Stalling

[Mike327]

1994 F350 7.3 IDI turbo

Recently it has started stalling on me but will restart without a problem. I first noticed it would stall when I let off the pedal and began coasting to slow down for a stop sign or red light. I then noticed that if I rev it up while idling in park and let off it will stall. Any ideas what I can try to fix this?

 

[franklin2]

Sounds like some mystery thing in the injection pump may be sticky or going bad. I know nothing about the guts of the pump, there is not much you could do about it anyway. But people do take the fuel filter off, pour the diesel out of it and then fill it with automatic transmission fluid, re-install the filter, and then start the engine and run it for a minute and then shut it off and let it sit for a day or so. They have had success freeing up things that might be stuck inside the pump doing this.

 

[Mike327]

Ok I will give that a try and see what it does.

 

[lotzagoodstuff]

Just wondering: what's your idle speed according to your tachometer? Might be something really silly like the throttle stop screw backed off just a bit. It's common to turn up the idle on manual trucks with single mass flywheel conversions to quiet down to gear rollover noise. If it were me, I'd bump it up 100 rpm and see if it goes away. If it doesn't go away, you will have identified that you could have something wrong with your pump or fuel system.

 

[junk]

My 93 had the same problem. If I run a fuel lubricant it's fine. If I run straight diesel it dies. Seems better after hundreds of miles with fuel conditioner. I'm not at the point it doesn't die every time i run without conditioner.

Franklin was right. There is a deal in the pump that gets sticky. Fuel additives worked for me.

 

[gandalf]

You've named the classic symptoms of a sticking metering valve in the IP. You may be able to cure it with fuel conditioner in each and every tank of fuel, and the ATF in the fuel filter, but I'd start saving your lunch money for a new IP.

 

[Mike327]

Well I did the ATF in the filter trick and let it sit a day. I started it up and drove the mess out of it. Hasn’t stalled out since. Thanks for the help.