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changed spark plugs, now hesitates

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Old Nov 22, 2006 | 07:19 PM
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changed spark plugs, now hesitates

so yeah, I changed the plugs and wires, I gapped them at .060, me and dad made sure to tighten them up good, and the wires are definitely in, we heard them "snap" into place. Now it hesitates and you can tell something's wrong with it when I give it more than about 30% throttle. I have a 2000 SS A4 by the way. Any help would be appreciated.
Old Nov 22, 2006 | 07:30 PM
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Originally Posted by JeiceFace
so yeah, I changed the plugs and wires, I gapped them at .060, me and dad made sure to tighten them up good, and the wires are definitely in, we heard them "snap" into place. Now it hesitates and you can tell something's wrong with it when I give it more than about 30% throttle. I have a 2000 SS A4 by the way. Any help would be appreciated.
Are you getting an SES? Did it start hesitating immediately? the test drive right after the tuneup? Or did it develop over time after the tuneup? Check and make sure your wires are also plugged into the coils. When you disconnected them from the plugs you might have yanked them loose from the coil aswell. Just double check your connections and make sure your plugs are tightened and not barely hanging. If that all fails, it is possible that a gap was blown wider than needed.
Old Nov 23, 2006 | 10:24 AM
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Could be a bad plug. Every once in a while a bad new plug gets out.

What kind of plugs did you put in?
Old Nov 24, 2006 | 03:44 PM
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im not sure about the SES light, because mine's been on for about 2 years now because of the clogged cats (ive been meaning to change those), but it started hesitating after we changed the plugs and wires. we know they're in tight, and we know the wires are plugged in correctly. i guess i'll just check each spark plug again. ac delco plugs.

btw, i hate doing plugs in this car. there's NO room to work with.
Old Nov 24, 2006 | 04:01 PM
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Just to be sure - you're aware stock cats are covered if you're less than 80K under the federal emissions warranty? With the light on for years have the codes read anyway - did you damage/forget to reinstall the ECT sensor connector by #1 maybe?
Old Nov 24, 2006 | 08:31 PM
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well, im almost at 100k miles now, but i didnt really think that the cats would be a problem since it ran 100k miles on stock plugs. i plugged everything back in where it belonged (ECT sensor - driver's side front?). I'll just have to get out there and undo them tomorrow one by one and see if any of them are messed up.
Old Nov 25, 2006 | 06:50 PM
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Possibly yanked to hard on one of the plug wires and broke or damaged it. Try changing the wires.
Old Nov 26, 2006 | 12:13 AM
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Originally Posted by JeiceFace
btw, i hate doing plugs in this car. there's NO room to work with.
That's unfortunate, because you need to do it again. .060" gap is too big. LS1's like between .045" and .050" Chances are while replacing the plugs you will find your problem - most likely a wire.
Old Nov 26, 2006 | 11:01 AM
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Originally Posted by Marc 85Z28
That's unfortunate, because you need to do it again. .060" gap is too big. LS1's like between .045" and .050" Chances are while replacing the plugs you will find your problem - most likely a wire.
Not true, Some of the NGK's come pre gapped at .060, not sure which ones my are the iridiums I believe they are pre gapped at .050.
Old Nov 26, 2006 | 12:54 PM
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Well, at Oreilly's they told me .060, so that's what I did. I just found my problem: the ceramic coating on one of my plugs was cracked on both sides. I changed that one, and it drives excellent. I've only got 3 left to check, but I doubt they're bad, seeing as it drives so good. The 3 are the ones in the back on the passenger side, and if I notice any bad changes, I'll check those. I appreciate the help.
Old Nov 26, 2006 | 05:17 PM
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thought it might be them plug wires. Happened to a buddy. Glad you found your problem and got it fixed.
Old Nov 26, 2006 | 05:34 PM
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Originally Posted by A&FLs1
Not true, Some of the NGK's come pre gapped at .060, not sure which ones my are the iridiums I believe they are pre gapped at .050.
Just because they're gapped at .060" out of the box DOES NOT mean it's correct. Again, .060" is too big. I've run into dozens of LS1 Corvettes bought at my dealer where the customer brings the car back for a rough idle. Installing a set of NGK TR55's closed down to .045" always fixes the problem.
Old Nov 26, 2006 | 06:50 PM
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Originally Posted by AL SS590 M6
Could be a bad plug. Every once in a while a bad new plug gets out.
score
Old Nov 26, 2006 | 07:36 PM
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Originally Posted by Marc 85Z28
Just because they're gapped at .060" out of the box DOES NOT mean it's correct. Again, .060" is too big. I've run into dozens of LS1 Corvettes bought at my dealer where the customer brings the car back for a rough idle. Installing a set of NGK TR55's closed down to .045" always fixes the problem.
I believe the plugs with a .060" gap is intended for a FI or No2 set up. Some buy them because they believe the plug is better since its intended for higher horse set up but dont know that there is a difference in the gap or why. Therefore .060" pregapped is not incorrect. Just not intended for all cars.
Old Nov 26, 2006 | 08:01 PM
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just food for thought ! under the hood of my Z28 it says .60 gap for the plugs . my car has a little rough idle , maybe that the problem ? i also have tr55 plugs gaped at .60



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