GMTD scan tech

[Goose57]

Maybe this will help? From the 96 manual but, ODB1 procedures folks are explaining look to be tge same View attachment 90025View attachment 90026

I can print page #2 but can’t print page #1. I believe because the blue + sign is cropped too much. Sorry for the trouble could you post the pages so I can print them. It will be a big help. Thanks.

 

[MrMarty51]

I can print page #2 but can’t print page #1. I believe because the blue + sign is cropped too much. Sorry for the trouble could you post the pages so I can print them. It will be a big help. Thanks.

Are You working from a computer to view the pics ?
Right click, save to photos.
Go to photos the should be able to size it to fit the printer, or it probably would just print right up.
From phone, tap on page You want to print then when it appears, hold on it, save to pics, now print frrom the pics.
If it wont give option to save to pics, take a screen shot, then save to pics, then print.

 

[Paveltolz]

Try this file and see if it'll print.

 

[Goose57]

Thanks guys I’m not only learning about these diesels also about computers Thanks again.

 

[Goose57]

I’m going to go out to set the timing tomorrow ( w/ 97’ timing procedures ) after a good night sleep so that I’m thinking clearly
I’m going to check and adjust IP timing in the TDC Time Set Test to Measured Ing. Time 3.5. Then attempt TDC Offset. Warm engine up or use the coolant fooler , check and clear codes , w/ KOEO hold the accelerator in WOT for 45 sec. then turn key off for 30sec. Warm engine back up 170 deg. or still use coolant fooler. Then check to see if TDC Offset learned -0.25 to 0.75 deg.( my truck is a 95’ .0 to -50 deg.). Or does it make a difference? If the Stupid thing didn’t learn I will have to adjust the IP again
but won’t that mess up the 3.5 deg. IP timing?. Now the Tech2 I have has a TDC Offset Learn and the 95’ manual says with using the Tech1 activate the TDC Offset Learn. Does my PCM have the ability to do a TDC Offset learn? Could I get some input? Or am I over thinking this again? Thanks guys.

 

[dbrannon79]

it should be the same procedure using the tech 2. a 95 model will require the tech 2 or 1 to trigger the learn.

 

[Goose57]

Finally got the Time set at around 3.5 and TDC Offset Learn -35 to -44. Still misses and dies when in gear. No currant DTC,s. But does have DTC,s in history cylinder balance #91 through #98. Assuming bad new AC Delco injectors. What do you guys think? Here’s some videos on how rough it runs

 

[dbrannon79]

Try doing an injector cut out test and see if you can isolate which one seems weak or not working. does the exhaust smoke smell like un-burnt diesel?

side note on videos, turn you phone sideways for full screen. if you can, do a full video of it idling while you cut off each injector one by one while watching the engine shake. maybe it will help us diagnose what is going on. you might even do a video on a cold startup watching both the engine and tail pipe as well.

do you still have your old injectors? if not, when we can possibly isolate which one might be the issue we can switch that injector over to a different cylinder and see if it follows or the miss stays with the same cylinder.

 

[Goose57]

Try doing an injector cut out test and see if you can isolate which one seems weak or not working. does the exhaust smoke smell like un-burnt diesel?

side note on videos, turn you phone sideways for full screen. if you can, do a full video of it idling while you cut off each injector one by one while watching the engine shake. maybe it will help us diagnose what is going on. you might even do a video on a cold startup watching both the engine and tail pipe as well.

do you still have your old injectors? if not, when we can possibly isolate which one might be the issue we can switch that injector over to a different cylinder and see if it follows or the miss stays with the same cylinder.

Sorry my bad again. The dtc,s in the history were only 91,94,95,96 and 97 not 91 through 98 cylinder balance errors, along w/ dtc. #88 TDC Offset Error, I got them before when I was going through the Time Set and TDC Offset Learn. I’m going to see if dtc,s 91,94,95,96 and 97 come back. I did do the injector cut out test several times in a row. The cylinders I cut out were not consistent each time I ran through the test. Each time I ran trough the test one cylinder was bad and the next time it was good. It’s not pointing to one cylinder. Could it still be a timing issue? If so wouldn’t it throw an dtc? I didn’t watch the clear line for air while I was doing the test. Air? What I’m afraid of is having all the injectors checked out and that not being the problem. I wish I would have had the new ones checked. I didn’t smell the exhaust but I can tell you there is black soot on the concrete where the exhaust hose was lying. I will definitely send better videos as you suggested. No I do not have the old injectors. If I can be sure it is the injectors I’ll yank them out and have them tested.

