Help

[Richard Lee Ledesma]

I've recently replaced distributor cap, wires, plugs and oil and oil filter. My service engine soon light still flashing I've also replaced o2 sensors any other idea's what it could be. Runs a little ruff from stop to about 20mph but no problem after that. It is a 1999 gmc 1500 suburban with about 225,xxx miles

[dsr611]

Need to know the codes that are present

[intheburbs]

Flashing CEL is a misfire detected.  If it was me, I wouldn't be driving it until I found the cause.  You might be causing damage to the engine.

[Supreme Pizza]

20 hours ago, Richard Lee Ledesma said:

I've recently replaced distributor cap, wires, plugs and oil and oil filter. My service engine soon light still flashing I've also replaced o2 sensors any other idea's what it could be. Runs a little ruff from stop to about 20mph but no problem after that. It is a 1999 gmc 1500 suburban with about 225,xxx miles

 

    I would go to the nearest auto parts store and ask them to check the "OBD2 codes". Then post those codes in this thread. 

 

   As for driving it will a bad misfire - than can damage your catalytic converters if you drive it too much. The unburnt fuel in the cats is not good. 

 

   Also, stop guessing. DO NOT replace parts unless they are bad. You only waste money, and can actually cause the problem to get worse. Lets say you have a misfire that is caused by a bad coil. You replace the plug wires, but one of the new plug wires is defective. Now you have 2 problems. Even when you do fix the coil, now your hunting for the other problem, but you automatically discount the wires as the issue, because you just replaced them. 

 

    Don't throw parts at something. Being a mechanic is 99% troubleshooting.

 

   Replacing the defective parts is done only AFTER the issue is successfully diagnosed.