General Maintenance & Repairs - My LS1 camaro is always at 1500 RPM

Hey.. I hav an LS1 camaro and when its idleing its always revved at 1500 RPM.. does anyone kno why it could be like this?

Vacuum Leak?

Throttle blade adjustment way out of wack

whats a throttle blade?

look at your idle speed adjustment on the throttlebody

whats a throttle blade?

if u look at the throttle body inside there is a blae that opens and closes allowing more air in hence allowing the engijne to get air and run. if the blade is stuck open slightly it will allow more air in then normal at idle and will rev higher, my guess is vacuum leak or tune issue, someone may have set the idle too high, is anything done to the car?

Check what the guy's above said first, and if it isn't that then it may be your idle air control valve bad on the side of your throttle body and if that isn't it some carb cleaner and while car is running spray around intake to see if intake gaskets are leaking. There is a vacume line on the back of the intake and see if it and pcv and any othe lines in the intake are leaking. Hope you figure out whats the matter. GOOD LUCK

if i had to put money on it. its a vacuum leak

I changed my plugs the other day and now whenever i and cruising around and come to a stop, it idles around 1500 for 10sec or so and slowly drops down to a regular idle. I may have unplugged something by accident.

Sounds like IAC valve is starting to go bad, try swapping one from another vehicle if you know anyone else that has an LS1

Sounds like IAC valve is starting to go bad, try swapping one from another vehicle if you know anyone else that has an LS1

Tried the swap, still does it. Soon as I press the clutch in sits at about 1500rpms for about 10s and drops down to 900. Not sure what to look for now.

Check the tps sensor on your car, I had a similar issue and it turned out to be a oily tps sensor...I have no idea how oil got in it..

Check the tps sensor on your car, I had a similar issue and it turned out to be a oily tps sensor...I have no idea how oil got in it..

cool ty i'll check it out.

Did you figure it out ?

I have the same problem. I have added clamps to all vacuum lines that did not have any, replaced the IAC, cleaned the air filter, did the IAC reset steps, and it still idles and fluctuates between 1500-1000rpm. I discovered a hose running from the drivers side front fender along the fender and over the brake power booster and then it just stops hanging there. I just got the car so I dont have any idea where it should go. Does anyone know???? Could this be the problem or part of it?

I think its a vacuum leak because when i push the brake it effects the idle.

tomorrow I plan on buying carb spray
spraying the intake and vacuum lines for leaks
checking the TB for leaks
EGR is not there capped off by the headers
check the PVC
Clean the TB
after that I dont know what else. any suggestions?

This is my first LS1 so I dont know much, mostly I know old school cars from the 70's back.

This car has
after market comp
headers
after market cam
stall 2800
ls6 intake

The black hose on the drivers side that is just hanging over the power booster is blowning air, pretty strongly. where does this go? why would it just be hanging there?

Figured out the the black hose blowing air, disconnected that. while troubleshooting:
spraying the intake and vacuum lines for leaks
checking the TB for leaks
EGR is not there capped off by the headers
check the PVC (replaced)
Clean the TB

I discovered the butterfly in the throttle body had a large hole drilled in it
( 1/4")
everything else checked out okay. some friends came by that know more about this than i do, and we made the iac come all the way out and reinstalled it with it unplugged, and adjusted the idle down. The general thought is this is just a temp. fix as it needs to be tuned properly. we got it to idle at about 900rpm and the cam is not loppy at all.

This car 1998 z28 has the following mods:
comp cam 222/226 .566 .569 112lsa
comp cam valve springs
jet hot sterling coated long tube headers
lanes custom y pipe with flow master collector
3:73 rear end gears
precision ind. vigilante stall 2800
b & m tranny cooler
corvette ls6 intake
free ram air hood mod
slp angled smooth bellow
texas performance high performance lid
slp cold air intake
k & n filter
functional ss hood

supposedly dyno tuned with ls1 edition by chris robinson

something is bad wrong, everyone says it needs to be dyno tuned, but what about the large hole in the throttle body butterfly?

anyone????

sounds like someone drilled into your tb blade with the cam so it wouldnt die on idle, ill have to pull my maf off and measure my hole. but i dont think its 1/4" lol.

my friends car has a 1/8" hole in the throttle butterfly, and I have seen online throttle body butterflies, with and without the hole. but none as large as the hole in mine. On a vette site the say it should not have a hole at all. I have looked everywhere I can not find any good answers.

any help would be appreciated.

still need help pls....

Dude, get a bolt that fits tight with a lock-nut and metal washers and put it in there. If you want to make extra sure it doesn't come loose over time, drill a hole in the end of the bolt so a cotter pin will fit, thats what some carb manufacturers do. Done.

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