Engine Light flashing on, then off

[crfs]

Hello
I've had quite a few problems with my 04, extended. This is only one of them.

I believe this has happened 5 times already - I'll be driving along (after noticing a little bit of a rougher ride than normal), and all of a sudden, the 'service engine soon' light comes on, for a second, then shuts off.

Everytime I bring it in, they find something - the last time (yesterday), they found no code, but I still have to bring it in.

Is this a normal thing?

I really am at my wits end with this truck - we've had it for not even 4 months, and it has been back to the 'mechanics' (I use that term loosely) at least once a month, if not two.

Thanks
CS

[zepcom]

Originally Posted by crfs

Hello
I've had quite a few problems with my 04, extended. This is only one of them.

I believe this has happened 5 times already - I'll be driving along (after noticing a little bit of a rougher ride than normal), and all of a sudden, the 'service engine soon' light comes on, for a second, then shuts off.

Everytime I bring it in, they find something - the last time (yesterday), they found no code, but I still have to bring it in.

Is this a normal thing?

I really am at my wits end with this truck - we've had it for not even 4 months, and it has been back to the 'mechanics' (I use that term loosely) at least once a month, if not two.

Thanks
CS

Might be a cylinder misfire... but that code should stick in the computer and keep the light on solid.

If you're near an Autozone, for free they might be able to hook up their ODBII scan tool and see the history of the codes... it might show up there. They often are also helpful in recommending what might be needed to fix said light.

Hope this helps...

Doug
ZEPCOM

[mparker10]

I have a 2004 Trailblzer that I have had the flashing service light problem. At first it would come on only when I had the cruise on, but now it comes on at other times. I have had it into the Chevy dealership, but they cannot find it. Apparently it does not register long enough to show anything but a misfire. If anyone can help me, I would appreciate any input.

[GMMerlin]

The problem you may be having is not an emission problem...ie a sensor or misfire causing the SES light to come on, but possibly an electrical concern that is causing an intermittant loss of power to the PCM. This will cause the PCM to "reset" (actually its like turning the key off and back on).
This condition may cause the SES light to flash on and off momentarily...because this is not an emissions related failure, a code will not be set.
Problem with these intermittant concerns is they are difficult to diagnose because the fault won't remain long enough for the technician to narrow the concern down to a specific circuit or componant.
This becomes frustrating for you the vehicle owner because it doesn't appear that the tech or dealer can find the source of your concern.
I would recommend that you keep a watch for when this concern occurs and note any relevent information (ie, drive time, temp changes or even other vehicle systems that may do strange things also) this will help in the diagnostic process.
Also the tech could call the technical assistance center or refer to other technican databases for similar concerns.