Ok, so I did some hard thinking, and some research, and have came up with this, when my van is warmed up ((This means transmission too)), It will shift fine until it gets to about 35-40 and then it starts chugging, that is until I let off the gas real quick and push back down on it.

Now that got me thinking, my AVG speed that my overhead display said was 35, and I know well, that I normally travel 55 - 60 most of the time, so I was thinking, if my Vehicle Speed Sensor went out, and was only telling the computer I was doing 35 then the transmission wouldn't shift.

So can anyone tell me where this is on the transmission.
Is it an easy or hard fix?

I need some insight on this, please.

 

Come on people, 100 views in 7 hours and not a single reply, what is this? Can a person get any help in here.

 

I don't see how it can be the VSS. They don't fail like that, i.e., generate a signal that somehow tops out in frequency. Also, you'd see it in the speedometer and, chances are, the PCM will light the malfunction indicator. Your problem sounds more like the TPS is binding or has a worn spot in the sweep range.

P.S. Yours has the 4T60-E and thus see the VSS replacement document for the Lumina (same transaxle) at http://www.justanswer.com/uploads/MC...VSS-4T60-E.pdf.

 

Ok I have posted this on here before EinST, that I thought my transmission was going out, and after much debate and driving I have come to find it as the VSS, unless you know of something else that tells the computer how fast my tires are moving.

And BTW, thank you for the PDF

 

No, there's nothing else, the PCM cannot calculate the vehicle speed without the VSS input. The thing is, you can do whatever with the VSS but I woundn't go down that route. A failing VSS or VSS circuit will be seen in the speedometer and malfunction indicator. The PCM may even go into the limp mode. Chances aren't good that the VSS is the culprit in your case.

 

We actually found it out, It's a complicated mess of the Torque Converter, the catalytic converter and the muffler.

 

Oh, jeez, sorry to hear that. Thanks for the update.

 

Hello, I have a similar problem: https://chevroletforum.com/forum/ven...70/#post517917
Can you please share a bit more info what was the reason...

 

He hasn't been here for 15 years, you may not get an answer from MegaMiles.

 

Make sure the CAT is not clogged.