P0300 Code. Here's my issue and question.
#42
TECH Apprentice
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The vacuum leak has caused the engine to run false rich. it has been doind it for so long, that the cats have probably bit the dust(the sand hint hint). You NEED to fix the vacuum leaks, perform the tune up and probably replace the cats. At the very least drop the pipe and give them a visual inspection.
Chris
Chris
#43
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unplugging the tps will reset it, it needs to relearn which is why the idle surged and then levelled out.
Sounds to me like a vacum leak + clogged cats from a bad tune.
My recommendation....replace all vacuum lines (w/heater hose...cheap and easy), replace spark plugs. If still running like crap...pull the intake manifold and make sure you don't have a bad gasket and getting good seal....if still running bad then check for clogged cats and if needed get some cheap new ones...pm me and I'll shoot you a link for high flow cats for $35 each....they're crap but they work. if still no bueno then I'd be talking to a tuner.
Your front o2 sensors could be part of the problems as well but I'd think you'd get a code on those already. Try unplugging one of those and see if they tuned those out too. It'd be retarded if he did...but who knows!
Sounds to me like a vacum leak + clogged cats from a bad tune.
My recommendation....replace all vacuum lines (w/heater hose...cheap and easy), replace spark plugs. If still running like crap...pull the intake manifold and make sure you don't have a bad gasket and getting good seal....if still running bad then check for clogged cats and if needed get some cheap new ones...pm me and I'll shoot you a link for high flow cats for $35 each....they're crap but they work. if still no bueno then I'd be talking to a tuner.
Your front o2 sensors could be part of the problems as well but I'd think you'd get a code on those already. Try unplugging one of those and see if they tuned those out too. It'd be retarded if he did...but who knows!
#44
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Okay so the car got an entire list of parts. I put in new AcDelco plugs, msd wires, pcv valve, fuel filter, removed and cleaned tb, fixed the one collapsed vacuum line, installed new bank 1 & 2 sensor 1 oxygen sensors, flushed out the dex cool for fresh coolant, and swapped out the flowmaster cb for a magnaflow. I removed the battery and cleaned up the terminals, and removed the pcm to clean out some corrosion that I found (made a post about that here: https://ls1tech.com/forums/pcm-diagn...cs-inside.html). After all that, I got one code set for one of the new o2 sensors having a low voltage. I'm swapping that out under it's warranty (Delphi). Of all this I'm not sure what fixed the issue but it seems to run so much better now. It's doensn't show any of the symptoms I was having before however it still feels as if though it has a slight mifire at idle but I think worn out motor mounts are making me paranoid. Sorry I couldn't narrow this down to one particular part but I had all this stuff just sitting in the garage so just installed all of it. I'll update this thread if the problem comes back.