[ltd1963]

I just got a Tech 1 A from ebay and went to check my IP timing and TDCO. Around a year and 1/2 ago I installed phazer gears and never got the timing set or TDCO because I dont like paying the dealers for 1 time changes when I could do it all I want if I had the tool.

Turns out my tech 1 says

Water temp
180*

Injector Pump Timing
Des=9.5*
Measured= 9.1 to 10*
(way off from what I want 3.5)

Injector pulse width
1.67 ms

TDCO
+1.94*
(way off from what I want -1.94)

When I try to do a Injector Pump Timing learn the Yukon dies.

My question is what way would you move the pump?

 

[qwomack]

Rotate the top of the pump towards the drivers side.

 

[w_huisman]

Rotate the top of the pump towards the drivers side.

.....about 1.5mm

 

[ltd1963]

Thanks Ill try it this weekend.

 

[ltd1963]

Well it took a few tries but I got her to

IP timming 3.5

TDCO -1.94

I dont know if to got any more HP out of her but the pedal responce seemed crisper. No trouble over the weekend but when I started her this morning the temp was around 5* and I think I set a code. Ill check it at lunch and see what it says.

Thanks for the advice.

 

[gmctd]

So, help me out, here - you scanned the PCM with the Tech1 to find you had the much-desired performance timing and TDCO settings of -1.94deg, and you're attempting to change them, for what reason?

 

[DavidPhillips]

It was +1.94

 

[gmctd]

Ya gotta watch Tech1 data display - shoulda been throwing a code if really +1.94

BTW - did you get your GMTDScanTech to read Desired Timing at some value other than 0?

What does that Actual +3.5deg look like in TIMESET?

 

[ltd1963]

When I checked for a code at lunch, the tech 1 showed no current codes and had a stored or history of code 88. I think that was left over from the previous attempts when I tried to set the TDCO when I didnt understand what I was doing. When I did it over the weekend all went well so I think im good. Ill check it again tonight after I get the Yukon warmed up.

I thought it should have had a code when I was running it at +1.94 but there was not one. I ran it like that for over a year. No codes. I had to move the pump 3 to 4 mm's to the drivers side to get to -1.94

The IP timming set if I recall was des of 0 and actual varried between 4.? and 3.?. Never steady for very long. Ill check that again also.

 

[gmctd]

Read this for information.........
http://dieselplace.com/forum/showthread.php?t=126871&highlight=timeset+TDCO+LEARN