Check Engine Light Continues to Come on In my Buick Rivieria – why?

Reader Question Thank you for your site. It is very helpful. I have a 1995 Supercharged Buick Riviera. I have had the fuel pump, transmission, brake module, radiator, water pump, fuel regulator, powertrain module,replaced and other things I am sure. the car has 143,000 miles on it so I would expect these things to go wrong.

Recently I have had the EGR valve replaced and the mechanic told me that the service engine soon light would still come on but he was not sure. He told me that my car stored a trouble code that there was no code for. He said the engine light might go on and it may not.

It has been going on and off because like you said every time your car starts it runs a self diagnostic test and if you shut the car off before it finishes the test the light may not come on at all. Can you help me out here. Also, When my car comes close to s top like at a light it makes this static sound. It does it sometimes as the car is in drive and my foot is on the brake. When I put the car in park the sound subsides.

Maybe I am paranoid, but i love this car and I have put a ton of work into it and Iw ant to do the right thing. Can you please help me out here. I want to do what is best for my car, and I will do what I must to keep it going well. Thank you for your time.

Sincerely,
John

Hello John,

I really need more info, like what code is being stored, what are some of the sensor readings etc. etc. to make an accurate guess. I would probably start trying to locate your noise first, and see if that is related to the check engine light. A vacuum leak comes to mind first that would produce a noise when you are on the brake, or at a stop light.

Pop the hood with the engine running and with someone inside with their foot on the brake and listen for a vacuum leak, and look for anything out of the ordinary, a vacuum line that is loose or broken etc. etc.

Next time the check engine light comes on, take it straight to the shop and do NOT turn off the engine so they can read the codes.

Keep me posted

Blessings,

Austin C. Davis