Possible injector problem? or loom? any help appreciated!

.Jas.

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Hi all,

I have a slight misfire when cold that starts a few minutes after the car has been started.
The car has been scanned with VCDS and no related fault codes came up. I have a 3.0 tdi quattro.

Running tests on the injectors using VCDS (using test blocks 13 and 14) comes up with the following:

After 1 minute of running all seems normal:
(6 injector readings)
0.66 mg/str | 0.24 mg/str | -0.80 mg/str | -0.33 mg/str | 0.00 mg/str | 0.28 mg/str

After 2/3 minutes of running we now encounter a slight misfire and the readings are:
-1.18 mg/str| 0.61 mg/str | -1.88 mg/str | -1.60 mg/str | 5.04 mg/str | -1.08 mg/str

When the car is warm (another ~5 minutes later) the car drives perfectly and the readings are:
0.14 mg/str | 0.24 mg/str | -0.38 mg/str | -0.19 mg/str | 0.14 mg/str | 0.00 mg/str

To me, this shows that 1 injector is playing up when cold. But why? Is it the injector, the wiring loom, the ECU, the injector seal, something else? Any ideas fellas, I'd love to get this fixed.

Are there any easy tests or changes I can do to rule out a few things?

Cheers

Jas
 
Hi .jas.Not sure if it covers the 3.0 tdi engines but there has been a recall on injectors and wiring looms.might be worth popping down to your local dealer and asking them if it applies to your car?:think:
 
TBH its one of those jobs where I would swap injectors around to see if the fault moves to a different cylinder, if so, you know the fault lies with injector, if not then its discounted an important expensive part.
 
pburv - i'll check but don't think there were any for the 3.0 engine.

NHN - cheers, is it easy to swap an injector? I doubt it's as simple as a spark plug usually is?