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1995 Chevrolet C3500-HD

DieselCash

DieselCash

Trust but, verify
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Got me a new to me truck. It is running ruff(sometimes) and throwing some codes.
Here are the codes I got;
15-low temp
18-pump cam reference pulse error
35-injector pulse width error
54-pcm fuel circuit error
78-turbo waste gate solenoid fault

It puts way too much black smoke out the tail pipe when I accelerate. I really think the turbo control is not working properly.
Sometimes it runs great, then the motor hiccups/jerks then the check engine light comes on. Then it starts to run ruff.

The PMD is mounted on the firewall on a heat sink. I do have a spare but, not attempted to use it.
I plan on moving it to the bumper, just not sure if current cable is long enough.
The engine just had a fresh rebuild, with a known running injector pump.

I have not checked grounds, yet! It will be first on my list. If that is the problem.

As many of you know, I am not new to the 6.5 world. Just new to owning one with a PMD!!

Any ideas??
 
18, 35, and 54 together to me would point towards either an injection pump, or optic sensor issue. 35 I know from personnal experience can be pmd, but seeing the other 2 with it makes me lean towards a pump issue. Make sure it has good fuel, do the ops relay mod, and install a new ac delco ops. The 78 is probably just the boost solenoid, and the most likely cause for your black smoke. And 15 is probably a t-stat(get one from leroy as he has the good ones).

And is this a real 3500hd, or just a 3500 dually?
 
This is the 3500-HD.

Could the injection pump/optic sensor be from bad wire connections? Do you think cleaning with electrical connector cleaner would help?

I have a spare PMD, maybe I should swap them out.

It runs good when I first start it. Then out of no where the motor does this weird shake and the check engine light comes on.
 
I'd test both the CPS and the OS. The procedure is to unplug one of them and then start it. It will take extra long to start and will be in limp mode when it does but if it runs smoothly without any issues then which ever one it is running on is good. Re plug and unplug the other to test it.
 
OPS needs good clean air free fuel. Foam screws it's vision up.

*AHEM* start by checking for air with clear return line. Lift pump working, plugged sock, fuel filter, gasoline in fuel, water, bugs...

Then do grounds.
 
Tried finding something in the tech library but the links appear to be dead. Maybe a Mod could get them fixed. Hint hint,
The CPS is down by the front crank seal, follow the wire up to behind the fan where the plug is at. The OS is the square black box on the top of the IP, plug is on it
 
Also, hook a vacuum gauge to the tube/hose at the solenoid, the hose from the vac pump, be sure there is vacuum. if around 20/25" of vacuum then vacuum will need to be tested after the solenoid. Also, be sure that the turbo wastegate control arm is moving free, without any binding.
 
I have a clear line going into the pump. It does not show any bubbles, just fuel.

I swapped out to my spare PMD last night. On the short drive to work, it ran better than it ever has. We will see!

I will play with the turbo next. I will put a turbo master on it before I spend the money on the new pump.

Grounds!!! Will be soon.
 
Well, I spoke too soon. Check engine light is back.
I followed what "AK" said. I unplugged the one that goes down the front of the motor.
The truck would not start. Not even try!
So I am guessing my CPS is bad. I will start with that.
Is this another one of those components that should only be an ACDelco part?
 
Well, I hope it is not the Optic Sensor that part is almost $300! Stanadyne 33883
The CPS is $82.99 @ O'Reilly's for a ACDelco 213-337. Amazon is half the price $45.98.
O'Reilly's is always high on there ACDelco parts.
 
CPS, Crank Position Sensor... is :facepalm: on the front of the engine and what you unplugged. Looks like it's fine and your real issue is related to the OPS on the Injection Pump. Look at your harness for a harness filter! It goes from the OPS to the main harness. it's about 4" long with connectors on each end. Just take it completely out and try the CPS disconnected test again. Note It may take a bit to start, but, never crank more than 30 seconds.
 
WarWagon said:
CPS, Crank Position Sensor... is :facepalm: on the front of the engine and what you unplugged. Looks like it's fine and your real issue is related to the OPS on the Injection Pump. Look at your harness for a harness filter! It goes from the OPS to the main harness. it's about 4" long with connectors on each end. Just take it completely out and try the CPS disconnected test again. Note It may take a bit to start, but, never crank more than 30 seconds.
Click to expand...

I do not see the 4" extension harness. That little plug is buried deep under the intake horn.

Would the truck run if both were bad?
 
I took off the upper intake. I unplugged the OPS and put it back on.
The truck fired right up, ran ruff. But it fired up.
So, I am guessing the OPS is bad. The more expensive part! Just my luck.
 
It just can't be easy can it! I will play with wiring before I change out any parts.
I am all about not spending my wives money!!!
Every plug I pulled apart, I sprayed both sides with electrical connector cleaner.
Maybe I will get lucky and it will be that easy.
Thanks to everyone that has replied and helped me out, I really appreciate it!
 
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