6.5 running like crap after new IP install

[JonnyTheKidd]

@dbrannon79 this is the new pump. the truck was running perfectly fine before i took the old pump out. i replaced it cause it was filling the valley with fuel. so the new pump was acting this way, so i put the old one back in, lined it up with the punch marks i made and it did the same thing as the new one. but yes the fuel is just sitting in the return line and not moving. ill run out and check the LP pressure quick and check for codes

 

[dbrannon79]

you can also pull the return hose off the steel line and run it into a soda bottle to catch it. to see if there is actual flow. just cap off the return steel line before you start it up.

ok so prior to removing the old IP it was running fine, installing the new one and it started this as well as putting back the old one it now does the same. that says more than likely the ECU is stuck in TDCO learn mode.

as long as all the codes are clear and LP pressure checks out, and once you get the actual IP timing set to 3-3.5. try keeping it running till it gets up to at least 170-180 on the engine temp. see if it tries to go through the learn process.

if the IP is adjusted too far one way or the other, it can shut off on you while it hunts for the TDCO. I usually have really decent luck when I get the actual IP timing right at 3 degrees.

 

[dbrannon79]

you might have two possible codes pop up that you won't have to worry about. one for engine temp and one for the IP out of range. I can't recall the code numbers right now, but if that is all the shows up on the scanner, its saying the engine needs to get up to temp before setting the TDCO and the other code is because it can't complete the learn process.

But if it lists codes, post them with the code numbers and we can help work through them.

 

[dbrannon79]

BTW.... I see you have the upper intake off. Good. keep you a plank of wood or something (not a rag) that is rigid near by so if it tries to run away and rev to the moon, you can use the flat plant to snuff and choke it and save your engine. there is always that risk.

 

[JonnyTheKidd]

BTW.... I see you have the upper intake off. Good. keep you a plank of wood or something (not a rag) that is rigid near by so if it tries to run away and rev to the moon, you can use the flat plant to snuff and choke it and save your engine. there is always that risk.

so the fuel pressure is sitting around 5 psi at the IP

the code i have is P1218-Injection pump calibration circuit

i also have a perfectly cut block of wood on standby! lol

the actual ip timing is tricky cause it fluctuates so much.

the return line seems to have no flow for some reason but can vacuum fuel out in a solid flow.

 

[JonnyTheKidd]

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.

i have the pmd located on a heatsink near the fuse box

 

[dbrannon79]

P1218 indicates a possible missing or failed PMD resistor. check to make sure the resistor is still inside the PMD connector. if it is, pull it out and use a ohm meter and measure it. also what # is printed on it? usually the put a #5 in from factory.

 

[JonnyTheKidd]

P1218 indicates a possible missing or failed PMD resistor. check to make sure the resistor is still inside the PMD connector. if it is, pull it out and use a ohm meter and measure it. also what # is printed on it? usually the put a #5 in from factory.

Is that what this thing is it has a number 6 on it

 

[JonnyTheKidd]

Is that what this thing is it has a number 6 on it

Continuity on all wires I had a guy tell me to pull it out and not use it but I will put it back on

 

[jrsavoie]

i have the pmd located on a heatsink near the fuse box

Best to move it to the bumper.

 

[jrsavoie]

Is that what this thing is it has a number 6 on it

That is the optic sensor filter. It's garbage. Throw it away and plug directly into the injection pump.
Your guy told you right

 

[dbrannon79]

Is that what this thing is it has a number 6 on it

Throw that thing in the trash! Lol. That is a noise filter that is notorious for causing issues

 

[dbrannon79]

The resistor I’m talking about is inside the connector on the PMD or sometimes called a FSD. They are mounted on the side of the IP from factory but most of us relocate it to the bumper and run an extension from the harness to it. I’ll get you a pic of it

 

[dbrannon79]

 

[dbrannon79]

If your resistor is good it may also be a loose connection or wiring issue on the harness or if using an extension cable.

 

[dbrannon79]

Here is the info on the P1218 trouble code

GM/Detroit 6.5L ENGINE CONTROLS – DTC P1218 Injection Pump Calibration Circuit - Diesel Engines Troubleshooting

Circuit Description The PCM uses a calibrated resistor mounted internally in the injection pump to determine fuel rates. The resistor value is stored in the PCM memory. If the PCM memory has been disturbed or the PCM has been replaced, the PCM will relearn the resistor value on the next ignition...

www.dieselmechanic.info

 

[jrsavoie]

On the 1994 I had a pin in the Injection pump harness suddenly lose connection.

Everything tested fine for continuity. But one pin wasn't making.

I tried several extension harnesses and PMDs. I made up a T harness to check for juice coming back from.the PMD.
When I plugged that harness in, the truck started.
I don't remember what I did after that to figure out the bad pin.

 

[JonnyTheKidd]

If your resistor is good it may also be a loose connection or wiring issue on the harness or if using an extension cable.

ill check the resistor in the morning i have the pmd mounted on a heatsink next to the fuse box the pmd came with the new pump

 

[JonnyTheKidd]

On the 1994 I had a pin in the Injection pump harness suddenly lose connection.

Everything tested fine for continuity. But one pin wasn't making.

I tried several extension harnesses and PMDs. I made up a T harness to check for juice coming back from.the PMD.
When I plugged that harness in, the truck started.
I don't remember what I did after that to figure out the bad pin.

the first pump i bought was the wrong one, or something to do with the connectors(gray vs black) and every time i plugged it in it would push one of the pins to far down in the connector that it wouldn't make a connection and in return i got no fuel coming out of the high side of the IP

 

[JonnyTheKidd]

Best to move it to the bumper.

will do