Misfire Code P0300
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Joined: Jun 2003
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From: UpState NY
Misfire Code P0300
I own a 2000 coupe and decided to have headers, cats, new sparkplug wires, & plugs installed (40K miles). The car worked fine before, now I'm getting a
check engine & misfire code. The garage swears all the engine cylinders are firing they claimed to have hooked it up to a computer. While idling the car RPM's seem to drop real low, while driving you can hear pop & crackle out the exhaust. Any Ideas? If they damaged a O2 sensor could that do it? Any other idea's?
check engine & misfire code. The garage swears all the engine cylinders are firing they claimed to have hooked it up to a computer. While idling the car RPM's seem to drop real low, while driving you can hear pop & crackle out the exhaust. Any Ideas? If they damaged a O2 sensor could that do it? Any other idea's?
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From: Just trying to make it through each day.
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St. Jude Donor '03-'04
Re: Misfire Code P0300 (steveNY)
Common code after headers. Could possibly have a bad wire or plug. Burning a wire after headers is common too. The gurggle and pop (unless really loud like a backfire) is common too. Check those wires!!!!!!
A re-tune isn't a bad idea either to maximixe the mods......air/fuel may need some adjusting.
A re-tune isn't a bad idea either to maximixe the mods......air/fuel may need some adjusting.
Melting Slicks
Joined: Aug 2001
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From: Wichita KS
Re: Misfire Code P0300 (steveNY)
..... damaged a O2 sensor could that do it? ....
Melting Slicks
Joined: Mar 2001
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From: New Milford CT
Re: Misfire Code P0300 (steveNY)
I got that code after heads, cam and headers. At first it was everyday, then it went to every week, then to once a month. Can't explain why, this all happened before any tuning. I made no changes to the car, it just fixed itself.
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From: GARDENA Ca, State Of Konfusion
St. Jude Donor '05
Re: Misfire Code P0300 (steveNY)
Your idle could be too low, after my cam installation I got the misfire code. I had to rasie my out of gear idle to 775 and the in gear idle to 825, all is well.
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Joined: Jun 2003
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From: UpState NY
Re: Misfire Code P0300 (Buckmaster)
Thanks for the help! I will start with having the wires & plugs checked first. My problem is, I don't know of any Corvette specialty shops in upstate NY.
