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Misfire while idling and low rpms

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Old 11-07-2005, 03:50 PM
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Default Misfire while idling and low rpms

My check engine light started flashing the other night while I was cruising in 6th gear. Went to Autozone and they let me scan it, came up with a Random Misfire code. The light flashed a couple more times on my way home.
I took my car to my mechanic and he hooked a scanner up to it. The scanner showed a lot of misfires on cylinder #5 and some on #4 but it only misfires at an idle or if you're driving at low rpms, like under 2000.
We changed the plug and wire on #5 and also swapped the coil pack and it's still misfiring.
Any ideas??? The only thing I've done to my car recently was clean the air filter(K&N).
Old 11-07-2005, 04:35 PM
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I have the same problem that Ive been unable to solve for 6 months...more cylinders...fouled 3 sets of plugs...replaced everything (coils, O2s, wires, plugs, etc)...down to ohming injectors and new wire harness now.
Let me know if you solve it.
Old 11-07-2005, 04:58 PM
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DONT DRIVE YOUR CAR.... with the ses light flashing you are doing serious damage to your cats and o2's the falshing light is to get your attention and is a serious thing not like the normal steady ses light. I would take your car to a shop that does smog/diag and tell them what you have had on and when.
Old 11-07-2005, 05:56 PM
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Check your MAF. If you doused your K&N with oil after cleaning it.... some oil might have found it's way onto the MAF elements. This can cause all kinds of probs. Since that's all you've done to the car recently....I'd check this first. If the MAF has some oil or debris on it, carefully cleaning the elements with rubbing alcohol and a Q-tip might help solve your problem. Same for the IAT sensor that's attached to the airlid.
Old 11-07-2005, 07:30 PM
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Originally Posted by Sylvrls1Z
DONT DRIVE YOUR CAR.... with the ses light flashing you are doing serious damage to your cats and o2's the falshing light is to get your attention and is a serious thing not like the normal steady ses light. I would take your car to a shop that does smog/diag and tell them what you have had on and when.
Cats are gutted so I'm not too worried about damaging them. However you also said it hurts the O2's, that's something I am concerned about
Old 11-07-2005, 07:30 PM
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Originally Posted by Schantin
Check your MAF. If you doused your K&N with oil after cleaning it.... some oil might have found it's way onto the MAF elements. This can cause all kinds of probs. Since that's all you've done to the car recently....I'd check this first. If the MAF has some oil or debris on it, carefully cleaning the elements with rubbing alcohol and a Q-tip might help solve your problem. Same for the IAT sensor that's attached to the airlid.
Ok, I'll try that. Thanks
Old 11-08-2005, 06:46 AM
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cats? what are they?...but the problem comes and goes in mine...it will run fine for a few hundred miles...then its like flipping a switch.

Car was running perfect but the plugs were real black from this on/off misfire problem so I figured I would change them...fire it up and the car runs like a champ for 20 miles...then right back to where I started...misfires and carrying on.

I think it is electrical...wiring harness...ground...
Old 11-08-2005, 07:29 AM
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You guys should run additional grounds from the computer to the chassis. I think you are on the right track.
Old 11-08-2005, 09:17 AM
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i have the same problem.had it already for about 6 months also.they checked plugs,coil packs.i am tired of this issue,the gas mileage is very poor.eveytime i turn the car on on a cold start it dies and it takes awhile for it to idle.the tuning seems right or so they told me at the tunning was fine,tunning was done by dynotex in san antonio texas.took it back to the tunning shop and they changed plugs and wires and checked for more stuff but they couldnt figure it out.the SES is steady on and sometimes when its a cold start the SES will start flashing.i also have massive loss of power and i mean excessive.i scanned the problem several times,and all the times it says misfire in multiple cylinders.please experts chime in,this little problem its getting expensive and annoying.
Old 11-09-2005, 09:28 AM
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I forgot to mention that the car doesn't feel like it's misfiring. It idles smooth and doesn't run rough at all



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