TPS and Tranny cant get along under load!

[HotWheelsBurban]

Thanks, pretty savvy at where they are... just not sure how they play into my problems or if they could be contributing factor.

I think the reluctor wheel is in the back side of the rotor. Not sure since it has been 3 years since I had the rotor off. But makes sense that's where it is....

 

[Pinger]

Its a 2wd 4L60E and the VSS is on the pass side of the tranny tail shaft. No, the speedometer is 10mph fast. It was that way with the old VSS and this new one.

Is it the correct part - I'm guessing yes as it's only the sensor part - not the wheel?
Any possibility that the gearbox has been changed from a truck with a different axle ratio? Is it out by 10mph at all speeds or is there a percentage error?

The front rotors are new so, I am guessing there arent any cracks in the rings. Not sure about the front speed sensors though - don't know if they were replaced with the brakes. When I got the truck all the brakes had been replaced and its always had these problems since I bought it. I have stock size tires on it... 235/70r15 so, no weirdness there.

Rings should be fine if new.
Front sensors - I'd expect the ECU to self check them on 'key-on' and any faults throw the dash light on and it remain on so probably OK there.

 

[TacosnBeer]

Is it the correct part - I'm guessing yes as it's only the sensor part - not the wheel?
Any possibility that the gearbox has been changed from a truck with a different axle ratio? Is it out by 10mph at all speeds or is there a percentage error?



Rings should be fine if new.
Front sensors - I'd expect the ECU to self check them on 'key-on' and any faults throw the dash light on and it remain on so probably OK there.

I don't think the tranny has been changed. Just the motor from what I understand. As for the percent of error... its 10mph all the time at any speed. It isn't throwing a code for abs sensors, just the erratic vss now. (oh and the brake switch a little while back)

 

[TacosnBeer]

Not sure if 4wd is different as far as where/what the ecm does with the sensor info, but I have cut the wires on my front abs sensors on both my '99 k2500 and '98 s10. This didn't affect the speedometer or shifting on either truck.

Wow, not sure why you would do that but, it didn't make anything different in the speedo or the brakes? Thats crazy.

 

[Pinger]

10mph over or under? What are you referencing it to - tachometer?

 

[TacosnBeer]

10mph over or under? What are you referencing it to - tachometer?

It is 10mph over. I used a GPS MPH app on my phone to compare my speedo to.

 

[Pinger]

It is 10mph over. I used a GPS MPH app on my phone to compare my speedo to.

Just to get the obvious stuff out of the way. The needle isn't sitting at 10mph with the truck standing still - like the needle is on wrong?
And GPS isn't on a hill?

You're going to answer no to both of those so you must have some electrical glitch. The stuff you describe all kicking off at the same time has to be connected.

 

[TacosnBeer]

Just to get the obvious stuff out of the way. The needle isn't sitting at 10mph with the truck standing still - like the needle is on wrong?
And GPS isn't on a hill?

You're going to answer no to both of those so you must have some electrical glitch. The stuff you describe all kicking off at the same time has to be connected.

The needle sits at zero.... then it gets going about just before 10mph and stays 10mph fast compared to the GPS speed on my phone.

I have checked and cleaned every ground on the truck, even replaced a couple.

 

[letitsnow]

Wow, not sure why you would do that but, it didn't make anything different in the speedo or the brakes? Thats crazy.

No difference in speedo - the brakes work much better. I replaced the abs box with an adjustable wilwood proportioning valve and replaced all brake lines.

 

[Pinger]

The needle sits at zero.... then it gets going about just before 10mph and stays 10mph fast compared to the GPS speed on my phone.

Hard to know if the +10mph is a symptom of the bigger problem or just a quirk.

I have checked and cleaned every ground on the truck, even replaced a couple.

It's the (IRC) the transmission, speedo, and ABS dash lights(?) all going nuts in synchro that's confusing. Can't help but wonder if there's chaffed wiring somewhere that's bringing wires into contact with each other where the should be insulated from each other. Then again, I had a smart where that kind of thing was commonplace.