No boost after 30 mins of driving (tdi75)

J

Jimmy Gnarl

Member
Hi Everyone,

Got a strange fault with the 1.4tdi.

Starts and drives really well for the first 30 mins or so with full turbo boost but then turbo decides it is not playing anymore and only gives boost up to 2000-2200 revs then dumps it and makes a misfire feeling. Like pressure is starting to build.

It is not full limp home mode and does not reset with engine off/on.

Thinking its a sticky wastegate that only sticks on high temps?

or the N75, but if this is at fault would it be flat from start up?

Also 2nd gear is a pain getting into when dropping down from 3rd (changed gearbox oil )

Anyone any ideas.

Cheers

Jimmy
 
It definitely sounds like it's temperature related. With the colder outside temps, it can take 20-30 mins for a TDI to warm up properly.
 
It's normally the crankshaft and camshaft sensors that cause issues on the TDI'd when they get hot, but i can;t see how either would affect boost in the way yours is.
 
Intercooler end cap split and seal blown out.
Porous or loose pressure pipes to / from turbo and N75 valve.
 
Last edited:
I could do with one of those mini inspection cameras to see if the wastegate is sticking during use. seen some on t'internet that plug into your phone
 
Yes it may take that amount of time or even longer for the part to warm up and the gap to appear / open. Same goes for the N75 tubes and fittings especially the right angled one on the back of the N75.

When my intercooler split the limp mode was at exactly the same place every day... Just coming off the A470 and turning onto Nantgarw Hill.
 
You must log in or register to reply here.
Back
Top