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Car has a rough idle after it gets warmed up

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Old 08-08-2005 | 03:38 PM
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Default Car has a rough idle after it gets warmed up

I have been noticing that my car has a rough idle after the engine gets warmed up. the idle seems kinda low also like 500-600 rpm. Just let me know if that is normal or not.
Old 08-08-2005 | 03:42 PM
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For a low idle it should be rough. However, you shouldn't have that low of an idle. I'd get it scanned to see where you are actually idling at. Then set the idle to where you want it. Probably around 800rpms if it's not already there. Try adjusting the throttle body set screw and see if that fixes the problem. It's a torx screw right under the throttle cam (the thing the throttle cable hooks to) The screw is what this rests on. Just try letting in a little more air and see if it fixes the problem. Have you done any new mods or did you just buy the car. When did this start.
Old 08-08-2005 | 03:50 PM
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Originally Posted by 777
For a low idle it should be rough. However, you shouldn't have that low of an idle. I'd get it scanned to see where you are actually idling at. Then set the idle to where you want it. Probably around 800rpms if it's not already there. Try adjusting the throttle body set screw and see if that fixes the problem. It's a torx screw right under the throttle cam (the thing the throttle cable hooks to) The screw is what this rests on. Just try letting in a little more air and see if it fixes the problem. Have you done any new mods or did you just buy the car. When did this start.

he is an auto, you are manual (I'm guessing seeing as how you have 4.10s)......autos will idle lower (around 500-600rpm vs. the manual's 800rpm idle).......


don't f*ck with it......if you have not changed a cam or done something major that would REQUIRE increased idle speed then you will only cause yourself trouble trying to fix a nonexistent problem...........

now if you REALLY REALLY think it is rougher than "normal" then you can check around at things like spark plugs (what kind and how many miles do you have), plug wires (again....how many miles), clean the injectors....basic maintenance........
Old 08-08-2005 | 04:28 PM
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Default rough idle

I just bought the car in may, when i first got i think it might have idled higher but was still rough. so i have changed to ngk-tr55 plugs and MSD 8.5 and it seem to help some. The only other thing i have done is put a slp flow-pac on and getting ready to put on LM2, 160 therm, and slp fan switch. I also noticed that when cruising around 55-60 mph and let off the gas it seems to jerk also like the brakes were very slightly applied
Old 08-08-2005 | 04:32 PM
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Forgot it also has 63,9xx miles on it also should i do the normal maintance like trans service and fluid change in the rear end to help it last longer?
Old 08-08-2005 | 04:36 PM
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Originally Posted by STREET GOD
I just bought the car in may, when i first got i think it might have idled higher but was still rough. so i have changed to ngk-tr55 plugs and MSD 8.5 and it seem to help some. The only other thing i have done is put a slp flow-pac on and getting ready to put on LM2, 160 therm, and slp fan switch. I also noticed that when cruising around 55-60 mph and let off the gas it seems to jerk also like the brakes were very slightly applied

sounds to me like normal low rpm idle.........


when you say "jerk", explain more.........


Originally Posted by STREET GOD
Forgot it also has 63,9xx miles on it also should i do the normal maintance like trans service and fluid change in the rear end to help it last longer?

I personally would.......unless you KNOW that the last owner had recently done it, I would change all the fluids, check the brakes (bleed the lines and inspect the pads/rotors), etc......if anything, just to know you are fresh and catch any problems that MIGHT be out there....
Old 08-08-2005 | 04:46 PM
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Default Jerk

When i say jerk like going out of lock up from the TC
Old 08-08-2005 | 04:48 PM
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It has a drop in rpm also like it will go from 1600 to 1300 and this is after i have already let off the gas and i am coasting to slow down
Old 08-08-2005 | 05:14 PM
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it could very well be the TC unlocking..........
Old 08-08-2005 | 05:30 PM
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Default Tc

Originally Posted by 2001CamaroGuy
it could very well be the TC unlocking..........
But is that normal?
Old 08-08-2005 | 05:37 PM
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Originally Posted by STREET GOD
But is that normal?
probubly........you would have to compare back to back with someone else's auto car to know for sure.........
Old 08-08-2005 | 05:42 PM
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Default Hey 2001CamaroGuy

[QUOTE=2001CamaroGuy]he is an auto, you are manual (I'm guessing seeing as how you have 4.10s)......autos will idle lower (around 500-600rpm vs. the manual's 800rpm idle).......

Muchas Gracias - thought something might be wrong with the 550RPM idle on my '02 Z28, A4, 3.23:1. Seemed quite low in comparison to nearly all other LS1s here - although it idles nice and smoothly. Your comment put to rest my potential worry. My hat is off to you for your info!

Best of luck.

Steve
Old 08-08-2005 | 06:02 PM
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I am not sure of all info but if you are just sitting ther as it warmes up and idle consitantly gets worse i would check the coolant temp sensor for the computer.
Old 08-08-2005 | 07:16 PM
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may be you have some dirt on the injectores, have them cleaned out, sometimes even with the filter...dirt gets in there, not like dirt dirt...but like gunk that builds up with that many miles on it, wah kinda gas you running? I only us V-Power and it keeps her purring.
Old 08-09-2005 | 09:27 AM
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Does different gas really make a difference? Or is 93, 93 no matter what?
Old 08-09-2005 | 11:53 AM
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Yeah!!! I had some cheapo 93 gas in mine and was only knockin about 170 mpg then when the tank ran dry i got some V Power gas in there and right now i'm running about 210 per tank, BIG DIFFERENCE!! it's the way the gas if formulated and processed at the refinery that makes a diff. Dont skimp out on the gas!!!
Old 08-09-2005 | 01:54 PM
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hmm...well maybe that's why my car's been running a little funny.
Old 08-09-2005 | 02:39 PM
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what kind were you usin???? Did it even have a brand name like Shell or Chevron or Texaco??
Old 08-09-2005 | 08:20 PM
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v power gas is from shell, there 93 octane gas
Old 08-09-2005 | 08:36 PM
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yup yup!! Hey Stretch, how you like the GMMG sound...annoying when cruizing?



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