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RPM jump in first gear

Habnixzuverliern
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Habnixzuverliern Enthusiast

Habnixzuverliern

Posted
Posted

Hi,

after a while i have now again a problem with my truck. I will try to explain what the problem is.

if i accelerate from stop to 35mph, the rpm start going up to 1200 and then there is a hard jump about 200rpm to 1400.

This only happens from stop, not from slow speed. I had this morning a problem which disappear but the speedometer showed the wrong speed till 25mph and then it jumped up to the right speed, while i had this problem the transmission worked okay, after work started the truck and the RPM jump is back and the speedometer is correct.

 

I am not sure, if its a engine or transmission problem, there are no dtc in the truck.

I am happy to get some ideas what the problem might be as i am stucked.

 

Thanks

 

Pierre

Snowcamo Senior Enthusiast

Snowcamo

Posted
Posted

Transmission issues. Likely time to rebuild. I'd not keep driving like that as it'll just get worse. Take it to a shop for diagnosis. Sounds like torque convertor or pump issues

Habnixzuverliern Enthusiast

Habnixzuverliern

Posted
  • Author
Posted

Hi,

 

Problem is to find some one in Germany wo want to touch those cars.

What confused me is that its not happening all the time and what i saw in the data is that the pedal position is stady but the throttle position is dropping, which makes no sense for me.

 

Also some information which i missed, is the car was staying for 10 days as i had contact to a person who had Covid, so i didn’t left the house, when i parked the car, all good and after that it started.

 

Thanks

 

Pierre

A8D8DEFE-AAB2-4AC9-816B-1F9E34AEAB8D.jpeg

Habnixzuverliern Enthusiast

Habnixzuverliern

Posted
  • Author
Posted

Hi,

 

is it possible that this is a problem with the speed sensor. When i start, i can see that the speed sensor is not recognising the speed correctly till about 25mph then it kicks in. Where did the speed sensor sitting?

 

Thanks

 

Pierre

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