How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask sprinkles08 Your Own Question
sprinkles08, ASE Certified Technician
Category: Buick
Satisfied Customers: 21968
Experience:  ASE Master and Advanced level certified. Factory trained with 15 years dealership experience
Type Your Buick Question Here...
sprinkles08 is online now
A new question is answered every 9 seconds

My service engine soon light comes and goes. It is on for a

Customer Question

My service engine soon light comes and goes. It is on for a few hours to a few days then off for a few hours to a few days. The car has been serviced, the gauges all show normal and the car runs perfectly well and the same whether the light is on or off.
JA: Do you have the trouble code? Do you have a code reader or scan tool?
Customer: No, I don't.
JA: Not a problem. You can work with the Buick mechanic to figure that out. What is the model/year of your Buick?
Customer: It is a 2004 Buick Park Avenue Ultra
JA: Are you fixing your Park Avenue yourself? What have you tried so far?
Customer: I was told by a mechanic that it could be a problem in the emission control system and before spending possibly a lot of money to correct some of the possibilities I should try a new gas cap first. That didn't resolve the problem.
JA: Anything else you want the mechanic to know before I connect you?
Customer: That is all I know to tell him. This has been going on for several months. It will sometimes be on or off for several weeks and may come on or go off while driving along.
Submitted: 3 months ago.
Category: Buick
Expert:  david craig replied 3 months ago.

Hi Im David, thanks for visiting the site. first thing you need to do is have the computer scanned for codes. whether or not the check engine light is on or not there will be stored codes. autozone will do it for free for you. write the codes down and let me know what they are.

Expert:  david craig replied 3 months ago.

were you able to get the codes?

Expert:  david craig replied 3 months ago.

checking in to see how its going

Expert:  sprinkles08 replied 2 months ago.

Hello and welcome to JustAnswer!

The engine light will come on when the powertrain control module has seen a failure in a monitored component and sets a fault code. There are dozens of things that can turn the engine light on and it will take some testing to determine what is going on.

The problem could be anything from a spark plug or coil to any engine sensor, transmission issues, catalytic converters, a failure in the evaporative emissions system or even a loose or bad fuel cap; literally anything in the powertrain.

The first step in diagnosing the problem will be to use a scan tool or code reader to see what fault codes have set and then testing can be done from there.