multiple missfires

[1fast2liter]

And if it matters i have positive pressure when i open the oil cap i feel the air pushing out.

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

I think sat ill put a test pipe in place of tje cats see if that helps. With the apr tune i shouldnt see a light

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

Any way to measure thru vag if the injectors are running right or rail psi?

Miss spelled words courtesy Motorola electrify via tapatalk

[Jack@European Parts]

Not really fond of the no cat and test pipe.


It doesn't take long to swap injectors, coils, or plugs to isolate.

Verify intake and for any false air leaks.

Verify grounds, supply voltage bus, and pulse signal for coils packs and injectors.

Verify compression.

[1fast2liter]

Can i verify the pulse for injectors in vagcom? If do whar are the blocks.. looked thru the grounds and looked good. Couls are new and so are plugs even swapped in old set to be sure. Couldnt see and leaks in tip but will spray with some spray. The whole time the problem has never left cylinder 4. I am also gonna switch around injector too

Miss spelled words courtesy Motorola electrify via tapatalk

[spinningpedals]

subscribing as i'm having similar problems with my wifes a4 3.0, except the miss fires occur during idle and when traveling up steap grades. only on cylinders 1,2,3( the right side bank), swapped coils, installed new plugs.

[1fast2liter]

Well put another new coil in 4 still misses switched injectors 3 and 4 around still miss fires. Did notice that vag shows injector duty at almost 88%. Possibility that a new fpr could be needed.

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

Also pulled intake and checked it for cracks. Did notice their was a hose that went from a hard metal line to a valve looking thing that was broke. Fixed it bit still did nothing. Not sure what else to try. Crank position sensor maybe? Any other ideas? Were is the crank sensor in these?

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

Replaced fuel pressure reg still does it. Did notice with it un pluged it idles fine it seems. But with it plugged in runs the same.

Jack would tje secondary air pump cause symtems like this if it was faulty or whay ever? It seems in start up fpr the first min or so she runs smooth then she starts to idle like crap

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

Changed number 4 plug for new seems to idle a lil better. Gonna change out the plugs the the ones jack recomended....

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

Were are all the groinds located for the coil harness?

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

I think tje last thing to try is rrplace the whole coil hsrness. After putting new plugs in again it runs even wprse. So my thinking i moved the harnes out of the way to do plugs mayne cracked it again but worese this time

Miss spelled words courtesy Motorola electrify via tapatalk

[1fast2liter]

well yesturday after installing different plugs to see if that would cure the problem the car ran even worse.. so i deduced that the coil harness had to be bad. every time i have moved a coil or what not ive moved the whole harness eaither breaking wires on the inside or possibly arcing out were i cant see. took off the tape and re did the joint were all the grounds come together and she seemed to run a little better. the part that connects to the valve cover when removed didnt change the way it ran at all so thats why i figured to redo the grounds. like i said seemed to run better and able to get in boost a little now..... ordered new harness and will install this weekend. any good diys for it?