PLEASE HELP! DESPERATE!

[Paul Higg]

Is it even possible to reinstall the throttle position sensor?

I removed the throttle body for cleaning and stupidly removed the sensor. It seems as if it has some sort of spring pre-load in it. When I reinstall it no matter what position the butterfly flaps are in it does not "catch" on the TPS's little "ears" in it. This is freaking me out.

Also, I just drained a little fluid from the radiator to remove the TB for cleaning and when I started refilling it I noticed a small drip under the car directly under the TB but there are no leaks under it. I used new gaskets and I can see it is dry, the whole area around the TB is dry. I think it might be the water pump. But it is so cramped in there that even with a mirror I cannot see. All I see is a green drip from a piece of metal under the car. I crawled under there with a light and mirror and cannot see where it is leaking. I cannot see anything from the top because it is so cramped. This is really starting to get me down.

Paul

94 LT1

 

[ecss]

Nothing special about the TPS installation.

Is Item #12 in the diagram in place?

1) With throttle valve in the closed position, install the TP sensor to the throttle body assembly, making sure TP sensor lever lines up with the TP sensor driver lever on the throttle shaft.
2) TP sensor attaching screws
3) Tighten 18 inch lbs.
4) Install electrical connector

You're also suppose to use a Tech 1 so the Electronic Brake and Traction Control Module can learn the TP sensor idle position voltage. This is necessary to ensure effective engine torque reduction during Acceleration Slip regulator events.

Most people don't do this step and don't report any problems.

 

[Paul Higg]

Thanks eccs,

Yes, item 12 is in place, you mean the orange foam donut?

I did all you said but I still have the service engine soon light and the ABS light on. I think what happened was the throttle body "tab" that sticks out of the TB is supposed to catch on some spring loaded "ears" in the sensor. Well, I cannot get it to catch. When I start it it is very rough running and those lights. I have no idea how to rewind that spring in the TPS and connect it back up. I am really puzzled.

When I took it apart I could feel the spring unwind in the TPS. What should I do now?

 

[ecss]

The Service Engine Soon and ABS or was it ASR lights are on because the TP sensor voltage is out of range. That should clear when you get the TP sensor back on properly.

You shouldn't have to wind up the spring inside the TP sensor to install it. The spring action is just so the TP sensor follows the movement of the lever of the throttle body.

I can only guess something in the TP sensor broke.

Take the old TP sensor with you to the auto parts store and compare it with a new one.

 

[Paul Higg]

Thanks eccs. I'll do that.

Now what about that coolant leak?

All I did was drain enough coolant to remove and clean the TB. As soon as I started filling it with new coolant I saw a leak on the floor. I know it isn't coming from the TB because there is no fluid below it. I am praying it is not a water pump (91500 miles). The only problem is actually SEEING where it is coming from. It is VERY cramped in the engine. I cannot see from below with a mirror nor above with a mirror. This is very frustrating to say the least. Any ideas on how to trouble shoot it?

 

[ecss]

If it wasn't leaking before you did the throttle body removal it's probably just spilled fluid from the throttle body.

If you go to an Autozone, rent their radiator pressure tester. Put some money down and when you return the tester they refund the money.

You attach a special radiator cap to the fill tank, use the hand pump to pressurize the system to around 16 lbs. and watch the gauge. If you have a leak the gauge pressure will drop. With the system pressurized you can start looking for the leak.

 

[Paul Higg]

Thanks! Great idea!

 

[ecss]

This is a pic. of the back side of the TP sensor.
If you were to use a flat blade screwdriver you should be able to rotate the sensor in one direction and feel the spring tension trying to rotate it back to the home position.

Also if water is dripping from the water pump weep hole, you need to place a rag below the water pump so no water gets on the opti spark which is right below the bottom of the water pump.

 

[Paul Higg]

That's exactly what I feel when I use a screwdriver. The problem is that when I put it in place and move the throttle cable I cannot feel it hitting it and feel no tension as I do when I use the screwdriver. So my question is, how do I install it so that the throttle body tab will engage the spring in the TPS?

As for the water pump. I looked and I am still getting a tiny drop on the floor. I had very small puddle this morning. Only problem is even with a mirror I cannot see the bottom of the water pump because it is so tight there. I tried to reach in there and feel it but I cannot feel much as it is again so tight.

Thanks eccs.

Paul

 

[Paul Higg]

Eccs, I think the leak has stopped, I am crossing my fingers.

Here is what I did. I had my wife sit in the car as I had the Service Engine Soon and Service ASR lights on. So I had the TPS plugged in and while it was running I used a flat blade screwdriver and slowly rotated the sensor. I could hear the engine going to closed loop and the Service Engine Soon light even went out. The ARS light never went out. Is the ASR related to the TPS? I haven't yet had time to research it in the FSM.

Thanks.

Paul

 

[ecss]

The object is to get the lever from the throttle body to "engage" the TP sensor so when the throttle body moves, the TP sensor follows.

So after you get the two in the proper position you rotate the TP sensor until the mounting bolt holes line up. That process at the same time will wind the spring up a little so it puts some back tension agains the arm from the throttle body.

You can tell if the sensor is attached properly by using a volt meter.

With the TP sensor electrical connector plugged in you use two sewing pins or something sharp and pierce the insulation of the Black wire and Blue wire.

