Hey i was wondering if there was anyone out there that could give me information as to how to go about getting my truck running properly again after installing a new injector pump? I get the truck started but it runs really bad and sounds as if there is a misfire. It also starts easier if i remove one of the injectors. I have a snap-on MT2500 but cant seem to find any info on it other than clearing of the DTC's and the reading of all other figures. I have the workshop manual on the truck but all that it tells you is how to line up the timing marks when installing the new pump???http://www.dieselplace.com/forum/smileys/Confused.gif Edited by: TfourCT

Hi T4CT welcome to the forum tweak down your font a notch, add some info to your sig line it helps us figure out how to best advise you and you don't have to keep updating what your truck is, I don't have procedure for OBD I which is what yours is QM, TDG, or GMCTD will be along shortly they know OBDIEdited by: Turbine Doc

Unplug the Optic Sensor - top, rear on inj pump, plastic plug - start the truck and it will run in "limp" or "back-up" mode.


Let it run for ~15mins to clear the pump and lines.


Kill it, re-connect the plug, re-start and see what info the 2500 gives you - Desired Timing, Actual Timing, and TDC Offset

What series pump did you replace? 5288? just curious. Waiting to hear what the des/timing is running and what codes it was giving if any.

Hey there Quantum Mechanic, i have just gotten a new crankshaft position sensor and put that in and have now tried starting the van again. Unfortunately the van doesnt want to start and when i see what the injection timing is it says 14 and the desired is also 14 but the TDC offset is -0.3. Will any of this change once i get the vehicle started? I will keep you informed as to my progress.

Timing comes down a little after it starts, make sure you didn't accidently unconnect the coolant tempature sensor on the water crossover. It will take timing to 14 act/14 des and make it impossible to start. Try pushing the pump to the drivers side 1mm, a slight advance.


What exactly is happenning?


Do you see a cloud of smoke when you're cranking? Does it almost start? Did you pressurize the fuel bowl by jumping the fuel pump relay? i had a hard start after i put a fresh pump. Took a lot of cranking to get it to catch and then it ran fine. Try starting it while jumping/boosting the batteries.

Hey Quantum Mechanic, tell me did you have to do a timing learn proceedure when you replaced your pump? I purchased the 5288 pump and installed it. I got it running at first but it was terrible and lacked power. I then tried setting the pump a bit differently and it has just gotten worse. It has gotten to a stage now where i cant even get the thing started anymore. Since i have put in the new Crankshaft Position Sensor there is a heavier smell of diesel while i crank it. It sound almost as if it is going to take but then doesnt. At first when i had it running before now with the new pump in i had a rather loud knocking noise coming from the engine and it was smoking rather badly from the breather pipe. I was told by some one that it was the motor that had broken a piston and then i was told by someone else that it is more than likely just over fueling. I did manage to get it started a whole lot easier if i removed one of the injectors. Tell me if you did have to reset the pump after changing it do you know where i can purchase a cartridge for my Tech I for the 6.5 engines and ECM's?

Tfourct,


I did no timing learn proceedures, My scanner doesn't have the capability. Your's sounds like too much fuel, check the Coolant temp. sensor. it's exposed and I've broken it more than once myself. when it breaks off it dumps fuel into the motor.


What was the series number on your old pump, if it was 5068 you have to upgrade the prom to a higher series, costs $40 from gmpartsdirect.


get it up and running and tell me your timing des/adv.


Are you seeing the crankpulse counter at 0.0 or counting?Edited by: quantum mechanic

Quantum Mechanic,


I have checked the coolant temp sensor and it appears fine.


The series number of the pump that i replaced was 5067. Will i have to upgrade the prom for it to run correctly?

The way I understand it, you shouldn't have to replace the prom because of the pump going from 5067 to 5288. Only the 5068. but if the ECM you replaced the first with was a "s" engine instead of "f" engine it will cause problems. I still suggest switching proms from ecm's.


It would be best to get it running again, to be able to set it right, have you been able to start it again?

Still havent been able to get it started yet, i am however persevering and hope to atleast get it running again. Will try once again tomorrow and let you know. Thanx for all the help im sure its as annoying for you with all these questions as it is for myself having to ask themhttp://www.dieselplace.com/forum/smileys/Confused.gif

Make sure you have good connections on your batteries. The stock connectors are weak and they tend to corrode. also check your glowpugs.