Lately when I'm driving on the highway for more than about 15 minutes or so, the 'service engine soon' light has been coming on. The car seems to be running fine, no weird hints in the guages of anything odd going on...the light just comes on then if I keep driving, it goes off around 10-15 minutes later. I was reading another thread on the board and someone mentioned changing the oxygen sensor when gas mileage starts to go south. I was thinking maybe this has to do with that light coming on? Lately I've been getting around 180-190 miles per tank with mainly city driving and maybe 30 or so of that on the highway (if that). The only mods to the car are in the sig. ... Any suggestions of what might be causing the light coming on and the poor mileage? Thanks.

 

Once the SES light comes on, the problem code is stored in the PCM.... at least until the car has been operated many times without the problem recurring. Get it scanned, and they can tell you exactly what caused it.

Just guessing, I'd say it might be the EGR valve..... but why guess?

 

get a scanner. trust me they come in usefull. unless you know someone with one or can get it scanned for free.

 

Yeah unless you can get your scanned for free i would get a scanner. It may cost a bit more upfront then just getting the car scanned 1 time but it is well worth it. I paid $100 for the damn dealer to do it for me and they did a bad job and i had to bring it back to them 3 days later. I had to b*tch with the manager not to charge me again. After another scan which didn't help i decided to just buy a scanner. It has to be the most usefull tool for my car i purchased.

 

OK cool....so where can I find one inexpensive and what brand scanner do I go with? I've seen what I think is a scanner that fits in the A/C vents in a z28...or do I get something else that plugs in and doesn't stay in the car? Kinda new to computer cars

 

Go to AutoZone...around $170 to loan it to you. Get money back when you return it. Actually they will let you scan it for free in the parking lot and then just write down the errors.. easy as that...