4.2L V8 Injector Replacement DIY?
#11
I've had these multiple cylinder misfires since July 2017, I always reset it through vcds but after a day or two it comes back. I have a second Audi which is an a6 c6 model 3.2 and i have a code relating to that in which you mentioned with intake flap motors being stuck open and to be honest on that one i have no misfires or issues but the check engine light for the intake flap motors being stuck open. But on this Q7 4.2L my boys cousin who works at the dealer plugged in the system they use there and it had an error showing clogged injectors. I lost contact with him but it did mention something about the injectors on the screen which i saw with my own eyes. I have done everything from coils, spark plugs and fuel injector cleaner and still nothing. I've read somewhere on b8 forum with the 4.2 engine where audi owner where facing same issue where everything was replaced and nothing fixed it until replacing 8x injectors, and were also faced with changing to new cat because the fuel messed up the cats. Only thing they didnt mention were hard starts. sometime engine will crank and rev up under 1000rpm and then engine died. I would have to recrank and then will fire right up.
Also, it didn't help that the previous guy had 4 different type spark plugs installed.
#12
AudiWorld Member
Any updates on getting this particular issue resolved? Have your changed out the coil harness? I had a misfire on 1,3,4,and seven and to test my theory, i replaced the harness for each coil on cylinder 7 side and i no longer get the misfire on that one. I still get the misfires on 1,3 and 4 but I am going to change them out tonight as well.
Also, it didn't help that the previous guy had 4 different type spark plugs installed.
Also, it didn't help that the previous guy had 4 different type spark plugs installed.
I have the same problem as you, any updates? I'm leaning towards injectors.
#13
I just replaced all 8x injectors yesterday, everything seems good for now, lets give it some time, maybe a couple of days. i will keep you guys updated. By the way i bought them at advance auto parts.
Whats your exact problem/symptoms?
Whats your exact problem/symptoms?
#14
#15
AudiWorld Member
#16
I took them out and with a rigged setup, I ran fuel injector cleaner as I pulsated 12v to them. At first some of them just had a mist of the cleaner come out then three distinct streams.However, you could be right about the electronic side for the computer side of things.
#17
Did this resolve your issue? Having the same issues. My mechanic has already replaced 2 injectors.
#18
#19
#20
I'm not 100% sure. I was working with my mechanic. but if i remember correctly it was 'fuel sensor/pressure error'. On what I was experiencing after cleaning values and replacing all injectors, it was still running a little sluggish. The check engine and EPC light would come, even after resetting it. But if i turned off/on the car. The EPC would go off.
After replacing the driver side high pressure pump. All the problems stopped. As of 2-24-18, car is running great.
Hope this helps.
After replacing the driver side high pressure pump. All the problems stopped. As of 2-24-18, car is running great.
Hope this helps.