TB question

[scupking]

I have RPM planets 75mm TB and plenum kit. The only issue I'm having is when you lightly press the accelerator down from a dead stop it takes a little extra force. It gets really annoying when in traffic. Once you press it down just a little it becomes unstuck and feels normal until you let your foot off the gas. It’s kind of hard to explain.

 

[Skud]

Not a mustang, but I have the exact same problem with my focus. It has the stock TB. It seems to only do it after the car has warmed up.. It makes it really hard to drive in slow traffic without jerking the car back and forth..

Riley

 

[CobraRed_96_GT]

buy a different throttle return spring

 

[03ghoststang]

what brand is your TB?

 

[scupking]

what brand is your TB?

I have a C&L Upper Inlet Plenum and a PRO Products 75mm T-body.

 

[BennyBlown2v]

my honda does this - my mustang with professional products 75mm tb doesn't

 

[BurningRubber]

I have a Professional Products 75mm throttle body also, its smoother than butter... aka... better than stock.

Are you 100% positive the cable is attached correctly? PP has a tricky setup.

 

[scupking]

I have a Professional Products 75mm throttle body also, its smoother than butter... aka... better than stock.

Are you 100% positive the cable is attached correctly? PP has a tricky setup.

Thats probably my problem but I don't see any other way to hook my throttle cable up to this TB seeing as its some what different then the stock one. Do you have a pic of yours? When I get home I will post a pick of how I have it.

 

[scupking]

bump

 

[Stangsgrl]

my bf's accufab 75mm tb does that,
but my accufab 70mm doesn't...

 

[BurningRubber]

Thats probably my problem but I don't see any other way to hook my throttle cable up to this TB seeing as its some what different then the stock one. Do you have a pic of yours? When I get home I will post a pick of how I have it.

Let me check and if I find one I will post it up.


Heres the best I got, not too detailed with the throttle cable, but its up in that slip below and just to the right of the return spring, you can kind-of see it.

 

[scupking]

This is how I have mine.

View attachment 389727

 

[hotmustang331]

My car has the same problem. And im thinking that its also causing my VERY light throttle low RPM miss. In the same RPM band if I give it a little more gas, car runs SMOOTH all the way through...but if im very light on it or let off while moving in gear, it misses.
SO I think whats happening is that the TB blad is closed too much and thats causing the sticking (vacuum). the IAC is having to flow alot of air to keep the idle right. And then on top of that for ME, I dont think the EEC KNOWS when my throttle is open that slight amount and isnt supplying the fuel needed.

Thats my guess...ill check into it tomorrow

 

[scupking]

My car has the same problem. And im thinking that its also causing my VERY light throttle low RPM miss. In the same RPM band if I give it a little more gas, car runs SMOOTH all the way through...but if im very light on it or let off while moving in gear, it misses.
SO I think whats happening is that the TB blad is closed too much and thats causing the sticking (vacuum). the IAC is having to flow alot of air to keep the idle right. And then on top of that for ME, I dont think the EEC KNOWS when my throttle is open that slight amount and isnt supplying the fuel needed.

Thats my guess...ill check into it tomorrow

My problem is more like a physical problem with the accelerator/TB. It actually takes force to un stick it from a stop or when ever I let my foot off of the peddle. So what happens is I go to push down on the accelerator but it requires more force then usual to start off. So when it dose un stick my car jumps forward.

 

[Skud]

I can think of two causes:

1) I think this could be solved by adjusting the stop screw inward on the throttle body a *VERY* slight amount. Just enough to solve the issue, but not enough to cause the car to idle higher. This would prevent the throttle body plate from "fully" closing, seating in place and getting "stuck".

2) Heat: I think this may be a combination of #1 and this. As the engine heats up, the plate may have a greater expansion than the housing. When the plate heats up enough, it is fully closing and getting stuck. The solution would be the same as #1. *VERY* slightly adjust the setscrew..

On my focus (sorry, not a mustang but the same idea) my car is fine in the winter at all times and in the summer, until the car warms up. Then I experience the same problem you're having. The gas pedal takes that little bit of extra force and then works fine.

Does your car do it all the time? Check it when the car is cold and see if it starts doing if after it's warmed up.

Thanks!!
Riley

 

[BurningRubber]

That doesnt look set up right. I beleive the head on the end of the throttle cable is supposed to pop in both sides and sit evenly across. It looks a little twisted and at an angle there.

 

[speedfreak98r]

Cut some coils off that bad boy. Looks like they're all bunched up.

 

[Skud]

That doesnt look set up right. I beleive the head on the end of the throttle cable is supposed to pop in both sides and sit evenly across. It looks a little twisted and at an angle there.

Indeed..

 

[hotmustang331]

My problem is more like a physical problem with the accelerator/TB. It actually takes force to un stick it from a stop or when ever I let my foot off of the peddle. So what happens is I go to push down on the accelerator but it requires more force then usual to start off. So when it dose un stick my car jumps forward.

Yes, my car does that too but really only while im moving and in gear and there is more vacuum on the motor....thus sticking the TB blade even more. At idle, it will do it sometimes...and yes it causes a slight buck sometimes.

I was just expanding on what I think my specific problem is, with the missing haha. Im haveing the same problems as you + some extra things that I mentioned.

 

[scupking]

Well today I got in the car and pressed the accelerator down before I started her up and I could push it down with out a problem. So it does sound like it could be a vacuum issue as mentioned a few post up.