P0300 please help
#1
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P0300 please help
Over the last 3 weeks my SS sets a P0300 multiple cylinder misfire code at least daily , and sometimes it will set it again after I clear it from the PCM . I really dont know where to look for a problem like that on this car . I took all the plugs out thinking I might see something there , but they all looked pretty good . They all were light tan with a few tiny brown specs on the back of the porcelin . The car seems to be running good , but it feels noticably slower that before , and sometimes it idles kinda lopey like it has a small cam . I was watching my spark advance at idle , and its all over the place ....switching back and fourth like a 02 sensor from like -5 degrees to 12 degrees ....it that normal ? Because the cas seems to running fine , I dont really have any other thing to go off besides the code , and the fact it feels a bit poochier than before . I went racing last night and the best the car would do was a 14.61@97 mph in air as good my 13 sec sig times , and back then I didnt have help of the aluminum flywheel or Borla exhaust .
When I dissconnect the battery , the car seems to have a noticable power increase for about a day . I disconnected it at the strip last night , and every pass after that It went 99 mph , I couldnt get better than 97.1 prior .
I do have clutch chatter witht he new spec and fidendza flywheel , can that noise cause fits with the pcm ?
My ingals torque brace also makes a audible metallic rapping I can hear from inside the car , can that cause fits with the PCM ?
I watched KR when both noises are audible and Im not getting any KR at all . Sorry for all the questions , Im just aggrevated and miffed .
When I dissconnect the battery , the car seems to have a noticable power increase for about a day . I disconnected it at the strip last night , and every pass after that It went 99 mph , I couldnt get better than 97.1 prior .
I do have clutch chatter witht he new spec and fidendza flywheel , can that noise cause fits with the pcm ?
My ingals torque brace also makes a audible metallic rapping I can hear from inside the car , can that cause fits with the PCM ?
I watched KR when both noises are audible and Im not getting any KR at all . Sorry for all the questions , Im just aggrevated and miffed .
Last edited by SilverSS/SC; 05-20-2006 at 11:20 AM.
#2
Premium Member
You need to get someone with a TECH2 to scan your misfire accumulator/counters to determine which specific cylinder/s is acting up. The plugs may look OK but you could still have a cracked porcelin or other plug issues- but that plug usually is a bit darker due to intermittent fouling. Other things known to cause a misfire on the LSJ include a bad crank sensor (usually sets a DTC but not always), bad COP, or sticking valves due to fuel/carbon deposts that cause the valve to "hang up" especially cold.
BUT
Step 1 - determine which cylinder is setting the DTC and go from there
HTH
WOT
BUT
Step 1 - determine which cylinder is setting the DTC and go from there
HTH
WOT
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