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Throttle Body Installation Mistake

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Old 08-31-11, 08:15 PM
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Gate
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Default Throttle Body Installation Mistake

Throttle body cleaned, greased, and put back on. No more idle stalls. Shifting is much smoother. Two problems: Idle in park is at 1.25 and higher rpms required to go any given speed (about .5 to 7.5). I tried tightening, loosening, and centering the tps. Accelerating and idle rpms as well as shifting slightly fluctuate depending on how tightly the tps spring is, but I can't seem to get it perfect.

This thread has recently been condensed, some posts may seem out of context but SexCoupe and Vroomin350 have been very helpful.

Last edited by Gate; 09-02-11 at 03:02 PM.
Old 08-31-11, 10:03 PM
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Vroomin350
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Sounds like a MAF sensor problem... Honestly I don't knoe but what you are describing sounds very familiar to the all well known "honda idle jump" ... In other words, its like you were pressibg the gas pedal and letting go, repeat process... someone should chime in here shortly
Old 09-01-11, 06:03 AM
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mitsuguy
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sc300 or 400?

also, and I don't recall specifically, but there are sensors on the throttle body, and on some cars, that is where the idle air motor lives... these guys don't like water, so there is a possibility one was damaged?
Old 09-01-11, 11:58 AM
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SexCoupe
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put the throttle body back on and start the car back up see if it still does it...if so spray the enginebay with carbcleaner..use it to see if the idle changes and try to find the vacuum leak.. if there isnt one unhook the maf while its running and see what happens...also before you put the throttle body back on check to see if u knocked any sensor plugs off check to see if u accidently unplugged a injector... just cus u took off the throttle body doesnt mean the throttle body is the only thing that "could" be wrong
Old 09-01-11, 12:09 PM
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Vroomin350
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come and let us know once you did the above, i know this must be frsustarting but there is gotta be something wrong.
Old 09-01-11, 03:00 PM
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SexCoupe
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you sound like a chick ranting man chill out and summarize....have you put on a new throttle body gasket??? im assuming no since you ran out of throttle body cleaner and didnt get another bottle and im sure you dont have 2 or 3 gaskets laying around
Old 09-01-11, 03:19 PM
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SexCoupe
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you need a new gasket man/girl they are cheap under 15 bucks....do it!!
Old 09-02-11, 03:03 PM
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Gate
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Originally Posted by SexCoupe
you need a new gasket man/girl they are cheap under 15 bucks....do it!!
A new gasket should definitely make an improvement. For now, I'm trying to fiddle with the tps to get it "just right".
Old 09-03-11, 11:56 AM
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I'm going out to get a new tube that ripped. I think it might be related. Might pick up a new gasket and some circle hose clamps while I'm out.
Old 09-04-11, 02:38 PM
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Just replaced the tube and gasket. Idle in drive and reverse is .8, which I'm fine with for now, but idle in neutral and park is 1.25. There must still be a vacuum leak. Some of the rubber tubes were so old and brittle, I'm sure some were damaged after being handled for the first time in what must be several years. Time for some new clamps and a few more hoses. I'm gonna see this through. Be back later.
Old 10-02-11, 12:27 AM
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Originally Posted by Gate
Just replaced the tube and gasket. Idle in drive and reverse is .8, which I'm fine with for now, but idle in neutral and park is 1.25. There must still be a vacuum leak. Some of the rubber tubes were so old and brittle, I'm sure some were damaged after being handled for the first time in what must be several years. Time for some new clamps and a few more hoses. I'm gonna see this through. Be back later.
Vaccuum lines could very well be the problem, but they usually create a rev up/down repeatedly situation. If it is not doing that, I would keep playing with the TPS. What is the voltage reading from the TPS? Try and find out what it needs to be and compare it to your reading. Rotating forward or backward should change the voltage, and thus, change the RPM's.
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