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Truck Runs Real Rough, Please Help

Yes, it does seem like a heat soak issue. Like earlier, after it sat for acouple of days, it ran great for about 20 minutes. Then I shut it off and let it set for 1/2 hour or so and it started running rough as soon as I started it up. An injection pump would act like that?
 
What are the latest DTCs?

An opening in the line at the IP itself could have sucked in air as well. Since there is a pressure drop across the filter, you may never see a momentary vacuum at the IP. When demand is greater than the pressure it has this other source to pull from except its not fuel. You might check WOT LP pressures again now see if they are lower.

But obviously that clamp hasnt resolved the issue. You might try idling for 30 minutes and then you drive it? Make sure the clamps on the fuel manager are good, my have to unbolt it. Might want to check the condition of the IP feed line in the engine valley. And put a clear line also on the IP return.

Heatsoak sounds like an IP or OS issue. You had so many codes that didnt seem to go together if one thing was wrong, unless they werent current. If the fuel solenoid was sticky you wouldnt get a CPS or OS code and if timing wasn't reading right would not get the 35 and 54. When you get them all seems to point to some air.
 
Guys, Before I take it for a test drive I pulled the codes. These are the codes that are showing up now.

Code 18 Pump Cam Reference Pulse Error
Code 35 Injection Pulse Width Error (Response Time Short)
Code 36 Injection Pulse Width Error (Response Time Long) THIS A NEW ONE
Code 54 PCM Fuel Circuit Error

I will go out and take it for a test drive in a little bit.
 
Well, Here's what I did now. I took it for a test drive and thought I would stop every once in a while, even though it was running okay, and check for codes. I got no codes for a while. Then it started running bad and I stopped and checked for codes. I got
Code 18 (Pump Cam Reference Pulse Error).

I then drove it around somemore but didn't really push it that hard. It did run rough though other than it did idle okay at the stop sighns. But any throttle it would run rough. A friend called and wanted to meet me at the pizza palace and I parked on main street to eat pizza. 45 minutes later I got in and it would fire but not start. I opened up the hood and poured a bottle of water on the injectiion pump. I got back in and it started up and idled fine but still rough when giving it throttle. I drove towards home. I stoped once on the way home and checked codes and 18 was the only one still there. I believe if I would have pushed it more I could have got it to throw more codes. But I figured it might be better that it threw just the one code. The 18 is what is making it run like crap. Any ideas about what this is all about. Hope it helps. Just trying to do the testing alittle differently so something might might be more apparent what might be wrong. Thanks Guys.
 
That points to the actual OS failing most likely, which typically would be a whole IP replacement. Even the manual states this could be due to air though. But water on it wouldnt help, unless the amount of cranking passed the air.

I would drive with the OS unplugged, it will set DTC17 and 18 and you will be in backup fuel mode, which sets a contstant pulse width and uses only the crank sensor for injection timing reference. It will feel low power, but should drive ok. If you still have issues then it is likely more.

Do you use any fuel additives, anything in the fuel?
 
Buddy, I have been reading about code 18 and yes it looks like the optic sensor. I can't just replace that? It looks like it is the black cap item on the top of the pump? Or is it more internal?

I have been putting in 16 ounces of diesel clean in each 42 gallon tank. Also I have been putting in 16 ounces of 2 cycle oil in each tank.

Do you think I have bad fuel? I wouldn't think so being it runs okay for a little bit until it warms up?

I am checking the vin. and seeing when the injection pump was or if it was ever replaced. I have 220,000 miles on the engine.

I will also move the clear hose to the return side of the pump Tomorrow. I have read that if there is bubbles on that side that the Injection pump is bad?
 
You can disconnect the OS and if you can get a multimeter across pins A and D of the cable there should be 5V there with the ign on, that comes from the PCM. And when I check ohms with ign off there is 39kohms.

You can just replace the OS if you can find one, but then its not exactly calibrated correctly, not that it matters a whole lot. The OS does go internal and you can get the idea here, not terribly difficult
http://www.mamut.net/royh/newsdet9.htm

What may happen is the OS could be shorting out when it gets hot and causing your other circuit failures. Backup fuel mode (limp mode) with the OS unplugged should work better than with it plugged in coding the DTC, if that is the case.

I'd still throw the clear line on the return to check that though.
 
Optic sensor replacement is not for amatuers from what I have seen. I would do the IP. The rest of the IP is probably not far behind not to mention IIRC the OS is pricey, around 300$ I thought I read.
 
Buddy, I searched around for location A and D on the connector. I can't seem to find what pins are what. Can you send me in the right dirction so I know what pins to check for power on the OS? Thanks.

I should probably take out that OS filter harness and try running it with that removed?

Acesneights, I probably will just rebuild the whole pump rather than just replacing the os. Thanks.
 
It gets ditched so often its forgotten

The connector is labeled.

If youre staring at the sockets with the locking tab on top what you have is
D E F
C B A
 
Hey Guys, Just got in from testing the burb again. I did put the clear hose on the return. I drove it around until it started acting up again. I then checked the hose for bubbles at idle and in drive as I was pushing on the throttle making the engine run rough. There was no bubbles in the line. I was still coming up with 18 for the code.

I then took the top of the intake off to get at that filter harness. I took it out and plugged it in with out the filter of course. Nothing changed. Still ran rough. Took it out and pushed it a bit and got it to go into "service engine soon" mode. Pulled codes and got 18, 35, 54.

I then disconnected the OS and started it up. It cranked for a while before it would start? Service engine light was on and I took it for a ride. It ran good. Mabey alittle less power but at least it wasn't missing and trying to backfire.

I will go out in a little while and test the OS connector for voltage and ohms. My dad gave me a good digital tester a while back and I am not sure I know how to test for Kohms though.

I have spoken with a few friends and a few guys that have worked on the 6.5's and they all say the pump. But they probably more like the dealers that would just throw parts at it and ask questions later. I am sorta leaning toward the os but that is just me. Hopefully I can read this meter to make sure something isn't wrong up stream. Thanks Guys.
 
Its normal for hard starting with either OS or CPS unplugged. But if it runs better without the problems with it unplugged then the OS must be the issue. And if it still runs bad after the code it must be an OS hardware problem that still affects the PCM even after it codes and ignores the input for timing reference.

Most people just replace whole IP, which is more work than just the OS, but OS isnt cheap or readily available, unless you swap out of a pump that had a mechanical problem. A couple guys just disected IPs might have one.
 
Buddy, it runs good without the o/s plugged in. Other than you have to spin the motor over acouple of times to get it to start. The codes are there though when it isn't plugged in and service engine light is on. It did always run alot better once the service engine light came on. I have a friend coming over to check the plug in a few minutes so I will let you know what we find for voltage and 1000 ohms. Thanks.
 
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