Timing 6.5 TD

[CapnAmerica]

Question for a more-experienced person...

I replaced my injection pump; all OK, nearly as I can tell. The procedure tells me I need to command the "time set" to zero. Desired timing is now in the 9deg rangs after warmup, and nothing I can do will change the Actual Timing.

I have an AutoTap scanner, which interfaces with my laptop--seemed like a nice toy, and SHOULD (so I thought) perform the functions of the Tech 2. Apparently one thing it will NOT do is this Time Set=0 procedure, unless someine knows more than I. AutoTap folks are too busy to talk right now.

Do I need the Tech 2 or equal Snap-On for this step? Are there any other alternatives for this?

I can read and set the TDC offset with no problems; however, without setting the Desired=0, the TDC offset apparently is goofy every time. I made a pump adjustment tool and can rotate the pump anywhere I want to.

Thanks for any input I can beg!

Charlie Jones
Hendersonville, TN
1996 GMC Sub with 164,000 and not much optimization yet.

[jjbouwens]

If you mean the TDC offset my 1996 service manual says the following:
1 Engine must be warm i.e not less than 170F
2.Ignition "on" engine "off"
3.clear all TDC's
4.Ignition "on" engine "off" and hold accelerator down for at least 45 seconds. This clears the TDC offset fromthe PCm
5.Turn ignition "off" for 30 seconds-this powers the pcm down
6.Ignition "on" engine "off". Now with your scan tool you should verify the the TDC offset is at 0(zero)
6. Start and idle engine
7. Check temperature at least 170F
8. As soon as the temp has reached 170F and the engine speed is below 1500 rpm the PCM learns the new TDC offset it should be between -.25 and -.75. If not you have to rotate the pump but this is another story.
Good Luck
-----------------------------
96 Brave Camper with F engine P32 chassis currently waiting since 3 months for parts from the USA after a Spanish truck driver successfully shortened the Brave up front while on the parking lot.
:mad:

[CapnAmerica]

Yep, I have that info. TDC offset is the easy part.

To properly set the timing itself, I need to reset the Desired Timing to 0, and my AutoTap laptop scanner doesn't seem up to the task. What is happening is the Desired Timing is around 9 deg advanced, and no amount of rotating (and Hoo Boy if you go to far you can fog the neighborhood for mosquitoes!!!) will get the Actual Timing into the spec range (avg. 3.5 deg).

Looks like it's Diesel Doctor for me, at least for setting the desired Timing to 0. The AutoTap works just fine for chacking and setting the TDC Offset and checking the Actual Timing.

Thanks!

Charlie Jones

[CapnAmerica]

Timing Update--Visited a diesel doctor in SC. He used his Real Analyzer to command the time set to 0. At that moment, while the analyzer is in command of the truck, the reading for the Actual timing is taken; it was almost precisely 3.5 deg. average. I then tried the TDC offset again--came in at +2.4 DEG. Rotated pump to the passenger side, and got near +.5 or so. The TINIEST movement of the pump after that threw the system into an uproar, and the relearned offset was 5,600 deg (give or take a few hundred). However, I think this is a red herring, because it seems to run fine.

Any help out there? Hopefully short of buying a new ECM? I AM a retired cheapskate, or cheapskate retiree--take your pick--and would like to avoid further grand expenditures if possible...

Thanks!

Charlie Jones
a.k.a. Capn America in TN

[DmaxMaverick]

TTT for Joe Bleaux