Connect the meter Black probe to the sewing pin at the Black wire.
Connect the meter Red probe to the sewing pin at the Blue Wire.

The Black wire is ground.
The Blue wire is the output signal to the PCM.

With the ignition on, throttle body closed, you should measure around .6 volt's DC

When you manually operate the throttle body linkage to wide open throttle, the voltage will steadily increase to a maximum of 4.6 - 5 volts DC.

If the voltage doesn't change when you operate the throttle body linkage, the TP sensor is not being moved by the throttle body linkage arm.

Yes the ASR module monitors the idle position voltage output of the TP sensor. Since the TP sensor has moved from it's original position the ASR module needs to re-learn the voltage out put of the TP sensor at idle. You use a Tech 1 to do that. I'd concentrate on getting the TP sensor installed first.

 

[Paul Higg]

That's EXACTLY the problem, I cannot get it to engage. The TPS sensor is not being moved by the throttle arm. Is there a problem with the TPS? I have NO idea how to install it correctly as the TPS wants to spring back all the time.

 

[ecss]

Don't you just have two choices on which side the arm from the throttle body engages the TP sensor?

 

[Paul Higg]

Yes, that is exactly what I see. But the spring inside the TPS has it wound all the way to one position. So when I place it in the TB and move the throttle it does nothing. I remember when I removed it, the TPS seemed to "unwind". When I install it now it just sits there. It seems as if the TB tab has nothing to bite on to.

I am looking in the FSM now and the Service Engine Light and the Service ASR is all directly related to the TPS. This is driving me crazy because there seems to be no way for the TB tab to move the little wings inside the TPS. Does that sound like a bad TPS? It can only go on one way.

BTW, I really appreciate your help eccs.

 

[G Winter]

So after you get the two in the proper position you rotate the TP sensor until the mounting bolt holes line up. That process at the same time will wind the spring up a little so it puts some back tension agains the arm from the throttle body.

I think what ecss is saying here is that you have to slip the TPS onto the shaft rotated far enough so it engages on the proper side of the tab, then turn it to line up the screws. You may have to have it rotated over 1/4 turn, and be sure you start from the right direction.

Glenn

 

[Paul Higg]

I tried and tried and was so frustrated that I called Gordon Killebrew and spent $10.00 per minute and he told me the only way to replace one is to cut the pipe a little on the throttle body to be even with the TPS. You will still have room to clamp the tubing. He said he went out and actually did it on one of his school cars.

So I did and I actually got it to install but because I was messing with and messing with it I broke it. So now I have a new one on order from Eckler's. I will have to wait till next week. And true to the FSM it is having real rough shifting, high RPM's, and it is running in HIGH idle. I looked at the wiring diagrams and sure enough, the EBTCM, the ASR, all of it is directly related to that stupid little TPS.

My advice. If you ever have to remove the TB for cleaning, NEVER remove the TPS.

I have a feeling that when I receive the new adjustable one from Eckler's (it comes with a neat harness so you can set the voltage just right) everything will be okay. I checked the fuse in the engine and it is not blown so I will just have to wait till next week till I get it.

 

[Hib Halverson]

I tried and tried and was so frustrated that I called Gordon Killebrew and spent $10.00 per minute and he told me t
(snip)
My advice. If you ever have to remove the TB for cleaning, NEVER remove the TPS.

Gordon charges 10 bucks a minute!!?? Holy crap....that's 600 bucks an hour, 4800 bucks a day...wow.

I think that's obscene

In my opinion, there's nothing that Mr. Killebrew knows that's worth that much. In addition, based on observation or anecdotal information about his work with others, my opinion is that his depth of knowlege is lacking in some areas. If your call concerns a question about an issue Mr. Killebrew has adequate knowledge to speak on, the price is excessive at best. If the question covers something he lacks knowledge/experience about, in many cases perhaps he will still answer, but the cost of what you may get is, in my opinion, obscene.

Heck...I oughta go into that sort of "tech support".

Even if I charged a quarter of that, I'd probably make more money than magazine writing pays.

 

[Paul Higg]

Okay Hib, if you are so smart then why couldn't YOU help with my TPS installation problem?

 

[Paul Higg]

Stop sending me answers to my posts if you're only going to denigrate or humiliate someone. You need to be a little bit more humble sir.

 

[Hib Halverson]

Okay Hib, if you are so smart then why couldn't YOU help with my TPS installation problem?

I didn't discover this thread until after you fixed the TPS, so any comment I'd have made along those lines would have been irrlevant. In the future, if you have a problem like that, please contact me privately. I'll try and help and, to the extent I can help via email or by phone, I'll do it for free.

Stop sending me answers to my posts if you're only going to denigrate or humiliate someone.

I did not send you an answer. I posted to a public discussion forum. In case you misunderstand how forum sites like Corvette Action Center work; on a public forum, anyone can post to a thread you begin.

My statements about Mr. Killebrew do not denigrate or humiliate you or him. I expressed opinions about the price he charges for his service and the quality of the service, both of which are legitimate issues to discuss on the public discussion forum which is the CAC

You need to be a little bit more humble sir.

Thank you for the suggestion, Paul.

Your demand that I stop answering posts you make to a public forum implies some arrogance on your part, so I'll suggest, in return...

You need to be a little less arrogant, sir.

If I'm a little more humble and you're a little less arrogant, maybe we'll meet halfway.