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Old 08-05-2019, 01:46 PM
TCRIX5 TCRIX5 is offline
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Join Date: Jul 2019
Location: RI
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The link above should get you to plot of duty cycle bank 1(2) vs RPM. Green and blue graph lines look almost the same color so Bank 2 duty cycle is the line with the large down spike.

Things I've done to date:
40k miles ago valve stem seals - no smoke and still works like it should.
Within last 1K -
[Bank 1] check timing - intake cam was off by about .5 cm. Set timing replaced vanos solenoids and camshaft sensors. No oil in eccentric shaft sensor connector so I didn't replace. I chose to replace solenoids due to finding non OEM parts installed (discussion for another time). Cleared faults, test drive for about 100 miles result being no faults stored but it doesn't idle as it should. I performed vanos duty cycle test again and it hasn't changed, essentially the same as the graph I provided the link to. At this point I determined that my assessment of bank 1 performance was wrong and that in fact bank 2 is the problem.
[Bank 2] following above I pulled the vanos for both inlet and exhaust and find more junk from china (search the part number and I could buy them for 14$ each, again different discussion). Swap in two used but clean and functioning solenoids with new software and perform road rest, same result as before and the graphs look the same. Into the bank I go, in the process of removing the cover I f'd the eccentric shaft (my fault, sometimes I suck). But i did find the timing to be spot on and the camshafts look perfect, intermediate levers installed correctly, no blocked oil passages or leaking check valves.

I suspect one of the following but don't know for certain:
(1) Bank 2 vanos adjustment unit is stuck, they were locked when I checked the timing. That doesn't mean one or the other will move when required.
(2) DME has a fault that does not set the CEL or record a fault. Unlikely, but if sending the thing out for R/R is the right answer, then off it goes. I don't have data to support, but again I don't know.
(3) Bad crank bearings. I'm pretty religious with oil and filter changes. The damn thing runs great and is smooth like new without vanos.

Last edited by TCRIX5; 08-05-2019 at 03:09 PM.
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