Hi, I have a 2010 Octavia MKII 1.9 TDi(BJB). It's done 190k KMs. It has a new timing kit and clutch set along with the flywheel. Its running a remap with downpipe. I have been facing an issue with the car for a while. Irrespective of it being a cold or start when the engine is hot, the car judders on startup. Sometimes the juddering is so violent that the gear level starts shaking. I had replaced the engine and gearbox mounts recently which I suspect were worn out due to this issue. I am suspecting the anti shudder valve but it's working normally. Please help?

 

 

 

I suspect the wiring connectors to one or more injectors is loose, depending on the severity it may show on a diagnostic scan.

 

You can test manually for a loose connection but it's not guaranteed as the problem is intermittent.

 

Unscrew the injector wiring connector from the engine head (in front of tandem pump) noting the orientation of the wires.

 

With a multimeter measure each injector's resistance to ground in the socket pins, the faulty injector connector(s) being identified as having a higher resistance than the others.

 

Here's the wiring details:

Brown/Yellow = Ground

Brown/Red = Injector 1

Brown/Green = Injector 2

Brown/White = Injector 3

Brown/Blue = Injector 4

 

If you identify a noticeably higher resistance on one or more then you need to remove the plastic cam cover to access the injectors.

 

In most instances you can CAREFULLY remove the connectors from the injector and CAREFULLY bend the female spade closed to give a more secure electrical connection to the male part.  I say carefully as the wiring insulation and connector plastics will have become quite brittle.  Don't worry about breaking the plastic though, the uninsulated connector isn't going anywhere.  Just make sure you work over a cloth placed across the engine head... small black plastic parts can fall into the engine.

 

Retest resistances before reassembling.

 

There are videos on YouTube showing how to do this fix instead of buying a new wiring harness.

 

Jaldy jaldy!

7 hours ago, MicMac said:

I suspect the wiring connectors to one or more injectors is loose, depending on the severity it may show on a diagnostic scan.

 

You can test manually for a loose connection but it's not guaranteed as the problem is intermittent.

 

Unscrew the injector wiring connector from the engine head (in front of tandem pump) noting the orientation of the wires.

 

With a multimeter measure each injector's resistance to ground in the socket pins, the faulty injector connector(s) being identified as having a higher resistance than the others.

 

Here's the wiring details:

Brown/Yellow = Ground

Brown/Red = Injector 1

Brown/Green = Injector 2

Brown/White = Injector 3

Brown/Blue = Injector 4

 

If you identify a noticeably higher resistance on one or more then you need to remove the plastic cam cover to access the injectors.

 

In most instances you can CAREFULLY remove the connectors from the injector and CAREFULLY bend the female spade closed to give a more secure electrical connection to the male part.  I say carefully as the wiring insulation and connector plastics will have become quite brittle.  Don't worry about breaking the plastic though, the uninsulated connector isn't going anywhere.  Just make sure you work over a cloth placed across the engine head... small black plastic parts can fall into the engine.

 

Retest resistances before reassembling.

 

There are videos on YouTube showing how to do this fix instead of buying a new wiring harness.

 

Jaldy jaldy!

Hi, There are absolutely no errors. Just the usual EGR insufficient error due to the Vacuum pipe being removed. I'll still get the injectors checked. Thanks a lot!