Why is my accelerator pedal sometimes non-responsive? (Series 60 with B500)

[azdieselman]

My understanding is that Allison has to sign off on 6th gear enable. I have programming authority, But I'd have to contact HQ for the enable code. When that TCM was programmed they might have fudged on the vehicle application.

[belfert]

Boost pressure is the same as always.  It was the first thing I looked at on my Silverleaf when I was seeing problems.  The 11.1L Series 60 doesn't have much boost.

[blue_goose]

How much is not much?  You should have at least 25lbs. Max and about 10 lbs down the road.

Jack

[Ericbsc]

I have had the same issue. Unplug the harness from the ecm. Check the spring loaded contacts. They are very small and if they have been spread open it will make intermittent connection and you will loose throttle. It will not show an error code. Drove me crazy till I figured it out!!

[belfert]

How much is not much?  You should have at least 25lbs. Max and about 10 lbs down the road.

Maxing around 15 to 17 lbs.  I was told years ago here that the PSI I am seeing is normal for a an 11.1L Series 60.  The boost has been the same so I got my Silverleaf some years ago.