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6.5 running like crap after new IP install

J

JonnyTheKidd

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so i replaced my injection pump. I'm new to diesels. i got the timing close 2.9-3.5. but it is running like crap i bled everything the filter, return lines, injector lines cracked them 1 by 1. the truck was running fine with the old injection pump it was just leaking fuel and filling the valley. i took the new one off putt the old one back on with the marks i made lined up and ran the same as it did with the new one. in park it idles high around 1500rpm and wont come down even after it warms up. if i put it in drive it will even out and not sound so choppy but still sits around 1000rpm. it also gives itself short revs. here's a link to a video of it running, help would be awesome cause I'm lost as to why its running like this.

link to truck running


like to the Actual IP timing not sure if i should advance it more or retard it more


thanks in advance for any and all help!!
 
Welcome to the forum @JonnyTheKidd

install a clear piece of tubing on the return from the IP to the steel line. it's about a 6" piece. the tubing you can get at any hardware store and it does not need to be fuel rated. all your doing is checking to see if you have air in the fuel system. start it up and watch for flowing bubbles.

what it sounds like to me in the video is one of the injectors is not spraying fuel into the prechamber. have you loosened the line nuts on each injector one at a time while it's running to see which injector it is? the short revs sounds like that one injector starts to work momentarily then quits.


what scanner are you using? FYI snap-on scanners are known to give you incorrect timing readings. others may also do this. you really need one of two scanners to verify timing. a GM tech2 or a laptop with some software called GMTDscan.

Here is the summed up procedure for setting TDCO on your truck. get the engine up to full operating temp. loosen all three IP nuts so you can turn the pump. leave the top nut accessible to tighten up while your checking the actual IP timing. set it at close as possible to 3 deg. in my experience 3.5 is too much unless your timing chain is new (no slop) move the IP very very slightly one way or the other, snug up the top nut, start engine and check. each time you go to move the pump, DO NOT run the engine while trying to adjust the pump, very bad things can happen!! Once you get it to 3deg's there are two time settings on the scanner, you use the time set function while your trying to find and move the pump to get 3 degrees. once it's there, then while it's idling, start the timing learn function on the scanner. it will then start hunting for the TDCO. iirc -0.7 is optimal from GM but you can go as far as -1.90 before the check engine light will set a code. But you will have to remedy any current trouble codes prior to doing the TDCO learn function

trying to set the TDCO can be a hair pulling event, the key is to have pleanty of patience

Lets start off by getting the clear return line installed and post a video on it running so we can see if there is any air intrusion. biggest thing is with the intake off, replace all the rubber fuel hoses under there to and from the FFM (fuel filter manager located at the rear of the intake)
 
dbrannon79 said:
Welcome to the forum @JonnyTheKidd

install a clear piece of tubing on the return from the IP to the steel line. it's about a 6" piece. the tubing you can get at any hardware store and it does not need to be fuel rated. all your doing is checking to see if you have air in the fuel system. start it up and watch for flowing bubbles.

what it sounds like to me in the video is one of the injectors is not spraying fuel into the prechamber. have you loosened the line nuts on each injector one at a time while it's running to see which injector it is? the short revs sounds like that one injector starts to work momentarily then quits.


what scanner are you using? FYI snap-on scanners are known to give you incorrect timing readings. others may also do this. you really need one of two scanners to verify timing. a GM tech2 or a laptop with some software called GMTDscan.

Here is the summed up procedure for setting TDCO on your truck. get the engine up to full operating temp. loosen all three IP nuts so you can turn the pump. leave the top nut accessible to tighten up while your checking the actual IP timing. set it at close as possible to 3 deg. in my experience 3.5 is too much unless your timing chain is new (no slop) move the IP very very slightly one way or the other, snug up the top nut, start engine and check. each time you go to move the pump, DO NOT run the engine while trying to adjust the pump, very bad things can happen!! Once you get it to 3deg's there are two time settings on the scanner, you use the time set function while your trying to find and move the pump to get 3 degrees. once it's there, then while it's idling, start the timing learn function on the scanner. it will then start hunting for the TDCO. iirc -0.7 is optimal from GM but you can go as far as -1.90 before the check engine light will set a code. But you will have to remedy any current trouble codes prior to doing the TDCO learn function

trying to set the TDCO can be a hair pulling event, the key is to have pleanty of patience

Lets start off by getting the clear return line installed and post a video on it running so we can see if there is any air intrusion. biggest thing is with the intake off, replace all the rubber fuel hoses under there to and from the FFM (fuel filter manager located at the rear of the intake)
Click to expand...
dbrannon79 said:
Welcome to the forum @JonnyTheKidd

install a clear piece of tubing on the return from the IP to the steel line. it's about a 6" piece. the tubing you can get at any hardware store and it does not need to be fuel rated. all your doing is checking to see if you have air in the fuel system. start it up and watch for flowing bubbles.

what it sounds like to me in the video is one of the injectors is not spraying fuel into the prechamber. have you loosened the line nuts on each injector one at a time while it's running to see which injector it is? the short revs sounds like that one injector starts to work momentarily then quits.


what scanner are you using? FYI snap-on scanners are known to give you incorrect timing readings. others may also do this. you really need one of two scanners to verify timing. a GM tech2 or a laptop with some software called GMTDscan.