 

[dbrannon79]

I know you probably mentioned it before but I forgot. what is the condition of your IP? I assume you are using the one from your old engine and it ran fine before the engine replacement? you can also do the injector cut out while trying to hold the idle up a little too. just like checking to a fouled spark plug on a gasser, sometimes it's more pronounced when idled up some while pulling plug wires, in your case turning off injectors.

 

[Goose57]

I know you probably mentioned it before but I forgot. what is the condition of your IP? I assume you are using the one from your old engine and it ran fine before the engine replacement? you can also do the injector cut out while trying to hold the idle up a little too. just like checking to a fouled spark plug on a gasser, sometimes it's more pronounced when idled up some while pulling plug wires, in your case turning off injectors.

Sorry I have it in my signature as LP instead of IP. I’ll have it edit it. It’s a new DS4.

 

[jrsavoie]

Sorry I have it in my signature as LP instead of IP. I’ll have it edit it. It’s a new DS4.

Where did you source it?

It's hard to find good parts.

Is it a rebuilt ?

Seriously, depending on where you got it, I would take it to be tested along with getting your injectors tested balanced.

Neither may have anything to do with your issue. But they would be ruled out.

It could be a time saver or even an engine saver in the long run.

 

[Goose57]

Where did you source it?

It's hard to find good parts.

Is it a rebuilt ?

Seriously, depending on where you got it, I would take it to be tested along with getting your injectors tested balanced.

Neither may have anything to do with your issue. But they would be ruled out.

It could be a time saver or even an engine saver in the long run.

I got the rebuilt IP from Quadstar couldn’t get a new one. You think it could be a bad IP? I did not get any IP related codes. Had no trouble doing the Time Set and TDC Offset Learn. The only codes were in the history, cylinder balance codes and looks to be the same 4 Or 5 cylinder codes. I’m going to post some start up and run
Videos. Thanks for the input.

 

[Goose57]

Ok guys I made some videos of my truck on start up and run. Also there are a couple cylinder balance tests. I did not smell any diesel fuel at the tailpipe. There is no way I could hold the RPM,s steady off idle during the cylinder balance test. Ok there is 1 cold start video had to step on the accelerator to keep it running. 2 tailpipe videos, engine sounds different in each video. And 2 cylinder balance test videos, the cylinders didn’t respond consistently (the same) in each video. It didn’t point to one cylinder. I believe at the least I should do a compression test then have the injectors tested and balanced. Maybe have the rebuilt IP checked. I look d at all the DS4 Ip manuals though to myself if it was an electronic failure it would trigger a code? there is also the mechanical side of the pump that could be the failure. Very complicated part. All
Opinions greatly appreciated. I was so excited to her it running but not so much now. You tube didn’t let me upload the second cylinder balance test. To many today at the limit. I’ll post it tomorrow

 

[Goose57]

Ok guys I made some videos of my truck on start up and run. Also there are a couple cylinder balance tests. I did not smell any diesel fuel at the tailpipe. There is no way I could hold the RPM,s steady off idle during the cylinder balance test. Ok there is 1 cold start video had to step on the accelerator to keep it running. 2 tailpipe videos, engine sounds different in each video. And 2 cylinder balance test videos, the cylinders didn’t respond consistently (the same) in each video. It didn’t point to one cylinder. I believe at the least I should do a compression test then have the injectors tested and balanced. Maybe have the rebuilt IP checked. I look d at all the DS4 Ip manuals though to myself if it was an electronic failure it would trigger a code? there is also the mechanical side of the pump that could be the failure. Very complicated part. All
Opinions greatly appreciated. I was so excited to her it running but not so much now. You tube didn’t let me upload the second cylinder balance test. To many today at the limit. I’ll post it tomorrow

Don’t know why it was taken down I’ll try again

 

[Goose57]

Ok I’m trying again.

