P0202 fault on Mk6 Golf TDI

[coops53]

Hi, newbie to the forum here, am after some advice. Bought my 2010 Golf TDI second hand in Apr 15 and it was running ok (although sometimes taking 2 attempts to turn over on start up). A couple of weeks ago whilst driving home it cut out completely. When restarted there was a lot more vibration and the car would lose power whenever it went over 2000rpm. I basically had to crawl home at 20-30kph.

Tested it with my bluetooth ODB and it comes up with error code P0202 - Cylinder 2 injector Circuit malfunction. I cleared the error code and it came back straightaway with the excessive vibration still noticeable at idle.

I have checked the wiring to all cylinders from the harness and it appears to be intact. With the connector to Injector 2 disconnected there is no noticeable difference to how the car behaves at idle. I checked the resistance at the 2 pins of each injector. Injectors 1,3 & 4 show infinite resistance whereas injector 2 shows approx 120ohm resistance. I have not seen an internal diagram to these injectors and so cannot say whether either reading makes sense, apart from that there is clearly a difference between injector 2 and the others.

From these readings I am assuming that there is a fault with the electric circuit within injector 2. Is this a fair assumption to make or do I need to conduct further tests?

If this is the case do I need to replace the entire injector? Or is it possible to repair or replace just the solenoid/actuator part of the injector? Also can this be done at home? I am fairly competent with maintenance but would need to get at least a spline socket and possibly other tools to get the injector out. I have seen videos online for removing the older type of injectors but nothing regarding a Mk6. From the looks of it, it appears pretty straightforward i.e. remove connector, remove fuel lines, remove collar and take out injector but this is just from a first glance.

Any advice would be greatly appreciated.

Coops

[h100vw]

I'd be surprised if the 3 "Good" injectors are open circuit effectively. That doesn't sound correct. Is your meter autoranging?

From those results, I'd say you have one serviceable injector.

I don't know what the resistance of an serviceable injector is though.

Gavin

[coops53]

Just seen this video:

https://www.youtube.com/watch?v=DFLc7hEKnUk

I had the resistance set too low on the multimeter to indicate the resistance of the functioning injectors. They are actually showing ~200kohms whilst the suspect one is showing 120ohm. Think that I just have to go ahead and order a new injector and see if that fixes it. Swap out actually looks pretty simple as I downloaded the workshop manuals from Erwin.

[h100vw]

Just seen this video:

https://www.youtube.com/watch?v=DFLc7hEKnUk

I had the resistance set too low on the multimeter to indicate the resistance of the functioning injectors. They are actually showing ~200kohms whilst the suspect one is showing 120ohm. Think that I just have to go ahead and order a new injector and see if that fixes it. Swap out actually looks pretty simple as I downloaded the workshop manuals from Erwin.

That's where I was going, if the resistance is over the max selected, it calls infinity.

Maybe one of the WV mechs will chime in and confirm for you.

Gavin

[harlie]

If you want to be sure, swap injector 2 and 3.
If it is the injector is faulty, when you unplug #2, the engine should change - when unplug#3 there should be no change because the faulty injector is now in 3.
However if the problem is still at #2 then it would be the harness.

[Umai Naa!!]

Make sure you replace the injector bolts. They're single-use on these, and need to be torqued to spec.

Also, the injector may need to be coded to the ECU. You will need to input the 5-digit code off the injector into the ECU. Not sure if VCDS/Vagcom can do this, so it may require a trip to the dealership.

[coops53]

All sorted, new injector bought and installed. May need to calibrate at some stage but runs ok without right now