Questions and Answers
Geo Engine Code
Q. I just bought, as in yesterday, a little Geo Tracker, runs great, the guy at Jiffy Lube went on and on about how well it had been taken care of. BUT the service engine soon light came on...he hooked up a little machine to it and got a code 400.He said it wasn't a big deal and made the light go away, but the next day the light was back on. Is this '400' going to ruin my car? 1996 Geo Tracker.
Thanks for any information you can offer.
TammyA. The 400 code indicates a bad Exhaust Gas Recirculation (EGR) valve. While this would not impair the performance of the vehicle, unless it was stuck open, it should be repaired because it does lower the exhaust emissions of your car.
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