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Discussion Starter #1
Rough idle and service engine soon light flashing, 5 minutes after starting. Shut it off start it back up runs smooth for 5 minutes then back to the trouble. Disconnected the battery for 15 minutes, reconnected iit, started it runs fine for 5 minutes, then back to the trouble. DTC is p0300. Please help? Thank you in advance.
 

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Check your fuel pump pressure. Does it run good at higher speed? If so then a possible vac leak. Check engine vacuum at idle. Could also be a fuel injector issue.
Any other codes?
 

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if check engine light is flashing then dont start engine and run it for any length of time , flashing check engine it s a warning of engine failure
that code means you have multiple misfires
 

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Discussion Starter #4
Yes the service engine light is flashing, any idea what could be the cause? I will have the entire list of DTC's it is throwing out soon. Will post a reply when i get the all
 

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Discussion Starter #7
Also, i have installed new injection spider, new fuel pump, fuel filter, plugs wires cap and rotor, and the coil, ignition control module, CKP sensor, cam sensor, TPS, knock sensor, and the PCM(which is guaranteed to be plug and play). Also replaced all O2 sensors.
 

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Discussion Starter #10
Check your fuel pump pressure. Does it run good at higher speed? If so then a possible vac leak. Check engine vacuum at idle. Could also be a fuel injector issue.
Any other codes?
It runs the same at idle or any speed. Replaced fuel pump and injector assembly with engine swap.
 

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Discussion Starter #13
Ok, now see this is why i love this forum. Anyway, the shop that figured out and fixed my cranks but doesnt start due to no spark(reluctor ring) that shop said they did the crank relearn on it, but i am not positive they even had the proper equipment to do the relearn. You say "relearns" does that mean more than just the crank relearn has to be performed? Also where should i take it to get this/these done, i have exhausted almost all my resources at this point. Cant afford to throw good money after bad money, e.g., just paid $400 for this shop to tell me the misfire "might" be the fuel injection spider, and want $600 to replace it to see "if" that was indeed the issue.
 

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You need a scan tool to do relearns the crank sensor is one of them ,not sure of all of them but I'm certain there is more than just crank, maybe someone here can tell us
 

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just an idea here , take out front o2 sensor and start it up , see if it runs better, if it does then you know clogged cat is your problem, if not , you just ruled it out
 

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The crank reluctor is what sets the timing. The crank and the cam are connected together with the timing belt, if the timing belt was correctly installed, or not touched, the cam will be fine when the crank gets reset.
The relearn procedure just resets the info from the crank reluctor to the PCM, so the engine spark and fuel will be properly timed.
I believe there is a YouTube procedure for the relearn.

The P0300 is a random mis-fire {some or all cylinders}, to have a mis-fire unique to cylinder 3, the code would be P0303.
 
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