TPS/Throttle Body problem.

[eder-loco]

So i just got this new Rebuilt Throttle Body, Bored out to 63mm but flows like a 65mm with the Shaved butterfly option. along with the FIAV blockoff plate, coolant lines still hooked up.(even do not used) and both sensors hooked up as well.
i put it on the car, set the tps to 0% at idle with dsmlink, and 100% at WOT.
when the car is turned on, the butterfly seems to get a bit stuck, so i have to give it an extra inch of force to get it open. Nothing big. But it does get a bit stuck, but when the car is off, it feels just normal.
Anybody had anything similar?

it sucks because when im at a light about to go. i over rev my damn car due to the butterfly getting stuck a bit.

 

[boostnhard]

Thats damn weird, may be TPS gets stuck when it gets powered. Try swapping it with a friends

 

[anteversion]

Sounds like your butterfly plate is too tight in the TB bore, so when it comes in the fully closed position, the plate get stuck in the bore. Maybe your machine shop did it a bit to tight

 

[romeen]

First, make sure that the throttle cable isn't binding on anything. With the car warmed up disconnect the cable from the throttle lever/pulley and try opening the plate to see if it gets stuck. If it does then you may need to loosen the screws that hold the throttle plate to the shaft and slightly reposition the plate for better clearance from the bore of the TB. If you do end up having to do this be careful not to strip the screws (use proper sized screwdriver) and then use red loctite when resecuring the screws.

 

[eder-loco]

Any ideas why it might only happen while the car is on?

 

[romeen]

My guess would be heat/thermal expansion of certain parts causing something to bind. Does it do it if the car is on but not yet warmed up?

 

[eder-loco]

yea, even when i have just started the car.

 

[romeen]

yea, even when i have just started the car.

That is strange, but then again we're talking about a DSM so anything can happen!

Go ahead and do what I suggested in post #4. If it sticks when you turn the throttle lever by hand with cable unattached then it has to be from the throttle lever, plate, shaft seals, etc. If it sticks when you depress the gas pedal with cable unattached then it has to be from the cable, cruise control, pedal assembly, etc.

I'm still leaning towards the throttle plate not being centered in the throttle bore correctly.

 

[DSMunknown]

eder-loco - Please fill out your profile completely.

I support Romeen's thoughts on the subject. Either the plate is not centered/aligned correctly or the springs are not wound properly. If you don't mind me asking, who rebuilt the TB?

Just out of curiosity, have you done a BLT with the new TB installed?

 

[turbodsm18]

Asumming its a 1g throttle body, on the back of the throttle body, Check the throttle stop screw....There should be a little pin at the tip that should move about 1mm ....... Make sure that pin is not stuck, if it is working then adjust the throttle stop screw to hold the throttle plate open just a tad more(like a 1/4 turn).... This will raise the idle a tad so you will have to compensate for it somehow....

I will almost bet that its your throttle stop screw and Steve Monroe probably built the throttle body...

 

[eder-loco]

That is strange, but then again we're talking about a DSM so anything can happen!

Go ahead and do what I suggested in post #4. If it sticks when you turn the throttle lever by hand with cable unattached then it has to be from the throttle lever, plate, shaft seals, etc. If it sticks when you depress the gas pedal with cable unattached then it has to be from the cable, cruise control, pedal assembly, etc.

I'm still leaning towards the throttle plate not being centered in the throttle bore correctly.

i took off the cable and moved the throttle lever by hand, doesn't get stuck feels just normal.
i went inside the car and pressed on the pedal while the car was off and same. feels normal.
As far as where the TB came from, I will ask the shop that i got it from. its a very reputable shop. so i know they good for their word.
Also have not done a BLT yet, But i did notice my boost went up. and a/f ratios went off due to the fact that the old Seals on the old TB were leaking Pretty bad at just 8psi while doing a BLT.

 

[eder-loco]

Asumming its a 1g throttle body, on the back of the throttle body, Check the throttle stop screw....There should be a little pin at the tip that should move about 1mm ....... Make sure that pin is not stuck, if it is working then adjust the throttle stop screw to hold the throttle plate open just a tad more(like a 1/4 turn).... This will raise the idle a tad so you will have to compensate for it somehow....

I will almost bet that its your throttle stop screw and Steve Monroe probably built the throttle body...

i see no movement in the back, Nor found the little pin. Is there a picture diagram that shows the pin ## talking about?

 

[Auto RS T]

The pin Turbodsm18 is referring to is the 1g throttle closed switch. He was saying you can adjust it out so the throttle doesn't have the ability to close all the way and get stuck. Doing this will effect your idle however.

I would take Romeen's advice and loosen up the throttle plate screws and re-adjust the plate either up or down a tad. The plate and shaft always slide a little back and forth so that is normal.

If re-adjusting the plate doesn't work I would be curious to know if the bore was correct to the plate size. A caliper could be used for these measurements.

 

[stevemonroe]

Just ran acrosss this thread and wanted to add some info;
I may or may not have supplied this TB to the shop where eder-loco purchased it but the only reason that a throttle blade is sticking with the motor running but not sticking with the motor off is because motor vacuum is pulling the throttle blade beyond the normal closed position. I can't duplicate every condition on the workbench that might be encountered in the heat of an engine bay but I've learned over the years that what works on 97.5% of these cars isn't right on the rest.
Anyway, the only adjustment I'd suggest making is to widen the blade gap slightly by turning in the CTS. If that won't get 'er done, send the TB back to me and I'll take care of it and even refund for the postage.
Thanks
Steve

 

[ummdsmwhat]

had the same prob. it was just too tight.