W164 Engine Cylinder 6 Misfiring
11-18-2015, 01:30 AM
#1
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ML 280 W164 model
W164 Engine Cylinder 6 Misfiring
I have ML280 diesel W164 model with 642.940 engine. i recently changed the engine. It has never been the same since. I actually have not yet used it. Its vibrating heavily on idling. I have changed injectors it has changed.
After plugging it in it says cylinder 6 is misfiring. What could be the problem and the solution.
After plugging it in it says cylinder 6 is misfiring. What could be the problem and the solution.
11-18-2015, 02:54 AM
#2
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This is only Generic advice
Was the engine doing it before it went in?
did you do a compression test on the motor before it went in?
Have you done the quick things like checking the wiring harness to injectors? (especially to 6)?
Was the engine doing it before it went in?
did you do a compression test on the motor before it went in?
Have you done the quick things like checking the wiring harness to injectors? (especially to 6)?
11-18-2015, 04:22 AM
#3
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Do an compression test, might be cyl.head gasket.
11-18-2015, 06:20 AM
#4
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Just had the thought that if the computer knows its not firing on 6, could that indicate that it is more to do with the injector (or wiring/fuel supply etc to the injector).
I don't know of a sensor would tell the computer it had injected etc on 6, but the compression etc was low and it hadnt ignited properly. At least down to a cylinder assigned to fault.
Also does the symptom go at slightly higher engine speeds?
I don't know of a sensor would tell the computer it had injected etc on 6, but the compression etc was low and it hadnt ignited properly. At least down to a cylinder assigned to fault.
Also does the symptom go at slightly higher engine speeds?
11-18-2015, 07:38 AM
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ML 280 W164 model
The misfiring can be felt at idling. but when driving nothing can be felt. It was not doing this before engine change. we have done the compression test using the scanner. Thest results say an RPM difference of 27 rpm was detected.
values
cylinder 1 .................135min-1
cylinder 2 .................145min-1
cylinder 3 .................146min-1
cylinder 4 .................142min-1
cylinder 5 .................143min-1
cylinder 6 .................162min-1
I have just put in new injectors as well.
values
cylinder 1 .................135min-1
cylinder 2 .................145min-1
cylinder 3 .................146min-1
cylinder 4 .................142min-1
cylinder 5 .................143min-1
cylinder 6 .................162min-1
I have just put in new injectors as well.
11-19-2015, 11:17 PM
#6
Senior Member
I am a bit confused with those figures.
A compression test would have been done with a compression tester through the injector holes typically. Should be in PSI/BAR/Kpa etc
cant see how rpm can be different between cylinders - are they ml/min readings of diesel or something?
Have you driven the car much after the motor change?
I know I had a big truck (12ton) which missed on idle but evened out on running - eventually healed itself with injector cleaner in fuel (but you have new injectors) so doubt that will help you
A compression test would have been done with a compression tester through the injector holes typically. Should be in PSI/BAR/Kpa etc
cant see how rpm can be different between cylinders - are they ml/min readings of diesel or something?
Have you driven the car much after the motor change?
I know I had a big truck (12ton) which missed on idle but evened out on running - eventually healed itself with injector cleaner in fuel (but you have new injectors) so doubt that will help you
