Hi guys

 

My skoda octavia 06 plate 1.9tdi has been rock solid for the year ive owned it.  Mountains of history and a recent service and cambelt and pump change.

 

Since the cambelt change its developed a judder under load - normally pulling away and normally going up hill but not always.  During an hours drive it may happen a few times or it may not happen at all and everywhere in between those guidelines.

 

Its not the timing (I've had it checked by 3 independent mechanics and been told it is absolutely spot on to the point theyre impressed)

 

I've heard stories about injector looms playing up with the same kind of symptoms but other than this I'm at a loss.

 

Anybody have any ideas or experience?

 

Thanks!

 

 

If timing OK then I'd replace the injector wiring loom first - it is a common fail especially when disturbed. The wiring within the head sits in oil and eventually deteriorates. It's a pretty cheap and easy replacement.

 

Any codes stored?

cheers John 

 

Nope - 2 laptops plugged in and no faults showing.

I'll probbaly get a quote for the wiring loom to be replaced if its not a massive job?

Thinking of anything that might have been disturbed during the cam belt change - another thought might be an engine / gearbox mount?

 

• The first thing I mentioned (wiring loom) usually would cause a judder as it could drop a cylinder (or two) under some circumstances
• An engine/ gearbox mount could cause judder as drive is taken up or put under pressure ( eg putting foot down to power up hill!). On my old petrol mk I Octavia the mount between the top of the gearbox/ chassis failed causing strange noises at times. These can be disturbed/put under pressure during a cambelt change.

 

 

 

Edited 1 July, 20205 yr by bigjohn

I would get the cam timing (torsion value) checked on VCDS, be especially wary if the result is zero indicating that it is spot on, it probably means that its outside of measurable limits, if its at zero then check it when the engine is revved to 3 or 4K rpm, the belt stretch should bring up a -ve reading which will probably be a +ve one because VCDS gets most things backwards.

 

If they just replaced the belt without setting up the torsion value using the vernier pulley adjustment it will most likely be out, if out far enough it could cause your problem, as the problem started after the belt change its a strong possibility.

 

I bet most garages never do it.

 

Editted, 3 mechanics checking the timing and being impressed, was that with VCDS or similar?

 

If so then it points to the false zero syndrome (its almost impossible to set it fine enough to get the zero degree desired value), get one of them to check that it varies when revved.

Edited 1 July, 20205 yr by J.R.