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p0300 MIL code

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Old Apr 22, 2010 | 01:28 PM
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kSStamp09's Avatar
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Default p0300 MIL code

If anyone can help me with this it would be blessing lol. I got this code the other day, have no idea how long its been on. But I had 2 other codes for the O2 heaters so both upstreams are brand new and downs are tuned out (no cats, kooks lt's). This code was present then, but now its back an it is the only code. Car idles seemingly well but has power loss and the misfire becomes very relivent around 2k. It has progressivly gotten worst after the new o2/ air filter change, yet it is an intermitten problem.
It is an ls6 swaped crate motor with less than 10k miles, with asa cam. I've cleaned the maf, replaced the filter with a fram, checked both the ckp and cmp sensors, both working fine. Tried to do a ckp relearn but never could get it to complete. Smoke tested for vacuum leaks, nothing. I plan to look for an exhaust leak tonight or leaking o2. Would that cause it?
I also plan to check computer wiring to the coils. Open for any suggestions and thanks in advance!
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Old Apr 23, 2010 | 05:35 AM
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From: on the dyno tuning in MD
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First thing I would do is log misfires and find which cylinder it is missing on... then check the plug and wire - possibly the plug got dropped or something and is cracked...

Was the car tuned for the cam?
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Old Apr 23, 2010 | 10:03 AM
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Originally Posted by BLK02WS6
First thing I would do is log misfires and find which cylinder it is missing on... then check the plug and wire - possibly the plug got dropped or something and is cracked...

Was the car tuned for the cam?

Yes it was tuned, and I did log it and it came up with misfires on every cylinder ranging from 700 to 11,00 with an average of 5k on each cylinder. I checked the injectors last night an got 10.6 ohms on all but one (11.2 on it) which is out of the 11-14 ohm specs. so I'm pretty confident its the injectors. I guess I got a batch of very bad gas. Also tested the voltage at the injector connection an had a solid 11.8 at startup.
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