rough idle?? what to do
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From: NJ
rough idle?? what to do i just did a tune up last week with msd 8.5mm wires, and ngk t55 plugs gapped .055, now i got a very rough idle i can see misfires on my auto tap jumpin round between cylinders im not throwing any codes though still. should i just go back to the plugs i had before denso iridiums.
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well when i hook up the autotap and i 1st start the car it is smooth with 0 misfires for about 1 min then as it gets warm u see them poping up here and there but in diffrent cylinders, and u can feel it get rough and shake more and more the hotter it gets. they are all firing but just there are misfires, kinda that idle were itll feel good then stumble then idle then stumble not to wear its gonna stall or nuttin but it gets rough, i can only see the plugs being the problem. i also did a fuel filter and a pcv valve but i dont think they would cause that or brand new msd wires
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nope didnt touch em except pullin the old wires off and poping new ones on, could the plugs not being tight enough cause misfires, usually i just snug them by feel but i never had aluminum heads before, and i just used the torque wrench and torqued em to 13ftlbs like the box or spark plugs said for aluminum heads, maybe it wasnt enough perhaps, or could they loosein up from heating and and cooling a few times, ill have to try re tightening them and see if theres any diffrnce
The first set of MSD's I had were faulty and did the same thing. They would not go on and snap like the factory wires do. If this is how yours feel then they are probably faulty as well. Take them off, send them back, and get a new set. They will replace them for free more then likely.
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From: NJ
well they are a tight squeeze u really gotto stretch them to make them stay in place but they did snap into place with that little click ur suposed to hear so i dunnoi think they need to manufacture them with 1/2 in longer wires
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Verdad Gallardo Thread Starter
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From: NJ
nope all stock nuttins been touched all i did was do a tune up and boom shakey idle, its gotto be the plugs i wouldnt think not reuseing the sheilds would cause a problem right? i just sat in it again and it seems idle i get 1 or 2 misfires in almost all cylinders every couple seconds but it jumps around not alwsys the same one, then if i bring the idle up to 1k rpm's it eliminates 95% then at 1300 100% no misfires for the 1.5 minutes i held it there. i dunno if this mean a damn thing to anyone lol
Last edited by rgaynor85; Feb 9, 2006 at 12:14 PM.
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From: south of H-ToWn Tx.
WOW iam haveing the same problem after my spark plug /wire change... Ive checked for lose plugs and wires(changed to 2nd set of wires) everything is on tight(ngk/AC wire's)MY auto tap is showin me it only misfires only at idle ,jumps around to diffrent CYL. but no SES.......But theres no misfire when iam driven 
I think my car dosent like ngk or its something to do with fuel
I think my car dosent like ngk or its something to do with fuel Thread Starter
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From: NJ
wow is right exactly the same, hmm u have the tr55 plugs also? its gotto be our cars dont like the plugs or its somethin to do with the "high performance" wires, i dounno if it'd be the fuel on my part i was havein issues with fuel before it was causeing alot of ping and i switched to sunoco and now its gone so i dunno if it was that good to rid me of the ping i dought it would cause misfire. i wonder why its only at idle for us hmm.....
well im gonna try replacing the plugs with some declo iridium or the denso's that were in there ill keep u posted so maybe u can fix your to we dont need 2 stumbling ls1's hehe
well im gonna try replacing the plugs with some declo iridium or the denso's that were in there ill keep u posted so maybe u can fix your to we dont need 2 stumbling ls1's hehe
On The Tree
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From: south of H-ToWn Tx.
Yes ,There tr55, and yes i am pulling them out in two weeks going with AC or denso iridiums. With my fuel ,it may be my fuel injectors but havent look in to it yet. I say it my plugs.PLZ let me know what you find out 
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From: NJ
well me i ran seafoam thru the gas to clean the injectors,so i dought its the gas and i dought it is for you sense u said it was rough after the tune up, i had the densos in there when i changed emm and they ran good all perfect colored also just so u know, im debateing witch to swtich to i know the densos ran good so im leaning towards them but im curious about the delcos sense they are factory
Looks like im number 3. Ive been having the same problem since i changed my plugs about a month ago. Car idles fine at startup but i start getting misfires after a couple minutes which increase as the car heats up. Im also running tr55 plugs but im still using stock wires. Please let me know if you guys solve the problem.