1994 Can’t time Set or set TDCO with Tech 2

[Big T]

Here is what I get:


I turn on the command but other than that, not sure what I’m supposed to do with the Tech 2. I moved the pump to the driver’s side, which took the timing down from 8.0 to 5.0. Could use some help here.

 

[ak diesel driver]

From what I remember once the computer sees it that far out of spec it can be a bear to get it out of that mode. Also your in time set and you want that to be 3.5 IIRC after you get that you go to the learn screen and command it to learn via the button that says on

 

[Big T]

Tech 2 says it can’t clear DTC for TDCO from “Controller”. I assume that is the PCM?

The instructions in tech section here say to jump terminals A and B on OBD 1 port, ignition on, press brake pedal and accelerator pedal and hold for 1 minute. Which ones are terminals A and B?:

 

[ak diesel driver]

If you look really closely I believe they are labeled

 

[Big T]

If you look really closely I believe they are labeled

Tried this and they aren’t labeled.

 

[ak diesel driver]

 

[Big T]

View attachment 68703

Thank you. I was doing all sorts of searches here.

 

[Big T]

Jumped it and held the brake and APP down for 1 minute with ignition on and still get:

 

[Big T]

I fabbed an IP adjusting tool from an old boat diesel alternator bracket:



Moved the IP to as close to vertical as I could:

 

[Big T]

It’s no longer setting a TDCO code w/ CEL. I guess We’ll have to live with this.

 

[MrMarty51]

What did the TDC off set come to finally be ?

 

[Big T]

What did the TDC off set come to finally be ?

-2.46, which must be a default #. I am going to try and disconnect the batteries for 10 minutes in hopes of clearing the stored code. I can clear the CEL. Otherwise, I need to find another site with people who can help on this.

 

[Big T]

I will say that it’s sounding like a 6.5 with TDCO set close to -1.94:

 

[MrMarty51]

The codes all have to be cleared before performing the TDCO relearn procedure.

 

[Big T]

The codes all have to be cleared before performing the TDCO relearn procedure.

Well the Tech 2 is not clearing the code from memory. Jumping the A & B terminals did not do it either.

 

[MrMarty51]

Oh my. Disconnecting the batteries for a minute or ten should clear them codes, then start out fresh on the timing relearn.

 

[ak diesel driver]

I would try moving the pump quite a bit to the passenger side and then doing a KOKO

 

[Big T]

Nope, disconnected the batteries while I ran some errands. 088 code is still there, with CEL off.

Jumped A & B again and I get a single flash, followed by 2 flashes. Is that the “12” they speak of in the tech reference?

 

[ak diesel driver]

yes

 

[Big T]

I would try moving the pump quite a bit to the passenger side and then doing a KOKO

It’s a ‘94, so no KOKO.

I’ve already tried moving it to the passenger side “quite a bit” and that is when the CEL a came on with the 088 TDCO code. Before then at least it was showing codes cleared, but it always had that message “not from Control”.