Touareg: 2008 V8
Join Date: Oct 2014
Second Vehicle: is jealous
Thanked 2 Times in 1 Post
Just a little update in case somebody ever has this same issue since there is 0 info on it.
There is no info on what injectors are in each group (A,B,C,D) We (friend and I) check the diagram and assume that Group A was cylinder 1 and whatever adjoining cylinder was in the diagram. After several checks, the groups follow the ABCD/Cylinder 1234 layout. The remaining cylinders are whatever is matched to the 1,2,3,4 injector.
Example- Group C injectors is Cylinder 3 and 5
In the case for my touareg, I took the intake manifold off and found that cylinder 5 had slightly low resistance @1.8-9ohms compared to the rest that were 2.2 ohms. I doubted this difference could cause the poor running that I had, felt like the truck dropped 2 cylinders. I reassembled it and took it to the dealer thinking it was an ECU issue and its still covered under emissions warranty.
They re-diagnosed it, decided to put in an overlay harness for both 3+5 cylinder and I paid for new injectors just in-case. I still thought it was an ECU issue. It went back together, was road tested and everything is good!
I never thought that the little difference in the injector would cause this much of an issue but it does. It felt (when driving) as though the ecu shut off both cylinders in that group.
Hopefully it doesn't happen again but it was a good learning experience. Several VW and Audi techs I know all had never seen the issue. The tech that repaired mine also said there is no info on the fault and he followed the same path that I had except he doubted the injector where I thought it would be ok.