How to open Tps switch
#16
Under the Lift
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It appears your return spring is weak or somebody may have had it off and not preloaded it when reinstalled. The spring could be wound another turn on the throttle shaft.
#17
Race Car
Thread Starter
There are 3-springs the lighter one toward the inside f the shaft seems not very tight, I did not remove that one. Should I remove it requires taking out the shaft and add one more turn? What correlation do all the springs have as far as tension, is each spring related to Gas, Cruse and plate?
#18
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I have cleaned it, just very little tension sometimes it will not go to the fully closed position. Off the car it closes very little resistance but add a little pull form any of the throttle cables and it does not close consistently. This would explain some odd running issues. I'm not sure what to do at this point!
Did you adjust the TPS per the shop manual? If adjusted incorrectly it can actually hold the throttle plate open slightly requiring more force to consistantly close the throttle plate completely...which sounds similar to how I read what you are saying.
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#19
Race Car
Thread Starter
Took the intake off and it seems like the T-plate is not closing completely, is this normal. I will check the Tps switch and see if its hanging it open but this is what I found. I see an idle adjustment nut and screw on the bottom but have not touched that. I had to turn my larger adjustment screw in 5-turns to get the idle down at all. This was cleaned and now I see a residue on the plate I wonder why, I only ran it for a short time. Picture of the Tps is before I cleaned it.
#20
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Dang...
Throttle plates typically never close "completely" if you get them "too closed" the plate will start to stick/jam on the throttle body. I think there is a spec in the Shop Manuals for the S4s, I assume there is (or should be) also one for the Euro. --- EDIT: Checked and couldn't find it.
BTW, I have a solution for all of that oil in your intake/Throttle Body/TPS switch.. see www.sharkvent.com
Yes, shameless plug, but pics like this are one of the many reasons I made the product.
Throttle plates typically never close "completely" if you get them "too closed" the plate will start to stick/jam on the throttle body. I think there is a spec in the Shop Manuals for the S4s, I assume there is (or should be) also one for the Euro. --- EDIT: Checked and couldn't find it.
BTW, I have a solution for all of that oil in your intake/Throttle Body/TPS switch.. see www.sharkvent.com
Yes, shameless plug, but pics like this are one of the many reasons I made the product.
Last edited by DR; 03-20-2009 at 08:21 PM.
#21
Race Car
Thread Starter
Dr I think your on target with the Tps I just relieved the pressure from the tps and the plate sealed. I will now check the wot, idle switch is clicking maybe some progress. I guess it does not take much opening to increase the idle.
#22
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#23
Sure, it's easier to replace it, but for all you DIY'ers like me, there is a seam around the circumference. Saw along that with a hacksaw, but not all the way through to the inside. There are some tabs along this seam. Best not to saw into them but gently pry them away from the case a little with a very small flat-blade screwdriver. You will hear the glue separate. Pry along the seam gap you created with the hacksaw and the rest of the glue should gradually give up its hold. The connector will stay with the base half - don't saw that. Anyway, with a little patience the case will separate in such a way that a lip on the base inside the seam stays largely intact so it can be reassembled very securely with fresh glue.
OK; I placed the switch face down, resting between the jaws of a table vice, suspended so that each metal tab of the housing lay on a vice jaw, and the switch was suspended in between the vice jaws. Tabs on the bottom half of the housing were facing upwards, and it seemed that some good taps on them, would drive the bottom half of the housing downwards and separate from the top half of the housing. Indeed, I took a hammer and punch and tapped the tabs in round robin fashion and the bottom half of the housing was cleanly driven downwards and separated.
How does that oily film get inside the housing, I wonder? (A bit more search revealed that worn throttle pivot bushings are the culprit. Not sure if I'm ready for a TB dis-assembly.)
Last edited by mj1pate; 06-13-2010 at 02:02 AM.
#24
Now, I'm just curious....is there a way to seal the body of the switch where the throttle plate pivot passes through, so that no oil penetrates into the switch case? Seems unlikely but just wondering.
#25
in close examination, there isn't much oil in the switch.... a light film in some areas. the WOT failure is the same that many others have reported. The WOT switch arm is fatigued. If the axis of the switch can rotate more, then WOT continuity is made. But that much rotation is out of range of the throttle movement.