[Hammy229]

Well I'm still weirded out. I unplugged the extention harness to the optical sensor and the the truck.would rum but not idle ....so I unplugged the cps and truck started and is currently idling great. So I plugged the cps back in and no change in idel ....only thing is I still have delayed throttle when in gear ....its better than before...and it startes to build rpm but it is very delayed......im going on a quick test drive in hopes I can make it home to see how it acts .
Only code now is dtc 19 from.me unplugging the cps then plugging it back in

 

[Hammy229]

I would change out that CPS ( AC/Delco brand)

Yeah I couldn't find one on short notice but I think I'll go to the local chevy dealer that's about the only place I can think to find one. The truck seemed ro run fine other than it seems to lack some of the power it had before ...and I have a slight white haze fron the tail pipe like it's unburnt fuel ...could this mean my pump needing to be turned one way or the other.

Also if it ain't one thing it's another, yep those are starter bolts ...thank God the block didn't crack just the stud for the bracket, and yes I did have my bracket on . I believe just from all the cranking lately the bolts just got loose enough for it to move around. But the good news is the broken pieces came out easy.

 

[Hammy229]

You may have to order it online. Try searching eBay for NOS CPS

I'll give that a try thanks!

 

[Hammy229]

It sounds to me like besides from needing new starter bolts now you just need to properly set the pump timing. Do you have the gmtd software and cable?

No I do not. I did a little bit of research about one but haven't gotten that far yet

 

[Hammy229]

i have a tech 2 now but 1 of my old laptops has the gmtd software. If you need it I can send it to you. You would just have to buy the usb to obd1 cable

My wife has a laptop that will work I will just have to find a cable and get the software.
Is the best place to get it the engh guys? Also any good places to get a cable ...will any USB to obd1 cable work?

 

[Hammy229]

My batteries are not happy with me after all the cranking here lately...after charging most the day yesterday and today they finally held up enough. So the symptoms now are with the cps plugged in the truck will white smoke like crazy with erattic idel ...with it unplugged it takes longer to start (obviously) but once start it runs fine. Now I know I need to do the tdco relearn regardless but I guess my question is will that solve the issue or could my "new" cps be bad . I have a Ntk one on order and I'm still looking for an acdelco one but they seem hard to find

 

[Hammy229]

I know it's been a minute.. but finally thanks to the snail mail I got my all cable today.

But this issue is with the cps plugged in I can't get the truck.to.run long enough to do a TDC relearn unless my high idle switch is on.
But when I unplug the cps the truck will run fine then I plug the cps in clear the code then do the relearn and while it's doing the relearn it white smokes and dies before it can finish ....any ideas what to.try?

 

[Hammy229]

So I turned my pump.to.the drivers side and the idle smothed out but here is what I have after the relearn

I tried moving the pump more but the tdco staye at -2.02 . Any movement to the passenger side and the truck will not idle and has white smoke like crazy

 

[Hammy229]

Also I now have code 88 tdc offset error that keeps coming back after clearing

 

[Hammy229]

So I got the pump as close to +3.5 as possible. While in time set the reading is pretty erattic. The problem is I can't keep it running unless my high idle switch is on (1060 I believe). So when I do the relearn while in high idle the tdco jumps around and ended around + .86.
With lots of white smoke and still won't idle.
So I bummed the pump allitle to close to + 5
Same situation with the high idle and after relearn tdco was -1.94 but still smoke (not as much) but still won't idle. I have tried my ntk cps and standard motor cps. For the life of me I cannot find an acdelco ( haven't called the stealership yet) could this be the issue ..or is my new pump trash.

On a side note if I advance pump to like 10 in time set mode it starts great and runs great with no advanced rattle. But tdco is -2.02 or more cause it doesn't fluctuate.

I'm considering putting my old pump.back on just to see if it was my cps all.along ....or just if the dang thing will time right.

 

[Hammy229]

So I'm just all out confused at this point
Finally truck will run and idle without high idle switch on.

What has happened is I had the pump around 4.5 to 3.5 and did a relearn and got a tdco of -1.06 but truck would still not idle . So i turned the the pump advanced (to drivers side) to and average of 8.6 on actual. I DID NOT redo a tdco relearn so tdco is still -1.06 and truck is running and idling fine ...only issue is some what harder starting but it was probably its 50th start today so batteries might be getting week. But I'm afraid if I do a relearn again the tdco will go past -2.02 and I will get code 88 again.

I'm going to let it cool and see how it starts and see what happens I guess. But I still really don't have any answers to anything at this point....

 

[Hammy229]

Well after alot of failed attempts I decided to just put the old pump back in. Took me about an hour and a half.

So I put the old pump back exactly how it was before I took it out . Bleed the air and truck started way better than it ever did with the "new" pump .
Then i put the ntk cps back in due to the standard motor one was not reading anything.
Truck starts fine and I had to adjust the pump just alittle from where it was I have tdco around -.97.

All seems well, no codes. The only issue now it's I have a slight haze of white while driving. This along with white smoke on start up (more than normal) makes me think one of my also "new" injectors might be bad ...or I knocked something loose when messing with the pump . And one of the injectors keeps popping off the return line. Is this also a symptom of bad injector, or plugged return line somewhere?

All in all the thing runs fine now like I said other that the white haze . Wich leaves me not wanting to drive it still..

 

[Hammy229]

Glad to hear it’s running better with the old pump👍I’ve never seen these injectors cause a return hose to pop off.I might have overlooked it in this thread whether or not if you replaced the injector return hoses?

Did you replace the injectors in your truck at some point?I reread this thread but don’t see any mention of it unless I again skipped over it.

I guess long story short . I replaced headgaskets and reringed. And in doing so yes I replaced the injectors because of not knowing their age(I bout truck with blown head gasket) after rebuild everything was good for 300 miles until this injection pump fiasco.
The injectors were the (marine) from accurate diesel. I don't think the are Bosch though and I did do new return lines , the push on kinds. It's only coming off the one injector . Could just be a bad piece of line I guess.

 

[Hammy229]

I know it's been a while but just a quick update . I replaced the injectors with bosh ones off of rock auto and redid the return lines. Everything seems to be peachy now . All in all I'm thinking the original problem was just the crank sensor. I still have some white smoke on startup but I belive replacing the coolant sensor on the crossover will help that.( no smoke when unplugged)
Thanks again to anyone who helped and gave advice!

Here's a picture too just for fun!

 

[Hammy229]

So, is the NTK CPS in there now?

Yes the ntk cps is in there .....the standard motor one didn't seem to work nearly as good.

For comparison the standard motor cps was around $25 and the NTK was around $70

 

[Hammy229]

It looks like the NTK is the ACDelco replacement.

I would agree
I for the life of me could not find a true Acdelco other than one dieselolds found on ebay. I didn't try a dealership either but I'm sure their price would of been more if they had one.