I already replaced my EGR valve and EGR solenoid along with new IAC new o2 sensor and fresh hoses. My 1986 trans am passed beautifully throguh emissions.

i drove it up and down the highway to go get the test done. about a 20min drive one way.no engine light or anything.

a week later i take it down the highway again to a different town to pick up junkyard parts and i noticed my check engine light on doing about 70 and about into my trip. temp and oil was fine

i'm not sure if it means anything. ive taken the car up to at least 40 on back roads no light since that one day. its parked for winter and never got it back up to 70.

just curious for thsoe who really know engines, if theres any kind of mechanical significance or sensor that is supposed to turn on or has a role in the higher speeds that would cause the engin light to show up at high speeds?

it may just be a fluke and mayeb a loose connection but i figured wouldn't hurt to ask

thanks.

 

Jump the ALDL and get the code out. The ECM stores them for like 50 restarts after it trips the light. Unless it's been started and shut down quite a bit since this happened (or the battery disconnected) there's a good chance the code is still in there.

 

ok cool thanks I didn't know that. I thought after the light is gone so is the code. but awesome will do

 

Well, you said you already replaced it, but the EGR is only active at a higher speed cruising condition....

 

yea i thought about the EGR too the car passed emissions no problem with the new EGR and then 3 days later was my trip down the highway that gave me the light