Code P0300 after headers, not plugs?

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Jan 14, 2003 | 11:18 PM

Steve'01

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Pro

Joined: Jan 2002

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From: Rancho Cordova CA

Code P0300 after headers, not plugs?

I installed headers Sunday and took it out for some testing afterwards. It was running very strong. I was in a short race with a Trans Am and really jumped on it the line. I bounced off my rev limiter twice. The car threw the code Monday; it is running rough and a bit warm. It also sounds off like running on 7. I used an EFI Live Auto tap but not sure how to interpret the screen to see if it will tell me which cylinder or cylinders are having problems. I replaced the plugs tonight and checked the wires, no problems. I also used a water spray bottle to verify that all cylinders were firing and all tubes were hot.

Do you all think it is a bent push rod?

How can I tell which one?

Should I just replace them all with aftermarket?

As always thanks for all the help my friends.
:confused:

Jan 15, 2003 | 12:36 AM

gojo

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From: Winston Salem NC

Re: Code P0300 after headers, not plugs? (Steve'01)

Check them all. You might have more than one and different degrees of bent. Hard to check all the possibilities otherwise.

Jan 15, 2003 | 03:40 AM

WALLstAL

Race Director

Joined: Aug 1999

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From: GARDENA Ca, State Of Konfusion

St. Jude Donor '05

Re: Code P0300 after headers, not plugs? (Steve'01)

I wouldn't think you bent a pushrod in an A4 if you got good programming. Did you get your shift points adjusted for the 3.90? If not you maybe correct.

Jan 15, 2003 | 03:48 AM

davidmax

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From: paradise valley az. us

Re: Code P0300 after headers, not plugs? (wallstAL)

These stock pushrods are VERY STRONG.Lpe specs stock on the TT 427 C5R .They like to keep a weak link in the chain to avoid over damage and limit liability.Even though I had no warrantty went with adj. Boost I have never come close to bending any component a truly strong motor.I LOVE my C5R.Dave S.
PS I will be swapping to chrome moly for reasons other than strength Dave S.

Jan 15, 2003 | 09:30 PM

CJS

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From: New Milford CT

Re: Code P0300 after headers, not plugs? (Buckmaster)

I have gotten that code a few times after I put in all my mods in sig. So I don't know for sure which mod is causing it. The computer seems to be learning this out and I don't usually get it any more. It just went away.

Jan 16, 2003 | 12:30 AM

Steve'01

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From: Rancho Cordova CA

Re: Code P0300 after headers, not plugs? (CJS)

Checked all of the pushrods tonight, none were bent. Then I started compression tests. I was happy to see 160, 159, 160 then 60, #7. I was too bummed to keep checking the other side. I figure that I will have to pull it this weekend anyways. I put some oil down the plug hole and rechecked and still 60lbs. If I remember correctly that means that the piston and rings are OK. I plan on checking the head gasket and valves Saturday. Trying to keep a positive attitude. Hard to tell the wife I brook my car. :sad: :sad: :sad:

Jan 16, 2003 | 09:58 AM

tabbruzz

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From: Central NJ

Re: Code P0300 after headers, not plugs? (Steve'01)

I was getting the 0300 code after the header as well. I heard this is very common, but my engine was running fine.

Jan 17, 2003 | 12:18 AM

Steve'01

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From: Rancho Cordova CA

Re: Code P0300 after headers, not plugs? (tabbruzz)

Did the leak down test tonight. At first I thought the air was going into the intake, but no such luck. It was coming out of the dipstick and around the holes in the heads where the push rods go through. The piston must not be tore up because I still have some compression and she still runs fair. At first I was very bummed almost sick, but need to look at the way the rest of you have, good reason to beef it up. Oh well, tomorrow I plan my new bottom end. Thanks for the words of encouragement. Too bad I sold that extra car. :sad: