Rough Idle due to injection quantity issue?

k_harley

Vendor , w/Business number
Joined
Oct 26, 2006
Location
Lowell, MA
TDI
2006 Jetta TDI, 2005 Audi S4, 1997 Audi A4 Race car, 2004 Passat TDI 6MT 4motion
So this AHU engine vibrates badly at idle, much smoother at 1100 rpms with a little throttle.

I had the injectors rebuilt by drivbiwire, they were breaking too low, otherwise they were ok.

In block 8 one of the values was 0 mg/stroke while the others were clearly higher at 13 or something, dont remember exactly. Then at 1100 rpms the value got higher, but still much lower than the others.

Should I assume that one injector is not pushing fuel at idle?

Thanks for the help in advnace!
 

kjanracing

Vendor , w/Business number
Joined
Oct 20, 2008
Location
Westminster, Colorado
TDI
99 jetta IV
Possibly. Is the engine sound-compression ok? Crack a line at each injector at idle and see which cylinder is dead one. Is any fuel coming out of that line? Try swapping the dead injector with one that has an rpm drop to see if it follows the injector. Maybe you have a bad injector. Can you get them pop-tested?
Kurt
 

k_harley

Vendor , w/Business number
Joined
Oct 26, 2006
Location
Lowell, MA
TDI
2006 Jetta TDI, 2005 Audi S4, 1997 Audi A4 Race car, 2004 Passat TDI 6MT 4motion
OK, so I was over anylizing it. It was a problem with the motor mounts not being balanced, putting too much weight on one of them which made it shake like a.....welll, you can imagine it.

Thanks
 

dr.diesle

Veteran Member
Joined
Mar 5, 2008
Location
Calgary
TDI
92 golf tdi/01 golf tdi /02 golf tdi/04 jetta wagon tdi/vanagon westy tdi
Why did they rid the oil filled mounts oh yeah just for this reason ...
 
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