Thread: Sudden loss of boost and high EGT on trip

Originally Posted by Don 130

G'day all, on a trip between Sydney and Canberra yesterday, I noticed boost and performance had diminished and EGT's easily and quickly rising on hills. 300 TDI with 410,00km pulling 1 ton camper trailer. I can manage to keep going by watching the gauges. I've done a roadside check of hoses and can't see anything amiss. Oh and there's a whistle evident which made me think hole in hose, but can't find one. Any clues?
Don.

Sounds like an air leak to me too.

I had a similiar problem with my 300tdi. It turned out to be a split in the small hose connecting the rigid pipe to the bottom of the intercooler. The split was on the bottom side, and impossible to see. Run your fingers over all of the flexibles to try to find any splits.

Aaron.

I should have added, I've recently replaced all the turbo pressure related hoses with new silicone jobs, but I'll search on. Thanks.

diaphragm in the injector pump?
What about the intercooler?
Alternatively could be a leak in the inlet manifold or gasket.

Do you have any way to pressurise the inlet manifold without the engine running?

When I added my t piece to the threads on the manifold, to check for leaking, I blew in some smoke( helps being a smoker ) and sealed it up, then added about 10psi air using the compressor from the turbo compensator hose.
All I wanted to see was no smoke coming out of that rear access where I added a t-piece where I took my gauge feeds.

Due to the whistle I'd be checking the inlet manifold. Length of tubing, one end to your ear, other end to various parts of the inlet manifold at the gasket to listen for louder whistling while the engine is running?

Is the wastegate valve moving freely?
I'm wandering what would happen if the wastegate seized in an open position?

What max turbo pressure reading are you getting?

I have to say it, check those silicone hoses. In my opinion, they aren't quite as brilliant as people are led to believe. I have just changed mine back to rubber as the originals which were rubber lasted 17 years.

Originally Posted by scanfor

I have to say it, check those silicone hoses. In my opinion, they aren't quite as brilliant as people are led to believe. I have just changed mine back to rubber as the originals which were rubber lasted 17 years.

Quite. A mate of mine fitted all new silicone hoses and the turbo outlet hose burst a few months later. A generic 4 ply elbow off ebay replaced the 2 ply one supplied originally.

Originally Posted by bee utey

Quite. A mate of mine fitted all new silicone hoses and the turbo outlet hose burst a few months later. A generic 4 ply elbow off ebay replaced the 2 ply one supplied originally.

There is the problem, 2 ply. All my 4 ply silicon hoses have survived 30psi fine for the last 4 years.

And failing it being the hoses - check the Intercooler for any damage.

You may have suffered some damage (stone hit, crack, fatigue etc).