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View Full Version : Getting Closer....still a DTC 88



WRB Diesel
02-18-2008, 08:41
After smoking out the entire neighborhood with white smoke waiting for the engine to come to temp, I ran the TDCO procedure (94 suburban) and things started sounding and feeling alot better. The offset was 2.02, Desired and Actual timing are around 8.5.
Problems are :
still setting off code 88 and sometimes 98 (#8), 97(#1)
and still some smoke and slight engine vibration.
I guess my question is, if and when I back off the IP a bit to get closer 1.5 offset will the codes go away or I am still doing something wrong. Following some of the posts sounds like people will run 2.02 for performance, is this offset so far advanced that the PCM will always pull the TDC offset DTC.
Thanks for the help.
Aryn

DmaxMaverick
02-18-2008, 12:05
2.02 is much too retarded. As you advance into the acceptable range, it should run better, smoke less, and the code should go away, as you approach +1 to negative. The desired/actual is showing you the pump is responding well to PCM timing commands, which is good. Now, you are out of range, and it will set the code. The smoke is typical of retarded timing, but you may have other issues as well if it's only at a cold startup.

WRB Diesel
02-19-2008, 16:14
Whos more retarded? the truck or myself? considering I didn't recognize that the TDC was +2.02 and not -2.02 I would say myself.

thanks for the help

JoeX87000031
03-01-2008, 04:07
What is the TDCO that you speak of. Do you need special tools to do it? I gather that its a way to time it, but if you could let me know a few juicy details It would be great. It would be awesome if there is some pin somewhere you could hook your normal timing light to so that I can check the timing myself. Thank you all for dealing with all of my annoying questions. Take care

DmaxMaverick
03-01-2008, 09:04
TDCO = Top Dead Center Offset

It's the electronic timing adjustment, offset from the physical pump position timing. A scanner or PC program can be used to set it, or can be done with a KOKO (Key On - Key Off) learn procedure (no timing "light" necessary). Search for it in this forum (lots of current input).

You can find more acronym info HERE (http://www.thedieselpageforums.com/tdpforum/showthread.php?t=20598). Ask questions or add them as necessary on that thread.