[enobeenob]

Originally Posted by mikeymike

Doesn't the vss have to be adjusted/calibrated also?

No, it does not need to be calibrated. Just R&R and go on down the road.

[kifa]

Thanks guys it was really helpful, i cheked the wires and realized that the battery had not good connection. Now car works fine but the odometer still doesn't work. If i'll change the VSS is it gonna change anything? What else may cause the problem that odometer doesn't work?

Have you noticed if it acts up ALL the time or only when it is fully warmed up? Mines will only do it after it has been running for about 1/2 to 1 hour. Then it will continue to do it after that.

It's sometimes shows the right speed but most of the times it's just dead or stuck on any random number. It's doesn't metter if you just started the car or driving a long time it's always the same.

[cumminsM11]

I just got my truck back from the shop after the CVI and the yoke nut was tightened at the same time. The pick up for the speedsensor is on that output shaft of the transmission. You will need to go under the truck and see if there is any play in the output shaft of the transmission. Push it up. if you can move it up, 90% chance that is your problem with the speedo. When you accelerate the output shaft moves and so does the pick up for the VSS, causing an erratic reading. That is why when you took you foot off the throttle, it went back to normal. I had the same thing happening to my Volvo, and my FLD. Tighting the yoke nut is about 2 hour job, and your truck will also run a lot smoother. Now I have no vibrations at any speeds at all. MY SPEED IS SHOWING ACCURATE AFTER ABOUT 4 MONTHS OF THE NEEDLE JUMPING UP AND DOWN. My speed would also show OK after I let off on the throttle, and drop after I stepped on it. As the play gets worse on the output shaft so will the frequency of your speed not reading right. Also when you climb hill with a load and start shifting down, with every down shift, the needle will drop more and more. I got different answers from a few shops. What they said was not making much sense so I just left it. i am glad that the mech. tightened up the yoke nut and that was the problem all along. Anyways Good Luck with the problem. (Just curious, is it a car or the Volvo you were inquiring about, you mentioned the CAR is running better now with the battery connection all fixed up.)

[Kranky]

Cummins M11 wrote:

When you accelerate the output shaft moves and so does the pick up for the VSS, causing an erratic reading

If the yoke is loose that will allow the trans. output shaft to move axially, but the VSS is screwed into the bearing retainer/seal housing on the transmission, and locked in place with a jam nut. I can assure you that "the pickup for the VSS" ain't gonna move.

If it does, you've got bigger issues going on.

[kifa]

My speed would also show OK after I let off on the throttle, and drop after I stepped on it. As the play gets worse on the output shaft so will the frequency of your speed not reading right. Also when you climb hill with a load and start shifting down, with every down shift, the needle will drop more and more. I got different answers from a few shops. What they said was not making much sense so I just left it. i am glad that the mech. tightened up the yoke nut and that was the problem all along. Anyways Good Luck with the problem.

In my case the engine works fine. I changed the VSS and still i have problems, odometer works when i start to drive but when i drive few miles it just stops working at all. Also on the car the backlights doesn't work(on the trailer works fine) Also when i drive on a bad road on few seconds engine break and cruise control stops working and computer shows a message "Check line control module".
What may cause this problems? Is this one thing that causes all this problems or there is a lot of small problems i have to find and fix???

[Kranky]

From my earlier post:

VSS (vehicle speed sensor) at the transmission output shaft is defective, or the connections or wiring between the VSS and the ECM have a fault.

It sounds like you have other wiring issues as well, causing your light problems.

A wiring harness is probably chafed somewhere and the vibration and bouncing while driving are causing an intermittent connection or short circuit.

Time for some detective work..

[cumminsM11]

I am just saying that I had the same problem, speed shows low when accelerating and OK when you are not touching the throttle. I never suspected the loose output shaft, but that was what teh problem was. So you can all say what you want. If it was the VSS, it would be doing it all the time. Anyways I am just speaking from what I have experienced. You can change anything you want on the truck. It will not fix your problem until you tighten the yokenut. 2-3 hour job, or put some washers behind the shaft like we did. Anyways what do i know. have a nice day.

[Rat]

I have been in contact with a Volvo repair shop and they also mentioned a loose Yolk causing this problem. But The one I drive has the Meritor 10 speed. Check the VSS adjustment first along with checking for looseness of the output yolk. Turn the VSS in untill it bottoms out then turn it out 1/8 to 1/4 turn. Also drop the drive shaft and tighten the yolk nut and see what happens.