2010 Audi A4 2.0T, Quattro (B8 - CAEB): Fuel Injector Problems

[LarryCV7]

2010 Audi A4 Quattro
2.0T TFSI (B8 - CAEB)
153K Miles

My A4 strikes again! I replaced the fuel injectors about a year ago along with other maintenance in part due to milage and carbon issues. Ordered the ones that came as a kit from ECS Tunning. Fast forward to last week and I started having gas smell and got a very apparent ticking noise.

I figured I’d get the original OEM injectors professionally cleaned and pressure checked to reinstall them. Never got to as the car started running rough. I was at a stop light and pulled over as quick could, parked it, and shut it off. Tried to restart and it wouldn’t restart and the CEL came on. Checked the DTC and it had three of them, (P103A, P0301, P0304), all misfire codes.

Thought it wise to have a look at the plugs and coils.
- Cylinders #1 & #4 slightly oily with gas smell and slight carbon build up
- Cylinders #2 & #3 seemed normal enough to me.

I started a compression test just to see what I was getting for compression. The #1 cylinder had a strong gas smell and only got to 90 PSI before I terminated the test. Removed the gauge and turned the engine over and fuel didn’t just make a slight puff…it was like a damned fuel jacuzzi bubbling up out of the spark plug well. I stopped the testing took off the intake manifold and all the injectors. Didn’t really see anything notably wrong with injectors 1-3; however, #4 injector had carbon/soot build up all over the exterior of it. The white Teflon seal at the very tip was gone along with the black spacer…think they both melted off? Did a preliminary check of the intake valves: All had varying degrees of carbon/soot build up.

The obvious thing to do in my mind is replace the injectors with the now newly cleaned original OEM ones. Along with that new oil filter, oil, and spark plugs. My question: Is there anything else I should be checking/replacing/testing that I haven’t already mentioned? I haven't been around these engines very long...how concerned about these injectors malfunctioning should I be...Is my motor screwed?

Would appreciate knowledge from anyone that has dealt with this sort of thing before and what was done to fix it.

Thanks for taking the time to read this!

[beatsageo]

When doing a compression test you should disable the injectors by pulling the connectors/fuse/etc. Muddles up the results. The engine does not get hot enough (there) to melt the PTFE seals, my guess is they fell off on removal or were not installed correctly. I'd buy a new set of bosch injectors from rock auto, they come with the seals installed and do the oil and plugs like you mentioned. Try repeating the compression tests with fuel off after you get the injectors back in.

[LarryCV7]

I've pulled the fuse for the injectors (Brown 3 - 25 Amp fuse) still sprays thou... Maybe its left over fuel from the supply line? Are there additional fuses that's require being pulled...as I only saw the one?
I'll be checking both the cylinder and the injector cavity for any remains of the white Teflon ring/washer. The small black three finger looking lock I think it is was totally disintegrated.
Had the original injectors for the car cleaned by injector shop so will see how that goes.
Like you mentioned I'll try the compression test after everything has been cleaned and reassembled.

Thanks for taking the time to reply...I appreciated it thank you!