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***HELP*** P0300 Code right before Emissions!

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Old Feb 22, 2012 | 10:30 AM
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Default ***HELP*** P0300 Code right before Emissions!

Hey guys, i posted in another thread i found with a seemingly similar issue as the one I've developed recently but it was in the GenIV section and with my need to resolve this issue as quick as possible I wanted to put up another thread in this PCM Diagnostics section to cover my bases.

The car has been parked since the drive home after developing the flashing check engine light other than to drive it across the street to the parts store to read the P0300 code. I quickly checked my wires and they weren't coming into contact with anything (stock wires, too short to touch manifolds but i realize they could be giving way being 10 years old). The car doesnt seem like its falling on its face or anything while the check engine light is blinking.

I came across this thread (https://ls1tech.com/forums/generatio...g-problem.html) in a search and at first it seemed like my Cats would be the culprit as his issue was looking to be. I recently had a true dual system put on my APS twin turbo'd 02 TA (rear O2's programmed out) and had the exhaust fabbed to accept my modified stock Cats (cats had their ends chopped off and V-Band Clamps welded in so that i could easily swap them with race pipes). I'm going to try and remove the cats and run it open dumped to see if the code stops (hopefully later tonight after work) but I'm confused as to why his broken valve spring was causing the issue seeing as how the code disappeared/reappeared with the removal and application of the cats respectively. I'm hoping in my case its the cats and not a broken valve spring. I have emissions coming up next month and I need this fixed fast. Go figure this happens right before i take it in to get tested.

Anyone have any insight into what would cause the code to disappear and resurface like that with the cats going on/off?

If the removal of my cats fixes the problem what should my next step be? I obviously need the cats for emissions but I wont pass with a blinking check engine light.

If removing the cats doesnt fix the issue from what i've gathered it looks like i should check the plugs and then wires next. If it comes to it and i pull the plugs, what exactly should i be looking for? Same with the wires.

Sorry for all of the questions, just kind of in a bind as emissions are creeping up on me fast and i don't want to prolong this ordeal.
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