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Hummer p0216

ron993 said:
on the DS4 pump is there any adjusting the pump physically or is all done via the Tech2 computer
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quadstar87 said:
You have to physically move the pump to set base timing/TDCO. It's a mechanical setting that gets learned into the computer.
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That is where the scanner is needed.
You loosen the three 12 point 15mm nuts then clock the IP one way or the other.
First hook the scanner to the truck, clear any codes, set it up so when the engine starts it goes into timing learn mode.
If the enjun dies, then clock the top of the IP towards the left side of the vehicle. about two mm. again try starting the enjun, if it again dies then clock it another two mm.
Note: when the engine starts, a code will set, do not be concerned, it is just telling You that it is in timing learn mode.
I think I read that the timing could be as high as -1.5 on the timing off set.
Dont quote Me on that though as I do not want to see anyone burn holes in pistons due to the timing being advanced too far.
 
On OBD1 the timing can't go past -2.02 or it will set a code and can be difficult to get it out of that code. Not so much on OBD2. -1.94 is considered to be the most advance that show any performance gains and that is negligible IMO. Factory specs are -.35 to -.75. you also need to be above 170* engine temperature to do the relearn.
 
ron993 said:
I talked to a mechanic friend today and it looks like his snap on scanner may be able to set/check the timing. I am going to take the truck to him on friday to try it
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The left side 12 point nut is a real tough one to get a wrench onto. I made a wrench with several wrenches, cut them and welded them together.
If I can get a ratcheting box end wrench with the forward/reverse lever, I`m going to rebuild this wrench and incorporate the ratcheting box end onto it.
IMG_3421.jpg
 
ron993 said:
I bought the wrenches to help do the job

https://www.google.com/url?sa=t&sou...BPEQFgiAATAA&usg=AOvVaw1tJWQixUGN5XJQjacMKtgN
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Your all set to go then.
I did take the truck to the college here, they had Snap On scanners, dont remember the model name, it woul not do the timing off set function. I guess there are some Snap On ones out there that will.

ak diesel driver said:
I have the ratchet on my homemade one. It's really nice to be able to wiggle it back an forth one click at a time.
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YUP, that is about all the room there is. I never tried dismounting the A/C pump though.
 
Scan "Desired Timing" "Actual Timing" and "TDCO or Top Dead Center Offset" before you change anything. See if Desired and Actual match and note the TDCO value. Then, put it into re-learn and see if the TDCO value learns differently. If the pump needs moved, you'll know after it tries to learn. It may learn in spec, may not. ECT needs to be 170*F+ for a learn.
 
I ordered a new AC Delco crankshaft sensor and went to swap out the autozone CSP last night before the rain and realized the CSP cannot be removed with the power steering pump in place. I was able to pull it out enough to to look at the part number on the part itself and it matches the AC Delco, same part number, both manufactured in Mexico. I am hoping to go to the mechanic today to see what he can do for me
 
When I changed the CPS on My truck, I had the timing cover off.
After putting it all back together and looking at it, I thought if I ever would need to change the CPS, I would grind away part of the PS bracket, just enough to make a relief to get the job done.
 
It's not really that hard to move the PS pump out of the way. Release tension on the serpentine belt and pull a couple of bolts and it's off and can be moved over. The part #'s may be the same and both made in Mexico, but all AutoZone electrical parts are crap and there are too many instances of them failing out of the box new. On things like the CPS and other sensors, go genuine ACDelco.
 
Husker6.5 said:
It's not really that hard to move the PS pump out of the way. Release tension on the serpentine belt and pull a couple of bolts and it's off and can be moved over. The part #'s may be the same and both made in Mexico, but all AutoZone electrical parts are crap and there are too many instances of them failing out of the box new. On things like the CPS and other sensors, go genuine ACDelco.
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That is very true.
I just figured with the air compressor setting right there, a die grinder in the tool box and an alunamum carbide cutting bit, probably be a quick and easy task. LOLOLOL
 
So on top of everything else the power steering pump is leaking. It is a new pump, but I guess when i installed the reservoir can the o-ring must have rolled. Is the bracket that goes from the PS pump to the block needed?
 
ron993 said:
So on top of everything else the power steering pump is leaking. It is a new pump, but I guess when i installed the reservoir can the o-ring must have rolled. Is the bracket that goes from the PS pump to the block needed?
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Generally brackets are needed. Diesels pose Extreme vibrations to the point that missing a rear support for an alternator will snap the case clean in half. Just saying don't take shortcuts and leave parts off... Your starter brace mid-block is on correct? - without it the starter can snap the ear of the block clean off! (Yeah these are the two bitch bolts on the engine: starter and PS pump mid block... )
 
Sux about factory starter, when that 900 pound elephant dies, install a powremaster. In fact you can buy 2 powermasters, new starter bolts, and the different brace all for less than the price of 1 prestolite, and the 2 new ones will weigh less combined!
You can post pics about power steering pump- there are 2 different ones used in hummers I have seen so far and maybe you have something extra? But I am likely to agree with WW about needing the bracket.

Knowing that you need to take it in to have it timed, I would do that first before trying another cps. I can't remember at the moment- did you try unplugging the optic sensor? if it w/ runs with optic unplugged then the cps is working. It will be hard to start, but will start and run. If it fails to start then time to move over the steering pump to swap the cps.
 
Took it to the mechanic this morning and TDC could not be adjusted, the CPS is bad and with the snow we had last night neither of us wanted to crawl under the truck to work on getting the CPS changed out. Gonna wait till the new power steering pump gets here next week and will change it out then and take it back to him.
 
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