p0300 misfire code help
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Joined: Jan 2003
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From: Bay area, Ca
p0300 misfire code help well as the title says i got a p0300 engine misfire code. i pulled plugs 1,3,5,7 and i think they look alright. i took pics that can be seen in my sig. please adivce to what i should look at next after i check the remaining plugs.
thanks
thanks
Thread Starter
TECH Regular
Joined: Jan 2003
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From: Bay area, Ca
actually my freind was driving the other day and he did rev it pass redline. and even told him to shift cuzz he was past 6000-6100rpm. did you see the plugs? how do they look?is there a distinct sound when you have bent pushrod? i have had the car on since then but it sounds normal. it idles real rough and the car starts to shake occasionally while im trying to scan.
i hope its not a bent pushrod
thanks
TTT
i hope its not a bent pushrod
thanks
TTT
Nothing wrong with 6000-6100. I believe he means a miss shift such as going from 3rd to 2nd instead of 4th at wot, which would put your rpm's well over 7000.
Check your plugs and wires, clear the code and see if it comes back.
Check your plugs and wires, clear the code and see if it comes back.
Thread Starter
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Joined: Jan 2003
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From: Bay area, Ca
Originally Posted by SmokingWS6
Nothing wrong with 6000-6100. I believe he means a miss shift such as going from 3rd to 2nd instead of 4th at wot, which would put your rpm's well over 7000.
Check your plugs and wires, clear the code and see if it comes back.
Check your plugs and wires, clear the code and see if it comes back.
alright the rpms didnt go past 7k. it did past 6100 though. i got the driver side check next ill check pass. side. driver side looked fine.
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Verdad Gallardo Thread Starter
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Joined: Jan 2003
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From: Bay area, Ca
alright i checked plugs 1,2,3,5,7 and all look good. i hooked up the scanner (atap)and showed that all cylinders are misfiring. everytime i rev up the engine the misfire counts increase. what should i look at next.?
thanks
thanks
More importantly how does it run? Any lack in performance or does it feel fine? Try using a different gas station next time you fill up.
If everything mechanically checks out, motor runs good ect i'd look into disabling your missfire counts or raising the limits. Methods on how to do it can be found in the pcm tuning sticky.
If everything mechanically checks out, motor runs good ect i'd look into disabling your missfire counts or raising the limits. Methods on how to do it can be found in the pcm tuning sticky.
Thread Starter
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havent ran it since the code come on. when the code came on it was running real rough and no throttle response. so i parked it. after a couple of days i scanned with atap. i logged 3 seperate times and out of the 3 times 1 didnt havent any problems then the other two it idled rough for a few seconds a couple of times.
what are all the coils connected to0?ecu?ckps?
what are all the coils connected to0?ecu?ckps?
I had that code before my updated mods every now and then. The past weekend I added heads, ls6 intake, ported TB, PCV conversion, MSD wires, plugs, and new pushrods as well. Ran it this week and got the code again. My car runs fine and when I dynoed it with just the cam and LT's I got 350 rwhp. I've been told its a bogus code sometimes and guys just delete it.
Originally Posted by Eiyse98ls1
another log and the idle pretty bad the whole time. i recognized that the ftlt bank 1 was at 25% and -9-10% on bank 2 this is at idle
Thread Starter
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From: Bay area, Ca
premium gas it is. and plugs i have pulled and look good. hopefully a freind that works at dealer can piont me in the right direction. he cleard the code and it came back as we were driving . car ran good for 2-3 miles then gave a hestitation and started running bad and code agian. would not have no response then half a mile later back to normal
check to be sure you are getting good spark on all cyls. Something is randomly causing all cyls to not fire. P0300 is harder to trace because it's usually random and in all cyls not a specific bank or cyl.
What do your o2 readings look like (high or low millivolts)? LTFT and STFT's high or low?
Last time I had a p0300 code, it was a loose connection on the main harness that fed all the coils.
What do your o2 readings look like (high or low millivolts)? LTFT and STFT's high or low?
Last time I had a p0300 code, it was a loose connection on the main harness that fed all the coils.
Originally Posted by SmokingWS6
could be a sign of a bad o2, or perhaps a stuck or static injector. Something is happening on the drivers side of the motor that is causing big problems. Time to pull all the plugs and see how they look.
Thread Starter
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From: Bay area, Ca
if the o2's were bad wouldnt it set a code for bad o2's and not the random engine misfire? a freind of mine the works for chevy said i can be my front o2's or fuel injector problem. y would these set the random engine misfire code?
thanks
thanks
