throttle body to big?

Bad92GT

The 5 Minute Plan Man

Jun 10, 2004

492

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SC

May 10, 2006

#1

• May 10, 2006

• #1

Mods in signature.. my car, for maybe 10 mins after you start it up when its dead cold, the car had a hesitation in it.. once it warms up it helps but its fairly bad when its cold.. therefore i have to let it sit and warm up before i can take it for a spin because controlling the throttle is a pita with the hesitation.. i was thinking it could be the throttle body considering it might be sucking in to much air or the air can't come in fast enough.. if its not what could cause the hesitation? i tap the gas and it makes the loud sound of it sucking in the air through the TB and then stumbles up to 1k and drops back to 700 at idle.. then it will be a little bit better but if it sits for maybe a minute afterwards it starts all over again.. its not that bad.. just a pita.. ideas opinions suggestions?

 

Grn92LX

Fidanza Man!

Founding Member

Jan 14, 2001

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New York

May 10, 2006

#2

• May 10, 2006

• #2

That has nothing to do with the tb. A 70mm tb isn't big, anyway.

Thats a lean issue.

 

Bad92GT

The 5 Minute Plan Man

Jun 10, 2004

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May 10, 2006

#3

• May 10, 2006

• #3

i run 38 PSI on my FPR.. go up i suppose?

 

RaceDvr50

New Member

Jul 26, 2005

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Coon Rapids

May 10, 2006

#4

• May 10, 2006

• #4

Ok well this could be a little of both but the throttle body shouldn't affect idle because it should be closed at idle and the IAC should be controlling your idle. You could try removing and cleaning the passages behind your IAC and maybe trying a different IAC. Also the EGR could cause a problem like this if it had a serious problem. It shouldn't even open at idle but if it got stuck partway open it could be causing a problem. First two places to look anyway. Also a throttle body that is too big can cause a slight hesitation in my experience but not those idle problems.

 

RaceDvr50

New Member

Jul 26, 2005

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Coon Rapids

May 10, 2006

#5

• May 10, 2006

• #5

Whoops, 24# injectors? Ford claims that they won't atomize properly below 40psi., try about 42. Also did you set the voltage on your TPS after you installed the throttle body? That can cause a loping idle or worse.

 

Zero_chance

Founding Member

May 29, 2001

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Maricopa, AZ

May 10, 2006

#6

• May 10, 2006

• #6

Another vote for cleaning the IAC out.

 

DMAN302

My mom says thanks for the pearl necklace.

Nov 8, 2003

2,120

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windsor, Canada

May 10, 2006

#7

• May 10, 2006

• #7

I have also heard issues with the fuel pattern and 24 pound injectors under 40 PSI...just a thought.

 

D

Daggar

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Jul 19, 2004

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May 10, 2006

#8

• May 10, 2006

• #8

Fuel pressure, IAC, and TPS are all great places to look. My only other suggestion off the top of my head, might be to check and ensure there are no Vac leaks. Even a small one can cause the symptoms you describe.

As always, check for codes. It occurs to me that an 02 sensor while in open loop, that reads too lean (you'd get a code for being rich) might also cause these kinds of symptoms.