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Discussion Starter · #1 ·
Hello Everyone,

I recently removed my Cats and am now having a problem where the car is pulling without my foot on the accelerator and idling high i cant tell you exact rpm but its probably around 11 to 1200 rpms to the point where if i put it from park to drive it slams into gear
(ouch)
check as a coincidence no vacuum leaks
scanned with snap on scan tool ran KOER (key on engine running) test and came back with a P0121 - Throttle Position (TP) Circuit Performance Problem shop tested and said was working properly by monitoring its volt in another screen when stepping on gas pedal only thing we seen was the o2 sensors were tacked out a 1000mv ? there plugged in any ideas Please help.

in order to park my car i have to turn on (a) Defroster on max to drop idle or (b) max A/c

The car is sct tuned
with mils off and rear o2's Off tune one
rear o2s off tune 2
base tune -tune 4


Please Advise
Thanks in advance..
John
 

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adjust your idle dude. my car did the same thing just adjust your idle screw till its about 750-850 like normal
 

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don't touch this idle screw !
you might have a trouble with your IAC valve or you have a vaccum leak.
do you hear a hissing sound near your throttle body or intake manifold ?

don't forget, don't touch the idle screw on your tb !
 

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Discussion Starter · #4 ·
i don't believe there to be any leaks as i spend almost 20 $ in spraying the entire engine down with carburetor cleaner didn't raise the idle at all


only thing i have found is the following....
my o2 sensors are pegged at 1000mv im thinking when he welded the exhaust back together since he put the ground on the exhaust he may have shorted out one or two of my o2 sensors but i do not know if that should effect the idle at all.

Also I've found in my scan tool my case ground is not grounded if anyone could help on possibly locating where that maybe so i can fix it it would be greatly Appreciated

also its trowing a tp out of preformance soft code but when tested appears ok


thanks in advance

John
 

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ur o2 sensors shouldnt have a effect like that. they will effect but not int hat harsh of a manner
 

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Discussion Starter · #8 ·
they only check the tps sensor to the extend of checking its readings thur the scanner volt reading from closed to wot witch he said it was reading fine...

as far as intake we did a leak down test and it did fine
 
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