Help. Several days ago my 2003 F350 V10 starting stalling when applying the brakes. Replaced Brake booster, stoplight switch, IAC valve, fuel filter, fuel pump, fuel pressure regulator, MAF sensor. problem continues. Truck is hard to start, have to rev to keep running. The day this problem started the CEL came on. It is now off. Borrowed code reader, no codes showing. Sprayed brake cleaner on vacuum hoses, connections looking for vacuum leaks, none found.

 

Hi!,

Some codes are pending, and then set when they happen again. Your stall may show as a pending code, and then when the car runs without stalling for long enough, it clears the pending codes rather than setting them. I would check for pending codes right after a stall next time you can. I think a pending code can result in the CEL coming on, not 100% sure of that...

Can you give us more details about when braking does or doesn't result in a stall? Does any braking, no matter how small result in a stall? Or is it braking that results in a complete stop?

Also, does the car start right back up afterwards? I would think either electrical short/open from momentum shifting, or fuel pressure issues...

I had a Toyota that did this long ago, and I think it was a vacuum problem--you said you tested this, have you tried a vacuum line gauge?

Another car I had only did this when the tank was low on gas, I think the fuel sock/filter fell off the fuel pump or something like that. Does it seem like it could be fuel related?

Another car I had, it was a manual transmission needed work. When I would press the pedal to drop it out of gear, the transmission and engine still had some connection, and the motor slowed enough to stall.

When I read your post I also wondered about the grounding cable from the battery...

Anyway, more detail could help me.