Cough, choke, puke
 

My CTD has been acting weird lately.
The computer for the engine will automatically sense a load being applied while at idle and increase the throttle setting to maintain the idle RPM without stalling. When I start out from a stop sign I normally just let the clutch out in 2nd gear then apply throttle after I get rolling.

Lately if I stop for an extended time (3-5 minutes) and let the truck idle in neutral or with the clutch in, when I let the clutch out the motor will stall. It only does this occasionally and always easily restarts.

Sometimes if I am quick and stick the clutch back in I can catch it before the motor completely dies,then it will cough and sputter for about 5 seconds before it picks up and runs right. During this 5 seconds of sputtering, pushing on the throttle has no effect.

Any ideas?

Fuel filter, Lift pump.
Lets start with the basics first. What's your fuel pressure?
Any odd looking smoke from tail pipe? How's the oil level and smell?

I am overdue for a oil change (about 5K since last) so the oil is black and sooty, level normal. I dont notice a unusual smell other than dirty diesel oil. Dont notice any unusual smoke and power is normal under load. I changed fuel filter about 8k ago. The only thing out of the ordinary is I just returned from a 4K road trip and bought fuel at 15 places from Seattle to Denver.

Update on engine stalling:

I had a unrelated wiper problem yesterday and went to the dealer. I checked the oil and it was about 3/8" over full (1-2 quarts?) but it may have been overfilled at the last change. I got an oil change.

I asked about the stalling issue when I let out the clutch. The tech looked at it and said I needed a new $2000 clutch. The service manager tried to make me believe the clutch was getting hung up on the release fingers and causing the motor to stall. I think he is smoking crack.

The truck does not act like it has clutch issues at all, no slip, squeal or grind. I have over 1 inch of free pedal before it gets firm and disengages. Operation is always smooth.

The stalling only happens once every week or less. Let the clutch out and a stop sign and it will choke sputter and die. I can quickly push in clutch and it will still sputter and die. addidng throttle during sputter has no effect. Restart is easy.

Throttle Position Sensor?

Could the TPS be intermittantly go goofy and not throw any engine codes?
The engine has stalled 4-5 times and I never have seen a service light.

Don't know. That's just what is sounds like to me from your description of what it's doing.

Updates??

No updates. I don't get a code so I cant take it to the dealer and expect any help. Hasn't stalled in a while. Runs great otherwise. Drove 300 miles today on winding roads, got 22.5 mpg avg.

If your oil level is getting over full, you got a bad injector, and lack of rail pressure may be what's causing the issue. Have them do an injector compensation test, it'll tell you what injectors are performing 100% or lower.