Octavia 2 1.9  PD Rough/hesitant running, down on power, poor starting.

 

Started around time cambelt was changed but can't be sure that this is linked.

 

MAF sensor is new, fuel filter replaced, EGR valve cleaned.

 

Running becomes significantly worse once engine is fully warmed up - wondering if this provides a clue to narrow down probable cause a bit.

 

Thanks

 

Timing and or pump probably a tooth or two out of correct position.

As it's a PD there will be no pump timing to worry about, but I agree the first thing to check is the belt timing. 

Been out and took top part of cam belt cover off.

 

From the positions of the bolts in the slotted holes in the camshaft pulley it would appear to be very advanced - at the extreme end of the adjustment. Occurs to me that this does not guarantee that it is advanced though. If the cam pulley moved by a couple of teeth (retarded) you could use up all the adjustment in the camshaft advance direction and the cam would still be retarded - If there are any flaws in that thinking feel free to say.

 

Anyway back to garage and get torsion value set on VCDS

 

Anyone got the official torsion value setting - gather it should be fairly close to zero.

 

Thanks

Edited 10 February, 201610 yr by Octy0GG

Get it back to whoever done it, mine was bodged and ended up going back 3 times before they would admit the timing was out, even took my laptop with VDCS to show them, and had to explain that I was a mechanic too, then all of a sudden they said we will have a look, and the timing was out.

 

The car was fine when cold, was lumpy when warm and got no power when hot.

 

Hope this helps.

 

 

Trev

Update

 

Still as bad as ever, down on power, poor running, poor starting. Taken back from garage, turned off, went to start 10 mins later (so still warm) starter turns engine at normal speed but will not start.

 

Torsion value had been at -3.4 after belt change but now adjusted to +0.5 degrees so cam timing should not be problem.

No fault codes on VCDS

Can't see any loose or damaged vacuum pipes or electrical connectors.

 

80000 miles on engine, I got it at 30000 and I haven't given it a hard time.

 

Getting a bit depressed at this, not to mention nostalgic for carburetors and pushrods and getting a bit annoyed when I see references to the bulletproof reliability of the 1.9 PD engine.

 

Any ideas about possible cause appreciated.

Should also say has not been wrong fuelled in my 4 years ownership.

It's a bit strange.....I was thinking you might have a faulty cam position sensor or crank position sensor. However there would be a fault code and check engine light if this was the case.

 

Another idea is the injector wiring loom inside the rocker cover.....this can chafe and short causing poor running. But again you'd probably expect a fault code of some sort to be stored. 

Got the car through an MOT today so emissions can't be too awfull