Check engine light question, 90 suburban
Hey everybody,
I have a 1990 GMC suburban, with Throttle Body Injection, 5.7 liter engine, 2wd, 190,000 miles, needs to be smogged regularly
my question is what does the check engine light monitor??, the light doesnt come on right away, maybe 5 or 10 minutes after i start driving it, then on a long run it will turn off, then sitting at a light it will come back on, then turn off....turn on....rrrrrr
My assumption is that it doesnt monitor the o2 or egr sensor because i changed those last year and the light never came on, and ended up with better gas milage because the o2 sensor was bad........so what does that "check engine" light monitor???
thanks in advance for the reply's, i wont be able to check back on the thread until later today