Slight judder

**Samdy Gray** · 15th March 2010, 12:35

My car (1.9CDTI 120) has developed a slight judder between 1500 - 1800 rpm.

I recently fitted a new EGR valve and the car ran like a dream. I'm now noticing a slight judder as stated above, but only under light constant acceleration, if that makes sense.

If I give it a bit of right foot through the revs then it pulls great, but if I'm driving like my grandma (so to speak

) it feels like it misfires slightly.

As it doesn't happen when I floor it I'm thinking it shouldn't be clutch related. Could it be a slightly blocked injector? Worth using some de-coker?

**neverton** · 15th March 2010, 13:03

Hi,
I have the exact same thing on my 3.0 V6 Auto 2005

Suggestions so far have been;

Timing Belt
SCV (fuel pump valves) sticking
Faulty or Blocked injectors

Hopefully your is simply a loose or faulty seal on the EGR though

**kamar** · 15th March 2010, 13:48

my car did this 150 cdti but then the spanner light was on my mate had a look and my 3rd injector plug wasnt on properly, once plugged on car was fine but mine has a slight judder on idle i think its the injector wiring or blocked injectors, im gona leave it as its not bothering me at the moment.

**Celes** · 15th March 2010, 14:22

I had this on my V6 CDTi. Replaced all 6 injectors and it was fine then. Try putting it into a high gear at low speeds and then floor it (from 1100rpm). If there is a knocking like sound it is very likely you have a blocked injector(s).

**Samdy Gray** · 15th March 2010, 15:31

I'll have a play around with the wiring when I get home, it's not got the blue tops on so maybe the 3rd injector mod is needed.

If it ends up needing new injectors what's it likely to set me back?

**Driver0069** · 15th March 2010, 22:26

First thing i would do is clean all the injector plugs then tie them up with tie wraps normally it is the 3rd injector that has the problem i had the same problem i did the plug and wiring upgrade today and now it works like a dream.

**lesj** · 20th March 2010, 00:17

Injectors are either £120 or £290 each dependent upon part number fitted (Eurocarparts). Also need 4 copper washers from Vx (about £6). To replace all 4 can take as little as 1.5 hours, or a day or so dependent upon how stuck they are. I've done a How 2, mine were fairly easy.
You also need a Tech 2 or Vaux Com to code the injectors to the ECU. Vx also recommend the replacement of the high pressure pipes, I used the old ones and have had no problems.