idle problems after intake install
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idle problems after intake install last night and tongiht i removed the intake manifold to replace the knock sensors and also had to replace the oil pressure sending unit bc i broke it when i pulled the manifold off. i have everything back on the car, everything plugged up (as far as i know) and went to crank the car, the idle is high, WAY high, like 3000 rpms. what the heck could be causing this?
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Do you disconnect the throttle cable from the throttle body when removing? Could the throttle cable not be seated right, causing the throttle plate to partially open? As far as the sensors, I dunno. I guess you could reset the PCM and see if everything works out after the relearn procedure.
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nah the TB is closed all the way, i even disconnected the cable to make sure it was closed so no air was gettin in.
to reset the pcm.....turn key to accessory, pull the ignition and pcm fuses, tuen key to off position after 5 minutes, replace fuses, and start her up, correct?
to reset the pcm.....turn key to accessory, pull the ignition and pcm fuses, tuen key to off position after 5 minutes, replace fuses, and start her up, correct?
MY guess is you have a vaccum leak. RE-CHECK that ALL hoses are connected, if everything is on....maybe a gasket may not have sealed. Thats all i could think of.
Last edited by sprayin'99ss; Feb 10, 2007 at 11:35 PM.
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everything is on im pretty sure off, ive triple checked it....but if i had a vacuum leak wouldnt this cause the car to idle lower than normal and want to cut off?
Originally Posted by kyles2000z
everything is on im pretty sure off, ive triple checked it....but if i had a vacuum leak wouldnt this cause the car to idle lower than normal and want to cut off?
Nope, Its a vacuum leak for sure. make sure the brake booster hose is all the way on, on both sides, if you have egr still on, make sure it is sealed correctly, if all else fails remove the intake and MAKE SURE it seats flush on the heads then torque using the sequence.
the un metered air causes the engine to rev high
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A vacuum leak would make the car want to choke and die, because it's getting far more unmetered air and it's not giving enough fuel to compensate. If your car doesn't have a rough choppy idle, I wouldn't suspect a vacuum leak.
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Originally Posted by sprayin'99ss
MY guess is you have a vaccum leak. RE-CHECK that ALL hoses are connected, if everything is on....maybe a gasket may not have sealed. Thats all i could think of.
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ok so where should i start on finding this air leak and how should i go about it? the vaccum hoses look to be ok. the 5 vaccum hoses that i could find seem to be ok.
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the vaccum hose to the brake booster is working, its attached to the booster on one end and the back on the intake on the other end. the 2 hoses on the driver side over the valve cover, they are on tight, as well as the opposite end of those hoses. small vaccum hose runnin to backside on intake from passenger is on tight. pcv is on tight....am i overlooking somethin? this is starting to **** me off!
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car is way too loud to hear any hissing sound lol. as far as intake port gaskets....there arent any gaskets underneath the intake to the port....it's metal to platic as far as i know.
Originally Posted by kyles2000z
there arent any gaskets underneath the intake to the port....it's metal to platic as far as i know.
Theres your problem, lol. There is supposed to be a round rubber gasket for each port, if you dont have em then theres your vacuum leak. Youre gonna have to pull the manifold again.
Originally Posted by kyles2000z
car is way too loud to hear any hissing sound lol. as far as intake port gaskets....there arent any gaskets underneath the intake to the port....it's metal to platic as far as i know.
Oh man that sucks....that would be the prob.
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put it this way, however i pulled the manifold off, is how it sits right now. i didnt analyze it but i didnt notice any gaskets underneath when i pulled it off. an its not like i have 8 gaskets layin around in my garage and in the engine bay that wouldve fallin off in the process of remvoing it. however the intake came off is how it sits now.
the crunk it up again today and the car will idle at 3400 for about 2-3 weconds, then fall down and sputter and start loping like its gotta a big camin it, kidna like the plugs are bad i guess and you gotta give it gas to keep it running. it'll die on it own if y dont give it gas ocne the rpms start to fall.
the crunk it up again today and the car will idle at 3400 for about 2-3 weconds, then fall down and sputter and start loping like its gotta a big camin it, kidna like the plugs are bad i guess and you gotta give it gas to keep it running. it'll die on it own if y dont give it gas ocne the rpms start to fall.
Originally Posted by kyles2000z
put it this way, however i pulled the manifold off, is how it sits right now. i didnt analyze it but i didnt notice any gaskets underneath when i pulled it off. an its not like i have 8 gaskets layin around in my garage and in the engine bay that wouldve fallin off in the process of remvoing it. however the intake came off is how it sits now.
the crunk it up again today and the car will idle at 3400 for about 2-3 weconds, then fall down and sputter and start loping like its gotta a big camin it, kidna like the plugs are bad i guess and you gotta give it gas to keep it running. it'll die on it own if y dont give it gas ocne the rpms start to fall.
the crunk it up again today and the car will idle at 3400 for about 2-3 weconds, then fall down and sputter and start loping like its gotta a big camin it, kidna like the plugs are bad i guess and you gotta give it gas to keep it running. it'll die on it own if y dont give it gas ocne the rpms start to fall.