unsolved mysteries. 1.6TD (dies at temp)

[sk8ordie]

I recently drove my 1.6TD powered caddy 6 hours (it ran great). When I reached my destination - I changed all exhaust related gaskets as I was tired of eating soot.

When I tried to start the truck back up - it ran great for a few minutes - then died once it reached temperature. I can keep it alive, but if I let off throttle it will stall. The truck specifically dies out when under load/ going up hill. At idle the truck sounds like its running on 3 cylinders.

To correct these new behaviors I tested (then replaced) the injectors, timing (set correctly). After changing the injectors, I started the truck and it ran perfect. When I took it down the road - it started to die out and lose power. I limped back home - let it cool off - then drove it again. Ran like a champ - and it pulls hard, however, it will die off throttle, and wants to hesitate.

any thoughts would be appreciated. all lines have been replaced. Clear lines will hold a prime for weeks. There are some bubbles in the feed line, but much less after new injectors, and less than there were when I drove the truck for 6 hours without issue.

[R.O.R-2.0]

should have started out by replacing the fuel filter..

they are super cheap, and it is likely the root of your issues..

[sk8ordie]

Should have been more detailed with what I've done.

New hard fuel lines. New soft fuel lines, new fuel filter, new copper washers, new clear feed and return lines. I'm not arbitrarily throwing parts at it. I'm replacing worn parts after testing them.

That's why this is now a mystery.

[TylerDurden]

I'd bottle feed from a clean jug, and check the return flow...  The IP can overheat if the OUT orifice is plugged.

[ORCoaster]

By replacing the gaskets did you seal up the exhaust and now have a back pressure situation that is preventing good flow through the pipes?  Plugged muffler that needs blown out?  Sounds like it can't get rid of the exhaust at higher RPMs to me.   Just food for thought.
 
DAS

[sk8ordie]

I'd bottle feed from a clean jug, and check the return flow...  The IP can overheat if the OUT orifice is plugged.

Thanks - I'll Give that a try.

By replacing the gaskets did you seal up the exhaust and now have a back pressure situation that is preventing good flow through the pipes?  Plugged muffler that needs blown out?  Sounds like it can't get rid of the exhaust at higher RPMs to me.   Just food for thought.

I though I must have somehow left a rag in one of the flanges - so I pulled the manifolds, turbo, and exhaust back off for inspection. And Looked inside all the head flanges. Nada.

It smells like a dead animal when it stalls. I can imagine one would get inside the engine beyond the areas I mentioned above.
 
DAS

[sk8ordie]

Mystery solved - turns out it was a hefty kink in the hard return line from road debris. Thanks to everyone for your suggestions.

[92EcoDiesel Jetta]

Mystery solved - turns out it was a hefty kink in the hard return line from road debris. Thanks to everyone for your suggestions.

huh? what hard return line?

[R.O.R-2.0]

Mystery solved - turns out it was a hefty kink in the hard return line from road debris. Thanks to everyone for your suggestions.

huh? what hard return line?

on mk1 cars, the fuel lines are metal under the car..

[ORCoaster]

Road Debris?  More like pilot error.  Hey what is that rock doing in the middle of the road.  OH crap, avoid avoid.   Clunk, clunk clunk down the rightside.  Then later.  Poor performance problem.

[8v-of-fury]

huh? what hard return line?

on mk1 cars, the fuel lines are metal under the car..

They are still a "hard" line on the mk2 and mk3 as well.. haha just plastic. Gotta love the mk1 lines though.. damn near 3/8" ID or something close. hahah