 

[dbrannon79]

Seeing all that black smoke on the first startup and the long crank time is making me think maybe over fueling. the engine seems to be compensating when you do the cutout test as well. mine won't do that! check the clear return line on the IP when you crank like that and make sure there are no air bubbles. you can also crack the injector lines loose on the ones you can get to (drivers side bank since turbo is installed) snug them back up so you can start the engine then while idling slowly loosen one then re-tighten move to the next while watching and listening to the engine. just keep you hands clear as 1900-2000 psi are in those lines. that is a manual test. Just don't loosen them so much so the line comes off shooting diesel all over and use extreme caution.

other things are making sure your return lines from the injectors to the main return is clear and not blocked internally. iirc others have said any slight blockage and the injector won't fire properly.

all in all with no codes and TDC offset within spec it might be worth having the injectors tested and balanced. only other thing I can think of is maybe your PCM is going south. it's not common but can happen. on my 95 truck I was having issues with my turbo wastegate solenoid where GMTDscan's test would not function the solenoid and I kept getting codes for the solenoid when I got on the freeway. replacing the solenoid did nothing. I just so happened to find a PCM out of a 94 truck in the pick a part yard and snagged it up, cost me a whole $15 for it lol. I had it stashed under the seat for a spare.

when I discovered this, I pulled it out and tried it and it fixed the issue. no more code and the functional test on GMTD worked. this was shear luck for me at the time. I don't know if there is a junk yard near your area but it might be worth seeing if you can find one. sice yours is a 95. the PCM from a 94 -95 will work. 93 won't unless it's engine has the electronic IP and a 96 is completely different.

if you find one even if the engine has an EGR, or manual trans, just swap the prom chip from your PCM into the JY one and it should work or at least help rule out this as an issue.

@Will L. @ak diesel driver what are yall's thoughts on the vids and how it runs here? Yall have more knowledge and experience than I do!

 

[dbrannon79]

going back before you replace the engine. remind us what happened and how was it running before it all went down needing the replacement engine. maybe there is a clue in this that would lead to getting this resolved.

there are three main sensors on these engines along with the PMD that can cause engine misses and what not. the CPS (crank position sensor) OP (optic sensor inside the IP) and the CTS (coolant temp sensor)

the engine will run but will give a long cranking session before starting when ether the CPS or OP looses signal, but the engine will not run with both out. check your connections on both along with the wiring for them. the CPS is in the timing cover and will have it's connector up behind the belt tensioner, the OP is the large connector on top of the IP. 94 and 95 from factory had a small black box with and male and female connector. one end went into the IP and then connected into the harness. if that is still there, remove it and connect the harness direct into the IP. that thing is a noise filter and are notorious for causing grief.

the fact you don't have any codes for the CPS or OP says both are working, and the CTS shows normal on the screenshots of you tech 2. it's just odd that you have to crank so long before it starts and all that black smoke bellowing out as you crank. How long are the glow plugs staying on? the delco 60G's will need a little more time than the factory ones. but that new engine should have plenty of compression not to need them in temps over 50 degrees.

 

[Will L.]

You are already hitting all the suggestions I would have here. I am sick right now so deep thought on stuff isn’t gonna work good. I will be coming up with round pegs for square holes right now. Video on that clear ip return line is about the only thing I didn’t see you suggest.

 

[Goose57]

Thanks, the PMD that is on there now is the one on my truck before I changed the motor. It should be good the truck was running fine. I have all new sensors and IP. Also a new upper engine harness from Quadstar. I don’t think I have that noise filter w/ the new harness, I will check. It’s the one that goes over the intake instead of under it. I do have a PMD relocation harness from Leroy’s that was working on the truck before. No sensor codes. No IP related codes. I will check the return lines for blockage. Check the clear line for air when cranking. The GP run time is 6 to 8 seconds. I’ll have to check again. I do cycle the GP,s several times and press on the accelerator to start it. The only DTCs that come back are cylinder balance codes in the history. I believe it’s 4 or 5 cylinders and I believe it’s the same cylinders. I’m going to check again. I’m not opposed to pulling the injectors and having them checked and balanced. Especially since I have the wheel wells off. If is the IP causing rough idle ( it revs up fine) and the smoke why no codes?