would probabaly hace no power at all.) Also you might start it at night were it is good and dark and see if it is throwing sparks anywere from the wires cap or plugs. I don't know how many times I have done a tune up and gotten bad parts that were not insulated correctly or were defect from the get go it sucks but it happens.