Throttle body sticky

[Hubnut]

My throttle body it really sticky when I first push the accelerator. In fact, sometimes it's stuck so hard that I have to really punch the accelerator to unstick it. I noticed in the throat of the throttle body that those round disks that cover it are closing too much and that's where it's sticking. Can I simply adjust that with a screw or something? And if so, will that affect timing or idle or other stuff? Thanks!

 

[Hubnut]

Sorry. It's a 91 350ci with TBI.

 

[k20]

its actually the tb sticking and not the cable or pedal? If it always does it at a particular time (maybe after it sits overnight or whatever) pop the hood and try to move the linkage on the tb to make sure. If it is the throttle stop isnt adjustable that I know of, will probably make it run all kinds of weird with the fuel injection. Also check and make sure the bushings on the throttle shaft arent worn, letting the shaft wiggle and jam.

 

[4X4HIGH]

Sounds like a wore out throttle shaft and or TBI unit. You can have the TBI bushed to fix this problem. You will have to take the TBI unit COMPLETELY apart to have this done and most carb rebuild shops can do it. I have a friend here who does them and has been doing them for 75.00 and then you just need to reassemble the TBI unit.

My 454 TBI unit was like this before i had him bush it for me, now it moves smooth as silk.

 

[Hubnut]

I'll try to photgraph it tomorrow. Sure looks like the little round disks close too tightly and get stuck.

 

[eagle mark]

This happens often when the throttle shaft wears and then the buterflys close so tight they stick. Yes it needs rebuilt but if you drill out the plug covering the adjustment screw you can turn it in a little to relive the problem...

 

[Hubnut]

Is that on the right (driver's side) front of the tb? There is a screw there visible. That part of the tb has a small piece cracked off (right up to that flathead screw head). How much for a new throttle body?

 

[eagle mark]

Is that on the right (driver's side) front of the tb? There is a screw there visible. That part of the tb has a small piece cracked off (right up to that flathead screw head). How much for a new throttle body?

That's where it's at but should be a Torx in there? Not sure of a new price but there are rebuilds out there available...

 

[4X4HIGH]

You cannot simply "adjust" the base idle screw since the idle setting is controlled by the IAC motor and also a setting within the chip burn.

 

[George_Pimpdaddy]

definitely sounds like bad bushings on the shaft I know this as playing with mine today I noticed mine was doing it too

 

[eagle mark]

You cannot simply "adjust" the base idle screw since the idle setting is controlled by the IAC motor and also a setting within the chip burn.

The "minimum air setting" has to let a certain amount of air through the plates. If it's not enough they stick, like this one. It still does not change the idle until you let so much air in the IAC count goes to 0. You can make this adjustment without worry. But if you were really concerned about how the ECM is handling the adjustment look at the IAC count at full warm up at idle and it should be somewhere betwwen 20 and 50.

 

[4X4HIGH]

I guess i should have been more specific in saying that "adjusting" the minimum air setting WILL NOT increase idle RPM's, that is controlled by the IAC motor and also a setting within a chip burn. If the TBI unit is wore out and the thottle blades are sticking it "might" fix that scenerio.