Should I replace TB?
Thread Starter
Drifting
Joined: Aug 2002
Posts: 1,857
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From: Yakima WA
Should I replace TB?
problem is; my TB doesn't always fully retract and thus idle is high at 1000 RPM's at idle, in nuetral. Sometimes it is fine and if I gun it, in park, it will go back to normal. I have tried "simple" cleaning of TB by spraying TB w/cleaner to no avail.
Question is: Do I need to completely remove and clean TB or replace? Is there an easy fix? I have limited tools and experience. If I do replace TB, should I order a new 52 MM from MID America? suggestions welcome
Question is: Do I need to completely remove and clean TB or replace? Is there an easy fix? I have limited tools and experience. If I do replace TB, should I order a new 52 MM from MID America? suggestions welcome
Team Owner
Joined: Sep 2001
Posts: 62,137
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Re: Should I replace TB? (dbwade36)
Take it out and clean it thoroughly, take apart the IAC and clean that, reset the TPS voltage, and you should be fine.
No need for a new one if it works fine once you clean it. Definitely no need for a bigger one.
No need for a new one if it works fine once you clean it. Definitely no need for a bigger one.
Pro
Joined: Jul 2002
Posts: 729
Likes: 4
From: Yukon OK
Re: Should I replace TB? (vader86)
Take it out and clean it thoroughly, take apart the IAC and clean that, reset the TPS voltage, and you should be fine.
No need for a new one if it works fine once you clean it. Definitely no need for a bigger one.
No need for a new one if it works fine once you clean it. Definitely no need for a bigger one.
Are you sure the TB is not closing all the way?? Open the hood when the idle is high and push on the linkage to close the throttle. Does that affect the idle? Does not sound like a TB problem. Other areas to check: leaking vacuum line, leak around the intake / plenum / runners.
Melting Slicks
Joined: Jun 2002
Posts: 2,168
Likes: 16
From: Phoenix AZ
Re: Should I replace TB? (dbwade36)
With the motor off, try moving the throttle body shaft up and down, back and forth. There shouldn't be much play at all in it. There will be some slight play, even in a good TB if you push/pull the shaft side-to-side. If there is excessive play moving it up and down, forward and back, the bushings are shot and that will cause the TB to stick partially open when the engine is running and theTB is under vacuum, even if it closes normally with the motor off.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: Should I replace TB? (vetracer)
I didn't even think the tb had bushings. I think the throttle plate shaft just rides against the aluminum bore.
I'd be looking at the iac and for vacuum leaks before assuming the tb needs replacing.
There's an idle set screw on the drivers side that sets how far the plates shut. They should never shut all the way, or they'll bind in the tb bore. Basically, they should always be leaking past somewhat.
BTW, i love your sig!
I'd be looking at the iac and for vacuum leaks before assuming the tb needs replacing.
There's an idle set screw on the drivers side that sets how far the plates shut. They should never shut all the way, or they'll bind in the tb bore. Basically, they should always be leaking past somewhat.
BTW, i love your sig!
Instructor
Joined: Jun 2003
Posts: 128
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From: tampa fl
Re: Should I replace TB? (dbwade36)
If you look I had the same problem 2 weeks ago. I took and recleaned the TB and I noticed some build up right where the shaft for the plates goes into the TB hit it with cleaner and Liquid Wrench let it soak in and tried it out a few times by hand and now everything is fine, strange how just this litle bit of carbon can cause the trouble it did. Hope this helps!
ROCKY85 :hurray:
ROCKY85 :hurray:
