93 grand am

Have had 93 grand am, 4 cyl, ohc, several years. Last 2, 3 weeks, the service engine soon light comes on, and car will run just a little rough, but not to bad. Light sometimes will stay on for a good while, other times just a few seconds. Have practically new coil, coil housing, plugs, boots. Car has 147,000 miles, always given good service. Is this maybe a sensor problem, or exactly what should I check. Thanks for any info.

Reply to
Tom
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I had the same problem. Does your radiator fan go on a few moments or so before the light goes on? Or do you hear a whirring noise coming from the engine compartment before the light is on?

This does sound like a sensor problem (oxygen and coolant temprature sensors are what failed in my car).

If you have an AutoZone in your area, they could check the engine blink codes for you and give you a listing of the things to check. When I had mine done in March, the guy circled the two sensors that need replacing on the printout so I knew what to buy. The engine light will have to be on for them to check. Usually they wait a few moments and the light will go on again. AutoZone provides the engine blink code check service for for free.

I'd at least get the blink codes analysed first before you go replacing anything. That way you won't spend a heap of money on parts to find it wasn't what was wrong. :)

-- [*]~ Fuzzie Dice ~[*] My KITT: 1987 Pontiac 6000 w/ 145,000+ Miles

Reply to
FuzzieDice

You might want to look for bad vacuum hoses.

Reply to
Scott Buchanan

As stated, check the code(s) and go from there. A sensor has picked up unusual activity, or the sensor itself is faulty. But reading the codes will give you a starting point.

If there isn't an Autozone or similar place nearby, it should be possible to check the codes yourself. Ignition on, engine off, connect A and B terminals (Upper right) on the diagnostic plug (below steering column). It will flash a test mode code at you three times, then begin to flash whatever code(s) are stored. You can also visit

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for more instructions on how to do this.

Reply to
Tony V.

I also have the same problem, but haven't done anything about it yet. The 'service engine soon' light doesn't stay on long enough to test.

Symptoms: I have a '93 Pontiac Grand Am 4 cyl ohc, bought it in '94. (152,000 mi)

The 'Service Engine Soon' light comes on during a hot start. (After I've driven it for at least half hour or more) This has happened ONLY 4 times over the last

3 months. What happens is after starting up the car, the 'Service Engine Soon' light comes on for about 6 seconds then goes off. (I've noticed a rough idle at times)

After that the car seems fine.

Anyway, thanks to everyone who responded to Tom's post.

Reply to
Aaron0617

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