54 reg 2.0 TDi Idle during warm up

[mjtray]

I suspect that this question may have been asked before as I've seen other questions being asked on other forums, but I never seem to be able to get the full answer.

 

I have a 54 reg Octavia II with the 140bhp 2.0TDi engine. Great car and has given me sterling service, however, the one thing that seems to be getting worse is the idle during the warm up period.

 

I know that these 2.0 TDi's have a lumpy idle at the best of times, but mine is getting quite bad during the warm up period, ie the injectors sound like they are missing a beat. There are no misfires so to speak of, just a very erratic idle. As soon as the engine is up to temperature its as good as gold.

 

At no other point through the rev range are there any flat spots or drop in performance, either when the engine is cold or hot. Both performance and economy remain excellent.

 

So far I have had the coolant temp sensor replaced (with a genuine sensor, not pattern) as that had thrown up a code, but that has made no difference at all.

 

Any thoughts on what's causing this....anybody had the same problem

[Guest]

My first thought would be a diesel additive and an Italian tune up.

[mjtray]

Nope...done that