Misfire - HELP running out of ideas
Misfire - HELP running out of ideas #2 and #3 cylinders are misfiring. #2 about 6-60 misfires and #3 about 40-90. #3 misfires much more than #2. All other cylinders only misfire slightly at idle. Car runs strong, and has been doing this for 3 months since H/C/I install. Cam is a 224 duration cam with MTI Stage 2 heads and MTI programing.
I have never felt the misfire while driving, Often get a flashing SES light.
I've done the following: swapped plug wires, plugs, coil packs, O2 sensors, retorqed ls6 intake (it was very loose), swapped injectors, and pulled valve cover and visually inspected pushrod/rockers/springs.
HELP? what do I check next?
Dan 99 TA
I have never felt the misfire while driving, Often get a flashing SES light.
I've done the following: swapped plug wires, plugs, coil packs, O2 sensors, retorqed ls6 intake (it was very loose), swapped injectors, and pulled valve cover and visually inspected pushrod/rockers/springs.
HELP? what do I check next?
Dan 99 TA
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Joined: Sep 2002
Posts: 38
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From: Jensen Beach, FL
Re: Misfire - HELP running out of ideas </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by TAGOES11S:
<strong>#2 and #3 cylinders are misfiring. #2 about 6-60 misfires and #3 about 40-90. #3 misfires much more than #2. All other cylinders only misfire slightly at idle. Car runs strong, and has been doing this for 3 months since H/C/I install. Cam is a 224 duration cam with MTI Stage 2 heads and MTI programing.
I have never felt the misfire while driving, Often get a flashing SES light.
I've done the following: swapped plug wires, plugs, coil packs, O2 sensors, retorqed ls6 intake (it was very loose), swapped injectors, and pulled valve cover and visually inspected pushrod/rockers/springs.
HELP? what do I check next?
Dan 99 TA</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Dan, try this...
It's a Crankshaft Position Variation relearn procedure. It stops false misfires and MIL Lights
http://www.seattleautomotive.com/ckpdoc.htm
<strong>#2 and #3 cylinders are misfiring. #2 about 6-60 misfires and #3 about 40-90. #3 misfires much more than #2. All other cylinders only misfire slightly at idle. Car runs strong, and has been doing this for 3 months since H/C/I install. Cam is a 224 duration cam with MTI Stage 2 heads and MTI programing.
I have never felt the misfire while driving, Often get a flashing SES light.
I've done the following: swapped plug wires, plugs, coil packs, O2 sensors, retorqed ls6 intake (it was very loose), swapped injectors, and pulled valve cover and visually inspected pushrod/rockers/springs.
HELP? what do I check next?
Dan 99 TA</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Dan, try this...
It's a Crankshaft Position Variation relearn procedure. It stops false misfires and MIL Lights
http://www.seattleautomotive.com/ckpdoc.htm
Re: Misfire - HELP running out of ideas Ok, looks like it may be just computer programing. I pulled my computer out and put in a friends with the same MTI programing and it shows NO misfires. Could it be as simple as maybe MTI didn't desentize the misfire diagonostic? I would think if it was actually misfiring the new computer would pick it up right away also right?
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Joined: Nov 2001
Posts: 1,355
Likes: 1
From: Chicago (Elgin), IL
Re: Misfire - HELP running out of ideas Another thing I was going to mention is, are you watching this on AutoTap? If so, those numbers are measured at every 200rpm, so 60 misfires on A-Tap is really 30.
Either way at idle on an H&C engine, having a few by that I mean 1-5 is acceptable if it's on a periodic basis. Not a constant 1-5.
<small>[ September 19, 2002, 10:05 AM: Message edited by: CMNTMXR57 ]</small>
Either way at idle on an H&C engine, having a few by that I mean 1-5 is acceptable if it's on a periodic basis. Not a constant 1-5.
<small>[ September 19, 2002, 10:05 AM: Message edited by: CMNTMXR57 ]</small>
