Need help PLEASE!
Thread Starter
Racer
Joined: Feb 2011
Posts: 310
Likes: 9
From: Miami Florida
Need help PLEASE!
So my has been idling pretty rough and throwing the p0300 code and its supposedly cylinders 1&2. I have changed the 02's, spark plugs 1&2 also changed those spark plugs wires. I also cleaned the maf and throttle body but still doing it. Have no idea what else it can be any help is greatly appreciated and thanks in advance guys
Melting Slicks
Joined: Aug 2005
Posts: 2,960
Likes: 112
From: New Braunfels TX
When I have had trouble finding a misfire the cylinder is running alot lower in temp. Then I start looking at valvetrain etc if I have allready swapped coil packs and the problem doesnt follow the coil pack.
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Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
check the injectors. one or more of them could be clogged up or for some reason not flowing properly
they are ez to pull off and have them flow checked.
also check the coils. you can swap the "bad cyl" coil to another cyl and see if the problem
factory service manual is a MUST. it has some pretty good flowcharts and documentation to help you troubleshoot misfires and the correct steps to follow.
buy or borrow one and good luck tracking down the problem!
they are ez to pull off and have them flow checked.
also check the coils. you can swap the "bad cyl" coil to another cyl and see if the problem
factory service manual is a MUST. it has some pretty good flowcharts and documentation to help you troubleshoot misfires and the correct steps to follow.
buy or borrow one and good luck tracking down the problem!
Melting Slicks
Joined: Aug 2005
Posts: 2,960
Likes: 112
From: New Braunfels TX
Did you look at the valvetrain? Did you inspect the injector? Did you do a leakdown? How about an compression test? You must look at everything very closely. Also rare Ive seen the wiring inside the coil pack harness snap (became brittle). But that is rare one that I know of since 2002.
Last edited by JMBLOWNWS6; Jun 24, 2013 at 07:44 AM.
ISIS SUCKS FAT CHOAD
Joined: Oct 2008
Posts: 8,124
Likes: 53
From: Earth, United States
ISIS SUCKS FAT CHOAD
Joined: Oct 2008
Posts: 8,124
Likes: 53
From: Earth, United States
Well one thing is for certain the problem is somewhere between the valve stem tip and the crankshaft. Anything else is pure speculation. However chances are its a broken valve(s) or a broken ring land(s) either way you can almost rest assured that if its a valve it most definitely made contact with a piston.
If it "runs like a Subaru" that distinct sound is what a 7 or less cylinder LS engine sounds like.
If it "runs like a Subaru" that distinct sound is what a 7 or less cylinder LS engine sounds like.
ISIS SUCKS FAT CHOAD
Joined: Oct 2008
Posts: 8,124
Likes: 53
From: Earth, United States
I'm not saying yours is a valve but you definitely have a loss of compression as your test have indicated so there's probably a broke valve or broke ring land or something.