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Boater
01-26-2013, 01:16 PM
Finally got my '96 312D started today, the battery that was fine before I changed the piston rings just wasn't cutting it in this cold weather, fortunately my 'leisure' battery is actually a starting battery (with higher CCA than the old one) and after priming the fuel system it didn't take long to get her fired up.

Right away I noticed I was getting more smoke than before I did the work, however since I have done a near complete rebuild the timing will need adjustment. I plugged in carsoft using the T30 (which seems to work more reliably than my other laptop), deleted old codes and re-read the DFI module.

The only error I get is:
P1352 Needle moving sensor
Verify the tension at the needle moving sensor

Which we have discussed a little before:
http://sprinter-source.com/forum/showthread.php?t=23219&highlight=needle+sensor
But I never did quite find/work out what I need to do to check the sensor output.

I'm going back out to try and check the cables (if I can find the other ends) but would appreciate a heads up on how check the sensor if anyone knows?
Also anyone know if these sensors can be be repaired/rebuilt?

Without a signal the ECU won't know how to adjust the timing and I still can't find the exact procedure for fine tuning it mechanically.

Jim

talkinghorse43
01-26-2013, 02:12 PM
Is the misfire gone?

Boater
01-26-2013, 06:10 PM
I wish I could tell!

It was smoking too much to run for long but there still seemed to be a rhythm to the exhaust, however I am really wondering if this might be normal for this engine.
After I rebuilt it I did a cold leakdown test and all 5 cylinders were within 5% of each other which is OK and better than the warm leakdown test that convinced me to do the rings. I am happy with the compression now.

I decided to test the sensor wiring by trial and error, luckily the wires are connected to pins 1 & 4 of the ECU connector so it didn't take as long as I expected - the bad news is both showed minimal resistance (analogue meter read approx 0 in each case) so it's not looking like a cabling problem.
The wires go into the injector right next to the leak off banjo bolt and are vulnerable to damage doing the bolt up, so I suspect the wires are damaged/pulled off right at the injector end. I am going to contact my Bosch dealer and see if they can check/repair the sensor or give me a price for a replacement injector.

Tomorrow I think I will try adjusting the pump by trial and error, I'm sure I can find a point where it smokes less than it is now.

Boater
01-27-2013, 02:23 PM
Is the misfire gone?

It started to rain as I was taking this - I never realised transferring video from my phone to my computer would be so much hassle! Pretty difficult to see smoke today but it is still there.

Link to video (http://youtu.be/owLyRE2md08)
(how do you embed the video?)

Looks like the rain has gone off so I'm going out to make a timing adjustment....

Boater
01-27-2013, 06:56 PM
I was able to turn the adjuster 3 turns counterclockwise and at which point I reached the limit of the slots in the pump mount and the van wasn't going to start. I then got 5 turns CW past my start point which looks about the middle of the mounting slots and again the van wasn't keen on starting and seemed to be belching black smoke. My notes suggested that 1 turn CW had been about the best so I reset the adjuster to that and packed up, it didn't actually seem quite as good as before but it was getting too dark and cold to do any more but I reckon I must be within about half a turn now.

I'll have to see what the bosch guys say about options for the needle sensor, I'm hoping the smoke is mainly due to it being cold but I may warm the engine up at some point and do another compression and/or leakdown test on it for my own sanity.