jcv22jr

Does anyone know why a "Service Engine Soon" light would come on and what I can do about it? It's been 15 degrees +/- in the morning, car was warmed up, been driving for about 30 min. and then light goes on. I come to a stop and engine seems like it is still slightly accelerating and causes the car to move forward a bit so I have to hit my brake harder after I have already come to a complete stop. Then I put the car in park and it seems like the engine is revving slightly? Any advice is much appreciated. Thank you!

2002 Trailblazer LT
96,000 miles +/-

RonH

The light is coming on because the computer has detected a condition that needs attention. Go to an Autozone, Oreilly's or Advanced Auto Parts store and get them to use their reader to check the error codes. They will do this for free.

jcv22jr

Ron,

Thanksfor the advice about having the codes read at Autozone. Here's another question for anyone. Here's what came up:

P0172 "System too Rich (Left Bank or Bank 1)" (Once)
P0340 "Camshaft Position Sensor Circuit Malfunction" (Twice)

Does this mean I shoud replace my Camshaft Position Sensor? What does system too Rich mean? Is this something I can do following my Chilton's Repair manual or should I just take it to the dealer to be safe? Any advice would be helpful? Thanks in advance for all your help!

-C

golfer

Your cam position sensor is part of the timing cycle of when and how much fuel the injectors spray.
The system too rich is because of too much unburned fuel present in the exhaust and the O2 sensor is detecting this.