rough running, power loss

**baloo** · 04-10-2008,09:22 AM

Hi,

VW transporter running rough and with power loss, seems to happen when engine under load. allow to tickover for 5 minutes and problem cured short term.

Any idea's anyody?

Cheers,

Baloo.

**ferretflasher** · 04-10-2008,04:00 PM

What model and what engine are you refering to ?? A bit more detail needed firstly...!!!!

**baloo** · 05-10-2008,08:53 AM

Thanks for your reply, the engine is the 2.5tdi AJT 88bhp 2003.

**T5 TDI** · 11-10-2008,03:57 PM

That's an odd one baloo. The only thing I can think of that changes after 5 mins or so idling is the EGR valve. It can be open at idle but closes after a while (I think that's the right way round!)

Also, it should also be closed at full throttle but perhaps yours is open causing the problem. It might show a fault code if you can find someone with vag-com and you can check what it is doing with vag-com too. They can get quite sludged up after a while.

**trog48** · 15-10-2008,05:45 AM

i hope you are not about to have the problem i had. was finally diagnosed as faulty injector pump which was replaxced with new, and then required new turbo as original was coked up due to injector pump fault.

**oscart4** · 18-10-2008,02:56 PM

My understanding of the EGR is much the same, I believe it should only be open at tickover and when at cruising revs, it only closes I believe when you are accellerating.

**T5 TDI** · 18-10-2008,05:24 PM

The change in the EGR state is the hopeful thing here. I only know about the 5 min idling thing from the Erwin manual I had when I had my T4. I have a 174 T5 now :-) Fitted the modified water pump today, strange job for a water pump but not too bad!

**baloo** · 22-10-2008,11:07 PM

Hi,

T5 174 would be nice, maybe one day

Van has now been tested with the EGR blanked off and the problem is still the same

VW replaced the EGR stating this was the cause (another thread on here) a lot of people are saying air in fuel, but VW insist that the fueling is correct

I have looked at the return pipe, well i think it is the return, for air bubbles and all seems well with no air bubbles.

Doesn't make sense that if the van is allowed to tickover then it runs fine for a short while, if the rough running returns then allow to tickover for 5 minutes and problem cured again, This applies to when first started in the morning too, ticks over a little lumpy, give it a few revs and allow to tickover and runs fine........... if you keep the revs down. If making the van work harder (up Hill) then the rough running returns instantly