Crank, No start 2007 5.9 (fuel related)

[Oleinik07]

2007 5.9 Previously have had an occasional problem where I would go to start and she’d start up, run, then die after a few seconds, sometimes would happen a couple times before starting and running completely normal. Well this time it’s not starting at all. Cranks great just won’t run. My lift pump is fine, brand new filter, I capped off each injector line and cranked thinking that there was too much return fuel, unplugged FCA and tried it, capped the pressure relief valve, I know my CP3 is working and putting out pressure but haven’t got to test actual psi. No check engine lights except for P0541 (low voltage to intake air heater relay. It’s been on for about a year lol) Compression is great - just rebuilt the engine about 10k miles ago. Went ahead and shot some ether in there and it would turn over but not run. The weird part is that once it was running I never had any loss of power or economy. Still had been averaging about 23 mpg combined. Possible it is an ECM issue but surely there would be other problems or codes? Any ideas Gents?

 

[sag2]

If it won't run on starting fluid it is not a fuel problem. Highly unlikely it is mechanical all of a sudden. Are you sure you gave it enough starting fluid?

 

[Oleinik07]

If it won't run on starting fluid it is not a fuel problem. Highly unlikely it is mechanical all of a sudden. Are you sure you gave it enough starting fluid?

it completely turned over off the starting fluid but did not keep running.

 

[Ozymandias]

Are you be able to monitor crank and cam sensor during start up/cranking?

It seems from the distance that your ECM denies to fire the Injectors at all.

No codes doesn't mean everything is fine on this side.

 

[Ozymandias]

Double

 

[Oleinik07]

Are you be able to monitor crank and cam sensor during start up/cranking?

It seems from the distance that your ECM denies to fire the Injectors at all.

No codes doesn't mean everything is fine on this side.

I’ll probably have to take it into a shop to monitor those. I don’t have the equipment unfortunately. Thanks for the pointers.

 

[cerberusiam]

it completely turned over off the starting fluid but did not keep running.

This makes no sense, please clarify what that means. Sag2 is asking if the engine FIRED on ether not if it is turning over, the starter will make it turn over but not fire.

If it is firing on ether then you have a fuel or ECM issue. COV stuck in bypass mode, CP-3 is bad, possibly ruptured a cross over tube, or ECM is bad. If you can get the engine to fire on ether and keep it firing for one series of the firing order and it still won't run the injectors are not being fired, lack of fuel pressure and\or the injector drivers are not being activated.

 

[Oleinik07]

If you have a bad injector that is causing the no start problem you can get your engine to start and run on ether. When I sprayed some and cranked, the engine turned over but did not keep running after the ether was used up. So yes. It fired on ether.

my thoughts also. But bad ECM would probably manifest itself other ways also? Also it seems unlikely for the ECM to slowly go out. It seems mechanical or like you said a leak in a tube that got bigger maybe? Maybe it is the CP3 but also seems odd that I never had loss of power or economy when it would run after having the initial starting problem.

 

[cerberusiam]

I don't know how you are driving, speed, climate, etc., but if you are getting a true hand calculated 23 mpg at any type of normal road speeds something is broke. I can see that in a 2x4 at 50-60 mph but it ain't happening in a 4x4 at 70 mph. If the CP-3 is failing that could and would boost mpg.

Have you actually put a gauge on the CP-3 inlet to make sure you are getting good fuel pressure at the CP-3? You said the LP is good but how did you validate that?

Have put a scanner on the ECM to see if there any stored codes? Injector drivers, or harness, can fail and that is al you will see is no fire. Sometimes you can get a code that would indicate a problem but you have to have a scanner that will read the Ram specific codes.

Loss of power is to relative to gauge. What you see as no loss of power I could see as being a major problem. You have to monitor engine operation parameters ot find some of these problems, that takes a scanner or gauges, and might be the only way to identify the problem.

 

[Oleinik07]

Yeah I have a 2wd and never really get crazy with it. But that’s what the truck is reading like you said probably not that accurate. CP-3 is pumping fuel like I said but I haven’t got to test actual pressure. That’s my planned next move. Same for LP, I pulled the filter out and cycled the key and the pump came on and filled up the filter bowl completely.

I have put my smarty on it and it didn’t show any other codes than the one I mentioned. I’m not sure if a better scanner would read something else.

probably am just going to need some more sophisticated equipment like you said. I wanted to avoid taking it to a shop but that’s probably what it’s going to take. thanks again

 

[Ozymandias]

If you are willing to invest you could buy Autoenginuity for your Laptop to do your own diagnosis.
But that also need your knowledge how that all works together.
Diagnostic is way more then just reading a code, we wanna see graphs and more from every sensor involved in fueling, see the whole picture. A code is most of the time no more then a slight hint.

Sometimes a good Dieselshop is the better way of.

 

[cerberusiam]

If you have updated the Smarty it will usually show you all the codes that are there. I would look at the actual rail pressur eto see if it is building and go from there. If it is building to at least 3000 psi on a scanner that can read it then it is likely an ECM issue. If it never gets to that point cranking with starter it won't ever fire and you need to verify LP pressure at the CP-3 and the mechanicals from the CP-3 to the injectors. There are a lot of mechanical failure points that will never show up as codes, they cna be deduced by looking test parameters if you know what to look for.

 

[Oleinik07]

Well I finally got it to throw a code. It threw a code for the chip in the key. I forget what the exact code was but anyway, I grabbed my spare key and the stupid thing cranked right up and I drove it home. Thanks for all the help I appreciate it.

symptoms were it would crank up fine and run for about 3 seconds or so then die. It would do that for maybe 3 or 4 cranks until it would just stop turning over and just crank. When it would turn over it ran perfect and you could even rev with no problem within that time period. I don’t know why it took so long to throw a code for it. But yeah I was using my smarty for a scanner they do pretty good

 

[sag2]

The other clue that would have been helpful was the little red security light was on when it would start and die. Sorry we didn't catch that.

The other helpful advice is the difference between no crank (not turning over), and crank (turning over). An engine that does not crank with the starter does not turn over. An engine that cranks but does not start turns over. I think your description had us confused.