Question on high idle after mods
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Question on high idle after mods
Yesterday and today, I installed the FAST manifold and a Nick Williams 90 throttle body. Everything went pretty smooth. Cut the **** out of my arms though. What was GM thinking when they put those clips in the cowl? Anyway, started the car and the idle just went from 2000 to 3000. Drove the car to the gas station to get gas and it's idleing still at 3000 to 3500. Come to a stop and it stays there. So I come home and adjust the idle screw all the way out, no change. I pull the throttle wire off and the throttle closes another, oh, 1/4". So I start adjusting the bracket holding the throttle cable. I finally get it to where if your going down the road and push in on the clutch, it idles at 2000, come to a dead stop and it drops to 1000 to 1100. So,I got to thinking if it could be a vacum leak and the only place where I can think a vacum leak could be would be on the map sensor in the back of the manifold. Everything else is on there the way it's supposed to be. The reason I say the map sensor is it just sticks in a hole back there kinda flopping around in the hole. Is this supposed to be this way? That's the way it was on the old manifold also. Could this be the problem or is there something else I need to be looking for?
Oh and I forgot to add, I pulled all of the air crap off also. I do have the SES light on right now, I just haven't had time to look at the codes, but I assume that is due to the air not being attached. I'm going to have the car tuned, hopefully this week or next week so if it is the air codes, they can do away with those codes, right? But this wouldn't have anything to do with this high idle issue would it?
Oh and I forgot to add, I pulled all of the air crap off also. I do have the SES light on right now, I just haven't had time to look at the codes, but I assume that is due to the air not being attached. I'm going to have the car tuned, hopefully this week or next week so if it is the air codes, they can do away with those codes, right? But this wouldn't have anything to do with this high idle issue would it?
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The AIR wouldn't affect the idle. I thought the idle was PCM controlled though? What screw were you adjusting? It might be all fudged up due to the larger throttle body, the intake shouldn't have anything to do with it. I just chimed in to let you know AIR won't do it.
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Originally Posted by LoudmouthLT1
The AIR wouldn't affect the idle. I thought the idle was PCM controlled though? What screw were you adjusting? It might be all fudged up due to the larger throttle body, the intake shouldn't have anything to do with it. I just chimed in to let you know AIR won't do it.
THanks
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I just went out and got the codes that are causing the SES light,
PO121 Throttle Position Sensor Performance
PO410 Air System
PO412 Air Solenoid Relay Control Circuit.
I expected the PO410 and PO412, but what causes the PO121?
PO121 Throttle Position Sensor Performance
PO410 Air System
PO412 Air Solenoid Relay Control Circuit.
I expected the PO410 and PO412, but what causes the PO121?
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Did you install the o-ring around the IAC motor on the new TB? Either that or you have a vacuum leak somewhere. I have heard of people leaving the washers stuck to the bottom of the intake after removing the bolts that FAST ships them with. They sometimes stick to the bottom after you remove the bolts to install the intake.
Or you have the throttle cable in the wrong hole. What year is your car and what hole are you using?
Check you PM's
Nick
Or you have the throttle cable in the wrong hole. What year is your car and what hole are you using?
Check you PM's
Nick
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Originally Posted by Nick Williams
Did you install the o-ring around the IAC motor on the new TB? Either that or you have a vacuum leak somewhere. I have heard of people leaving the washers stuck to the bottom of the intake after removing the bolts that FAST ships them with. They sometimes stick to the bottom after you remove the bolts to install the intake.
Or you have the throttle cable in the wrong hole. What year is your car and what hole are you using?
Check you PM's
Nick
Or you have the throttle cable in the wrong hole. What year is your car and what hole are you using?
Check you PM's
Nick
Bill Estes
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Nick, I think you were right, I did adjust the cable and it did bring the idle down. However, still when your going down the road and you push in on the clutch, you begin idleing at 2000 rpm it will come down to about 1800 rpm until you come to a dead stop and then it drops to 1000 rpm. It did this ever since I put the cam in the car. Its just agravating as hell that when you let off the gas your idle won't drop to where it's suppose to be. I've seen a lot of this on this board and nobody seems to be able to fix it, at least not from what I've seen.
Originally Posted by Nick Williams
I think that his throttle cable needed to be adjusted. It was holding it open a little.
Nick
Nick
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Originally Posted by Ragtop 99
What TPS % does your car read when the TB is closed. Make sure you do not need to reset the TPS position.
How do you reset the TPS position?
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I am having the EXACT same problem, although I have the FAST 90mm TB. I can't figure it out either. Maybe we can work this out together. It's so embarassing to come to a light looking like John Force.
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Originally Posted by DramaFoYoMama
I am having the EXACT same problem, although I have the FAST 90mm TB. I can't figure it out either. Maybe we can work this out together. It's so embarassing to come to a light looking like John Force.
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Originally Posted by Blue Falcon
If you have some form of tuning software, have you checked the Idle Air in Gear?
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Originally Posted by SS125
Boy do I know how that feels. Do you think Nick could chime in on this? Or really anybody.
Do you have a scan tool?
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Are the tps screws adjustable? turning tps may adjust parameters that pcm sees tps is at. A vacuum leak would make to car run horrible, lack of acceleration and bad idle.
also you would hear to vacuum leak. Also check throttle cable binding.
also you would hear to vacuum leak. Also check throttle cable binding.
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Originally Posted by Nick Williams
Bill
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Originally Posted by PAULZ98SS
Are the tps screws adjustable? turning tps may adjust parameters that pcm sees tps is at. A vacuum leak would make to car run horrible, lack of acceleration and bad idle.
also you would hear to vacuum leak. Also check throttle cable binding.
also you would hear to vacuum leak. Also check throttle cable binding.