M923A2 dies when I hit the brake

[ichudov]

I posted another thread previously "M923a2 dies when put in gear".

Well, since then I changed both fuel filters and it does NOT die when I put it in gear, especially if I push the gas pedal a bit. It does drive.

However, the truck dies every time when I stop it with brakes. It is as if something happens in the transmission and it does not disengage from the engine upon brake application, so the brakes stall the engine. Kind of like if I tried to stop a truck with a manual transmission and forgot to take it out of gear.

Any idea what it may be? Why would use of brakes kill the engine?

 

[Scar59]

Sounds transmission torque converter related; the torque converter is stay locked up and not releasing.

 

[goldneagle]

Since you normally have to take your foot off the accelerator pedal in order to apply the brakes maybe you still have a fuel feed issue. (not enough fuel going to IP) You may have a an air leak in your fuel line or filter housing. Try applying the emergency brake lever to stop the truck while still giving it just enough fuel to keep the engine from staling. The spring brakes should be able to hold the truck at low RPMs.

If your engine is not idling without help from you in Summer weather than you still did not resolve the first problem. Your 2nd problem may be your first problem unsolved.

 

[Floridianson]

I will jump on the Scar59 train. Would unplugging the lock up solenoid I believe is on top of your trans. change the problem.

 

[MtnSnow]

Double check the button in the end of the transfer case shifter and make sure it is fully popped out.

 

[98G]

Bump it into N as you come to a stop and see what that does. If it still dies, then it is probably fuel related.

 

[ichudov]

I will jump on the Scar59 train. Would unplugging the lock up solenoid I believe is on top of your trans. change the problem.

FLoridianson, I have a feeling that you are on the right track. Can you explain me where approximately that lock up solenoid is on top of the trans?

That solenoid malfunctioning would provide a good explanation.

Thanks!

 

[Floridianson]

You might try what 98G said and just shift into neutral to check. I only had a 939 series for a short time but if I remember right it is on top of the Trans. on a line. The other question would be where is the sensor that controls the solenoid? I also lost my computer and all the good TM's

 

[ichudov]

I will jump on the Scar59 train. Would unplugging the lock up solenoid I believe is on top of your trans. change the problem.

FLoridianson, I have a feeling that you are on the right track. Can you explain me where approximately that lock up solenoid is on top of the trans?

That solenoid malfunctioning would provide a good explanation.

Thanks!