I keep throwing the check engine light at 70mph in 6th gear, why? It only happens if i keep it constantly at 70 in 6th gear, like its running at to low of a rpm or something. Performance wise nothing changes, and when i shut it off, then start it the light is off. it usually take 5-10min in 6th gear to throw the light? any idea?
Yea i use 92 octane also

 

Do you still have the EGR system? Might be related to that. But why guess... put a scanner on it and find out the exact cause. The code will be "stored", even if the SES light isn't on.

 

I believe i still have the EGR, can I just up and do away with it? Ill have my friend scan the car sometime soon

 

No good reason to remove the EGR, and if you do, you will get a constant SES light, unless you also have it programmed out of the PCM, or wire up a simulator circuit to fool the PCM into thinking its still there.

 

Mine used to do that too. If you remove the EGR, and leave the solenoid connected you wont get an SES light on a 95. I didn't get any more bad readings after that. I got rid of my EGR and AIR when I did headers, and since I see you are going to do headers you may as well do the same.

 

I actually have the same problem and it is the EGR code that is thrown. I can be in fifth gear doing XX amount of speed and then drop it into sixth and maintain XX amount of speed, but the SES light will come on. Is it just clogged ports? The valve is new as is all the vaccum hose since I just installed my LE H/C. Any thoughts?