Here is the summed up procedure for setting TDCO on your truck. get the engine up to full operating temp. loosen all three IP nuts so you can turn the pump. leave the top nut accessible to tighten up while your checking the actual IP timing. set it at close as possible to 3 deg. in my experience 3.5 is too much unless your timing chain is new (no slop) move the IP very very slightly one way or the other, snug up the top nut, start engine and check. each time you go to move the pump, DO NOT run the engine while trying to adjust the pump, very bad things can happen!! Once you get it to 3deg's there are two time settings on the scanner, you use the time set function while your trying to find and move the pump to get 3 degrees. once it's there, then while it's idling, start the timing learn function on the scanner. it will then start hunting for the TDCO. iirc -0.7 is optimal from GM but you can go as far as -1.90 before the check engine light will set a code. But you will have to remedy any current trouble codes prior to doing the TDCO learn function

trying to set the TDCO can be a hair pulling event, the key is to have pleanty of patience

Lets start off by getting the clear return line installed and post a video on it running so we can see if there is any air intrusion. biggest thing is with the intake off, replace all the rubber fuel hoses under there to and from the FFM (fuel filter manager located at the rear of the intake)
Click to expand...
Awesome, thanks for the detailed reply. I’ll have a update with the clear hose shortly
 
dbrannon79 said:
Welcome to the forum @JonnyTheKidd

install a clear piece of tubing on the return from the IP to the steel line. it's about a 6" piece. the tubing you can get at any hardware store and it does not need to be fuel rated. all your doing is checking to see if you have air in the fuel system. start it up and watch for flowing bubbles.

what it sounds like to me in the video is one of the injectors is not spraying fuel into the prechamber. have you loosened the line nuts on each injector one at a time while it's running to see which injector it is? the short revs sounds like that one injector starts to work momentarily then quits.


what scanner are you using? FYI snap-on scanners are known to give you incorrect timing readings. others may also do this. you really need one of two scanners to verify timing. a GM tech2 or a laptop with some software called GMTDscan.

Here is the summed up procedure for setting TDCO on your truck. get the engine up to full operating temp. loosen all three IP nuts so you can turn the pump. leave the top nut accessible to tighten up while your checking the actual IP timing. set it at close as possible to 3 deg. in my experience 3.5 is too much unless your timing chain is new (no slop) move the IP very very slightly one way or the other, snug up the top nut, start engine and check. each time you go to move the pump, DO NOT run the engine while trying to adjust the pump, very bad things can happen!! Once you get it to 3deg's there are two time settings on the scanner, you use the time set function while your trying to find and move the pump to get 3 degrees. once it's there, then while it's idling, start the timing learn function on the scanner. it will then start hunting for the TDCO. iirc -0.7 is optimal from GM but you can go as far as -1.90 before the check engine light will set a code. But you will have to remedy any current trouble codes prior to doing the TDCO learn function

trying to set the TDCO can be a hair pulling event, the key is to have pleanty of patience

Lets start off by getting the clear return line installed and post a video on it running so we can see if there is any air intrusion. biggest thing is with the intake off, replace all the rubber fuel hoses under there to and from the FFM (fuel filter manager located at the rear of the intake)
Click to expand...
so here is the video of the clear hose. i noticed that it comes up but really dont move
 
Here is what I learned for DS4 mounting orientation on an OBDII platform:
- As others note, make sure there are no fueling issues or leaks.

- Mount the DS4 IP somewhere in an acceptable range of possible orientations. Don't sweat "exactly perfect", just get it somewhere physically in its happy zone. Trying to get exactly perfect is a bit of a fool's game on an OBDII system as the computer will dynamically control timing and it just needs to know that IP's physical orientation is "good enough" for things to work.

- For enabling the TDCO learn, recommend starting with a cold engine. Specifically, colder than 170*F. Setting the TDCO learn is easily done with the ignition key and throttle. Just look around for the steps as there is a sequence of rotating the ignition to "Run" while pressing the throttle to WOT and rotating the key to "Lock" for a set period of time. Please note that rotating the key to "Start" is the LAST part of the process when ready to actually start the engine. Once ECT climbs to 170*F, the TDCO learn will trigger. When this happens, expect a few seconds worth of engine stumble and either the engine will smooth-out, or not.

- If the engine belches tons of smoke after the TDCO learn and is still not happy, get a reading of the IP's position per scanner, turn the engine off, physically rotate the IP a bit (per reading on the scanner), wait for the engine to cool, and repeat triggering the TDCO learn.


As it seems the 6.5 is a new-to-you purchase, might consider some research on which parts to carry in the truck. Related, where is this truck's electronic pump driver (aka: PMD or FSD); on the IP? If on the IP, best practice is to get a remote mount kit. Keeping the driver on the IP will shorten its life.
 
By the way, yanking the IP and re-installing it without telling the computer will probably not change results as the computer remembers its last state. Put another way, need to trigger the TDCO learn routine after each installation / rotation of the IP, otherwise the computer will not change anything despite a physical change on the engine.
 
watching your video it looks as if there is nothing flowing from the return. that is really strange. this is with the new IP installed or the old one? if new, was the old one acting like this as well? are there any codes showing up on the scanner?

other things to verify is fuel pressure from the LP. if running a stock GM LP, you should be seeing 8-9psi at idle. 5psi is ok-ish and should still run perfect. it's when there is no pressure you start to see issues.


if all above checks out, it's probably stuck in TDCO learn mode and will need to run up to operating temp before it will complete the TDCO learn process.

@Will L. , @ak diesel driver what are yall's thoughts here?
 
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