Flashing SES and weird surging
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Well for the last couple weeks when the engine is cold and I start it. It surges, 500-1200rpm or so and runs rough and sometimes dies... then kinda smooths out after a minute or so. Then I rippped my half my exhaust off not fasr from left long tube and was on my way to have it fixed today and suddenly it got really ballless below3000rpms and then WOULD SURGE and go back to down whilest the SES was flashing, and running horribly rough... Then at a light just before the exhaust shop it went away and hasn't came back... Any idea whats going on here? I have no internal mods such as a that I know of (bought not long ago). But I belive the PCM isn't stock, because when I plug it in it says its a 2002 with a different VIN... Mine is a 01... Maybe I need a a new tune.
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Flashing SES is due to a serious misfire. Misfire could be due to a lot of things, anything from a damaged plug/wire to a bad coil to more serious stuff like a bent valve.
I'd start by getting it scanned and see what codes pop up. I'm sure you'll have P0300 (random multiple misfire), but you might also get a P0301 to P0308 (the last digit signifies the cylinder that's misfiring). That way it may help to point you to the cylinder that's having the issue.
I'd start by getting it scanned and see what codes pop up. I'm sure you'll have P0300 (random multiple misfire), but you might also get a P0301 to P0308 (the last digit signifies the cylinder that's misfiring). That way it may help to point you to the cylinder that's having the issue.
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What sort of scanner are you using?
To the best of my knowledge, the only codes/condition that can cause the SES light to flash is a misfire.
To the best of my knowledge, the only codes/condition that can cause the SES light to flash is a misfire.
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Mine did that, when i scanned it came up with code P304 i believe... which was a misfire...took off valve covers and discovered i BROKE a pushrod in 2 pieces, so that was causing that cylinder to missfire...hope its not as serious as mine..sounds like fouled plugs or bad wires...best of luck.
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I had a similar problem a little over a year ago. It would let out a little smoke, run rough, and it was sucking the gas (More than usual!) I took it in to a shop and it turned out that my injector was sticking open and flooding the cylinder. They told me I was lucky that it did not wash it out. Let me know how things are going!
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Sorry, I also forgot to mention that I thought maybe it was my O2 sensor as well. I replaced them with O2 simulators, but needless to say, that was not the problem!
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It sounds like you have the same problem i got right now, i changed out all my plugs and the fuel fliter but its still not running right.
did you find out what your problem is?
did you find out what your problem is?
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Keep in mind the injectors, it could be possible that one or more are clogged. The only way to check, as far as I know, is to look into the history of the code, which may show if the cylider was under a rich or lean condition.
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Moving to General Maintenance & Repairs.
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An EGR valve that's stuck open will cause random misfire at low RPMs... but I kinda doubt that's your problem. Are there any more codes showing? I bet we could help a lot more if you'd list exactly what codes are showing. Oh... and oxygen sensors are important... if you have problems there, you should probably replace them.