Hard start and random misfire (updated with screen shots and VIDEOS)
10-20-2011, 04:49 PM
#1
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Hard start and random misfire (updated with screen shots and VIDEOS) Ok car is a 98 z28 m6 I have a hard time starting it. It will crank over a few times and not start then I crank it some more and it starts or if its warmed up and I kill it but try to start it up right after I shut it off it will start right up. And I also have a random misfire that I can't find this has all been goin on ever since I rebuilt the motor and put it back in the car.
Any help is appreciated
Any help is appreciated
Last edited by 6898camaross; 10-26-2011 at 01:02 AM.
10-24-2011, 09:28 PM
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Ok here are some screen shots from my data logger it showed misfire on cylinder one so I swapped coils with number two and reset my codes and today it just showed p0300 random misfire and p3101 and c3103 which I have no clue what those are
10-24-2011, 10:12 PM
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Check your fuel pressure, but seeing those screen shots it is adding alot of fuel to bank 1.
More than just a misfire worth. Might have something to do with your codes, 2 of them are O2 codes.
More than just a misfire worth. Might have something to do with your codes, 2 of them are O2 codes.
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10-25-2011, 08:27 AM
#10
Most likely you have one or two bad front o2's judging by the fuel trims and the fact that you have codes for o2 sensors. Can you get a live scan on them and see if they are switching? With your LT Fuel trim pegged at 25% I'd say you will see them not switching at all or barley at all. Just don't get the Bosch o2's, go with the Denso's from Amazon or RockAuto
Actually, looking at your last pic it is pretty obvious you have a failing o2. See how your fuel trims are very high 23%-25% for bank 1 only? And your bank 2 is in normal specs at around 2-3%? Means you have an issue with bank 1
Actually, looking at your last pic it is pretty obvious you have a failing o2. See how your fuel trims are very high 23%-25% for bank 1 only? And your bank 2 is in normal specs at around 2-3%? Means you have an issue with bank 1
10-25-2011, 05:58 PM
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Most likely you have one or two bad front o2's judging by the fuel trims and the fact that you have codes for o2 sensors. Can you get a live scan on them and see if they are switching? With your LT Fuel trim pegged at 25% I'd say you will see them not switching at all or barley at all. Just don't get the Bosch o2's, go with the Denso's from Amazon or RockAuto
Actually, looking at your last pic it is pretty obvious you have a failing o2. See how your fuel trims are very high 23%-25% for bank 1 only? And your bank 2 is in normal specs at around 2-3%? Means you have an issue with bank 1
Actually, looking at your last pic it is pretty obvious you have a failing o2. See how your fuel trims are very high 23%-25% for bank 1 only? And your bank 2 is in normal specs at around 2-3%? Means you have an issue with bank 1
10-26-2011, 12:11 AM
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Get the O2 issue dealt with first. A bad o2 driving it that rich can cause problems.
It can idle like crap, but cause a dead constant misfire thru the RPM range unlikely.
It sounds like you have a random misfire that was there before this fuel trim issue though?
It can idle like crap, but cause a dead constant misfire thru the RPM range unlikely.
It sounds like you have a random misfire that was there before this fuel trim issue though?
10-26-2011, 12:18 AM
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I think it started at the same time I'm replacing the o2 sensor I just ordered it so.
10-26-2011, 12:52 AM
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Ok here are videos of the data logging
http://youtu.be/SkoBUz0UE9E
http://youtu.be/nR5HHZlNve0
http://youtu.be/ztJoQt34ZKo
http://youtu.be/qZS2PBEjSSg
http://youtu.be/_67ZuacFjXo
http://youtu.be/SkoBUz0UE9E
http://youtu.be/nR5HHZlNve0
http://youtu.be/ztJoQt34ZKo
http://youtu.be/qZS2PBEjSSg
http://youtu.be/_67ZuacFjXo
