Need culprit of cod P0300/ideas???
Thread Starter
TECH Enthusiast
Joined: Oct 2002
Posts: 739
Likes: 0
From: houston,texas
Need culprit of cod P0300/ideas??? I am asking for a cousin that has a 2002 Firehawk..his exhaust mods are as follows: MACS w/ORYP...Borla exhaust,Hollley powershot,descreened MAF,LS6 intake....Well he recently has been getting a code P0300 random misfire according to autozone and it throws the SES light..it flashes on and off and it goes away....but it only happens after the car is warmed up and he restarts it...EX. he goes to the store,for 10 to 15 min..and whenever he comes back and starts the SES flashes and then goes away...his car also bogs down when it flashes occasionally.......so his car doesn't throw the light at cold start ups....He thought it could have been plugs and wires so he changed them with no luck...it still kept doing this after the car has been warmed up and restarted....he rechecked the plugs and wires and made sure everything was snug and right....but still does it.....Does anybody have any idea???? 
...Could it be an injector?....any ideas thanx in advance!! 
...Could it be an injector?....any ideas thanx in advance!! 
On The Tree
Joined: Jun 2003
Posts: 113
Likes: 0
Re: Need culprit of cod P0300/ideas??? I'd say check the fuel pressure. After that, I'd say check the connectors at the PCM and the connectors to the coils. The PCM controls the coils directly on the LS1s (no ignition control module in between), so if it's an ignition related misfire, I'd suspect the PCM (unless some or all of the coils went bad at the same time.....stranger things have happened though).
Launching!
Joined: Apr 2003
Posts: 272
Likes: 0
From: Cincinnati, Ohio
Re: Need culprit of cod P0300/ideas??? Well, the fact that it only happens when warm would steer me in the electrical malfunction direction. I would probably be suspect of a coil breaking down.
Re: Need culprit of cod P0300/ideas??? He may want to check his 02 sensors. When the car is cold its starts in open loop and when it warms up it goes into closed loop. sounds maybe like an 02 sensor problem. I dont know how but maybe they are lose or something
Re: Need culprit of cod P0300/ideas??? Just a stab in the dark...
http://www.seattleautomotive.com/ckpdoc.htm
http://www.seattleautomotive.com/ckpdoc.htm
Thread Starter
TECH Enthusiast
Joined: Oct 2002
Posts: 739
Likes: 0
From: houston,texas
Re: Need culprit of cod P0300/ideas???
It seemed to be cylinder #2, so jpz28 and his cousin are going to switch coil packs, and we are going to see if the misfire follows the coil.
