I have a 93 gt with a good many extras on the motor. Lately the check engine light has been coming on when i shut it off and then start it up. Or when i let it sit and idle for a little while. i backed the fuel pressure off a little to see if that was the problem and it still does it. I backed it off a little more the other day but haven't had a chance to see if it helped. Whenever the light comes on it spits and misses a little bit till i get it going and then the light shuts off and it runs fine. I was told it could the the o2 sensor. If someone could give me some advice it would be greatly appreciated.

 

it could be the o2s. take it to auto zone they will scan it for you. i have just had a few check engine codes recently on my 93. first was the mass air sensor which made it run like a sick dog, and then a throttle position sensor. with the maf sensor the light was on for a bit before it started acting up significantly. with the tps it started acting up before the light came on.

 

run a DIY koeo/koer test.. you can do this yourself, autozone ***** won't be able to do that as they'll try and use an obd II scanner[&:]

 

How do i do the test myself? What do i need to do?

 

List your mods, chances are If you have an Hpipe its your o2 sensors. Happens to me and I hate that light.

 

GT 40 intake, 24lbs. injectors with maf sensor,bigger fuel pump ( i think 210 lph), msd ignition, bbk cold air intake, bbk shorty headers, h pipe, 3.73 gears, eibach struts shocks and springs, bbk rearupper and lower control arms. someone told me to get a chip put in it to update the computer.

 

having an h-pipe has got nothing to do with the o/2 's on a fox making the light come on

 

here is how you do it yourself
http://myshifter.com/joel50/EECTEST.html