Hi, I got a 2003 Cummins that have a start issue.

It started with a few times that it did not want to start and suddenly it started.
I figured out that during start it use camshaft sensor but when it runs it use crankchaft sensor, so I tried some starting gas when it didnt start and it fired up and runs as normal.
Now I have to use starting gas all the time.
Without starting gas I can crank it forever but with a little starting gas it fires up and runs directly.
From time to time I get an error code, dont remember the P number but it points to the crankshaft sensor that I have replaced with a new.

Anyone have any idea? (and sorry if I misspelled anything, I am living in Sweden )

 

Is the Check Engine Light lit up when it is running?

Are you letting the warm-up cycle finish before trying to crank?

When was the last time you changed the fuel filter? (if more than 10k miles DO IT NOW)

 

I hear diesels get addicted to that stuff

 

No, I have not changed the fuel filter for a very long time and have now ordered one today.
I think the problem is fuel related and if I turn it of it will start again but the time it can be turned of and started again is getting shorter and shorter, now its like 1 minute
But I dont see the logic with the filter, if the filter was stopping the fuel it wouldnt run as normal when started with starting gas, would it?

Yes I run the warm up cycle when I try to start it without starting gas, but not with starting gas since the heater can ignite the gas.
I got the same problem even if the engine is hot.

If I crank it for a long time (like more then 30 seconds) without strating gas the check engine light lits and I get the error code P0336 (pointing to the cranshaft sensor), it will then go away if I use the starting gas for the next few starts.
When I read live data when cranking I can see the RPM so the crankshaft position sensor should be OK, or?

 

If you mean the instant start spray... that is TERRIBLE for your motor.... you should not be doing that.... as it is causing the engine to run lean... and if you keep doing it, or you get enough built up you might end up with a runaway diesel situation where it stops running on fuel and starts running on the oil in the crankcase... then you'll end up with a catastrophic failure...

Replace the fuel filter, what might be happening is that your filter has debris in it that are settling to the bottom and then getting sucked up when you try to start the truck thus blocking the fuel supply and causing the truck to stall.

The crankcase sensor error is fairly serious and I would definitely replace the sensor to be safe regardless....

But it definitely sounds like a fuel problem... to confirm this you could hook up a fuel pressure test gauge to the fuel rails (one at a time unless it's a high end test kit) and you'll see if you have fuel pressure...

Another question I have for you... did you run the truck until it was completely out of fuel?

If so, you might just need to re-prime the fuel system:
Let us know how you make out once the fuel filter is replaced, and be sure to follow the steps in your manual on how to change it.

 

Hmm, yes that is what I am using
And the crancase sensor is allready replaced without any difference
Filter will be replaced during weekend.
The priming procedure is not working on my 2003 since it has a different high pressure pump.
The procedure for my 2003 seems to just letting the liftpump run, so then it should be primed everytime I run the engine.

 

Then just change that Filter ASAP, if the problem persists then we'll need to look at the fuel pressure getting to the rail.

 

Filter changed.
Now it starts instantly

You are my hero , Next time you are in Sweden I will buy you a beer

And.... I will always from now change the fuelfilter at every service....

 

I may be there in August...all depends on where we decide to go for my HoneyMoon....

Just remember to change that filter as instructed by the Manual... Rule of thumb is I believe 10,000 miles (16,000 kilometers)...

B/c the one that you had in there was completely clogged I am betting you'll need to change it sooner... Prolly around 5000 miles (8,000 Km).

I always tell people to keep an extra fuel filter on-hand just in-case.

 

Well, I know that this filter was not changed for at least 30.000 Km
This is my first diesel so I have learned one thing

I think southern Sweden have kind of the same weather as you have, in August its around 20C (68F) and 18C (64F) in the oacean, around 10C(50F) the north.
If you want cold and snow you should visit Northen Sweden in February-Mars.
Here is what me and my son is doing during winter (end of Mars)
If you decide to visit Sweden I can recommend you some places to visit if you want (I know the west coast around Gothenburg and the Northen part around Östersund), the Northen part of Sweden is a very low crime area were almost everyone can be trusted, we even leave our car keys in the ignision.