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RPM's sticking @ 2000/80kph

04-silver

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04-silver Enthusiast

04-silver

Posted
Posted

Hi all

Anyone have this problem? I think its a problem.

Dealer says I have all the latest software.

 

This is what happens:

 

truck shifts fine, 22-2500@30k's, 22-2500@60k's (approx #'s) When I continue to gradually increase to 80kph the RPMs drop down from 2500 to 2000RPM, same as before except now when I continue to accelerate from 80 kph the RPMs will not budge from 2000 and I do get a slight grinding feeling from the gas pedal, I will get the truck up to about 105/110 kph before the RPM's eventually jump to 22/2400.

 

The only other way I can get the RPM's to increase is to either punch on it hard or take my foot off the pedal for a split second and re-apply.

 

:crackup:

John

2001 HD Enthusiast

2001 HD

Posted
Posted

Your truck is pretty new, but you might check your throttle body for carbon build-up behind the throttle blade. It may also be something in the electronic throttle accuator. There is some kind of sensor on the peddle and a servo on the throttle body. My truck uses a cable, so I'm not to familiar with the fly-by-wire throttle systems.

 

:crackup::devil:

millerwd Enthusiast

millerwd

Posted
Posted

That sounds pretty much like mine. It wiil try to accelerate in OD if I don't push it.

See what happens in "tow" mode. It has higher RPM shift points.

04-silver Enthusiast

04-silver

Posted
  • Author
Posted

I don't know, beats the L outa me, maybe its just me looking for things to go bad :crackup:

 

But it does seem odd at that particular spot, whether in D, 3, Tow Haul, Auto or 2W doesn't matter always seems like the RPM's get stuck at that point.

 

Should't the RPM's always show an increase of some kind when your accelerating,

Especially when there is a difference of 20 to 25 kph?

 

I've been trying to borrow my buddies vid cam and record this.

 

:devil:

John

Butch 02 Denali Enthusiast

Butch 02 Denali

Posted
Posted

It's the torque converter clutch locking when you see the rpm's drop to 2000. Why it doesn't go up from there is a good question. Sounds like a VSS (vehicle speed sensor) problem to me, or some corruption in the PCM program. The dealer only sees that the program is there and functioning. It cannot see if the program is corrupted if no codes are being set.

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