Gents/Ladies,

Just bought a 2001 S40 T4 (1948cc). Fantastic car (also own a 1.8 GDI which is currently suffering from mysterious loss of power to dash board/ignition!) and drives wonderful with 91,000 on the clock.

Problem is: car starts ok, turbo kicks in at around 2,500 rpm (i think), and all is well. However, after running the car for a good 45min-1hr, the same 'pull' I feel when the turbo kicks in no longer occurs. Instead, I get pretty much constant acceleration (although still pretty quick). But the distinct 'pull' when the turbo kicks in is no longer apparent.

I've also noted that the low-idle rev problem (erratic revs between 300-750rpm) also happens at about the same time...don't know if the two problems are linked...

The interesting thing is if I turn engine off, and start the car again, it seems fine (the turbo problem)...but then will show the same symptoms after a while.

Any ideas what could be happening?

Many thanks,

AJ

:00000732: :)

Moved to S40 forum

Hi

I know this isn't particularly helpful and reveals my incompetence at mechanics but i wonder if your loss of power is heat related?

Can someone else add their 2 cents?

Cheers

I had a similar sounding problem on my 850. Turned out to be a sticking turbo gate valve that only "failed" when it got hot. Some graphite on the pin, a bit of hand turning, and it runs fine.

You might get some more ideas by checking for fault codes (I don't know how to do that engine). 1. Read and write down the fault codes. 2. Clear them out. 3. run the car till you get a "failure". 4. Check for fault codes again.