Archived 06 wont start?

[Drue]

I need help to figure out why my '06 wont start. It will crank over at appropriate speed, but no start. It seems to try, but it seems to only be firing on a couple of cylinders... . ? I did plug in my smarty jr and it says I have no trouble codes? I did plug in another scan tool to diagnostic port and it shows cranking rpm ~300, fuel psi >35K. (I did already change fuel filter just in case I was over looking the obvious,)



I would truely value any thoughts/suggestions #@$%! from someone more experienced.

 

[BigPapa]

Injectors. How many miles on your truck? Somewhere @ 130K-150K?

 

[Drue]

current mileage = 73,504.

wouldn't a faulty injector(s) cause a trouble code and low rail psi?



The truck is still stock, I am satisfied with the power, and wanting durability, driveability etc... .

 

[BigPapa]

Anything's possible but from your mileage I wouldn't think it's injectors.



Carry on.

 

[Drue]

Update: I have checked everything I know to check. I tried long duration cranking due to it sounding like it 'wanted to crank. ' After many 30 second start attemeps, it started to run. But only at ~400rpm. Did not sound right at all, very rough, no throttle response at all with some visable smoke out of exhaust. It was as if the injectors had run out of fuel and had air in the lines. I shut it off to check again for any visable sign ot trouble, found none. No fuel leaks can be detected, as all of the fuel lines and engine is dry and dusty. After another long cranking cycle, same thing again. Still no codes. I let it run longer and it seem to build a little more rpm and smooth out. Then it started to respond to throttle position and seemd to clear itself and run.



What do I do next? There is something not obvious, but definitely wrong... .

 

[jhenderson]

Are you sure the lift pump is working? Pull the top and bump the starter. If you don't have a strong , clear fuel stream, that is where I would look. Is it possible you didn't prime the system quite enough after the filter change?

 

[Drue]

This problem started before I changed fuel filter. It had been ~15,000 miles on the old filter, so I thought it might just be due to be changed. This filter change did not change any condition of truck starting.



I can hear the fuel pump running when I take the fuel cap off and bump the starter, sounds normal. I did open the water drain on the fuel filter housing and bumped starter to engage the fuel pump, seems to be good flow. I have no other easy way to test flow rate. Any suggestions?



When you wrote " pull the top and bump the starter", what are you referring to? The top of what?

 

[jhenderson]

Sounds like you have enough fuel. Possibly crank sensor? Anybody else?

 

[Missouri Mule]

Fuel Control Actuator? The FCA can cause hard and no starts. Sometimes will set a code but most times won't. Located on back side of CP3.



Read in TDR can of ashless out board oil in fuel tank will verify FCA but Joe Donnelly (TDR Writer) doesn't recommend this!

 

[KRStone]

I was thinking water in the fuel

 

[Drue]

Yes I was wondering about that (water in fuel) untill I looked at fuel that came out when I was checking flow. It looks clear with slight green tint and no water evident after it sits for a few hours. I did get some water in it after it rained, but I dont think that was the problem.



I don't know, but I thought the WIF sensor would have signaled before a no start situation would happen. But I seem to have more questions than answers.



I am questioning the FCA. Would this be a problem if durring the no start, the rail psi is over 35,000 psi?



Please keep the suggestions coming. I need to be able to fix this myself. I can't afford to take to a dealer now that I am not working for a pay check for now.....

 

[Missouri Mule]

The FCA determines the amount of fuel that goes into the rail it mite determine pressure also but I don't know about that.



35,000 psi in rail at start up is way to much pressure your relief valve should be popping open at that pressure. It should be in the 3,500 to 5,000 at starting.



Water in fuel,fuel would have bubbles (water) in it. Not good for injectors.

 

[Drue]

The FCA determines the amount of fuel that goes into the rail it mite determine pressure also but I don't know about that.



35,000 psi in rail at start up is way to much pressure your relief valve should be popping open at that pressure. It should be in the 3,500 to 5,000 at starting.



Water in fuel,fuel would have bubbles (water) in it. Not good for injectors.

I should probably go check and verify with my reading glasses that I have the right number of zeros in the 35,000 psi number. (Another one of those signs of growing older / blinder etc... ) I will try to verify and get back to you. Thanks!!!

 

[BigPapa]

I'm leaning more toward a senor such as a crank sensor. The only thing is no DTC's.

 

[HHhuntitall]

I worked on one last month that did the same thing. It just died going down the road. My first thoughts were bad fuel pump, stuck injector, or bad sensor. Ended up being the CP3 took a vacation, at 89k miles!! . FCA sensor could be the culprit, as well as the Cascade overflow valve, crank sensor, cam sensor, stuck injector, rail pressure limiting valve(pop-off valve). If the Smarty shows 3500 psi start pressure in the rail, I'd look at the Cam, crank, or APPS sensors. First, though, I'd verify the fuel lift pump is working. jenderson was referring to taking the top off of the fuel canister where your filter is located.

 

[Drue]

Update: Truck is running. (I am still worried because I do not know why). Cranks and sounds completely normal.



My scanner tool shows (SNAPSHOT MODE) the following info:

FUEL PRESS KPA 46050

ENGINE RPM 751

BARO PRS KPA 101

CALC LOAD % 1. 1

MAP KPA 101

OUT TEMP F 93

COOLANT TEMP F 129

IAT F 95

VPRW V 14. 5



When the engine is running, these numbers fluctuate some, with fuel pressure going as high as 48260 while engine is idling. When I rev the engine, I have seen numbers upto and beyond 65,000, but it is not on one number long enough to read all 5 digits.



I am planning on using the truck to make a couple of 80 mile hauls today pulling 8-10,000 lbs. So I will give a real road test and report back. I think I will take my scanner and see if it can detect anything while traveling under load.

 

[Missouri Mule]

Sounds like your rail pressure sensor is acting up. If it is correct you will have injetor(s) problems soon.

 

[HHhuntitall]

Notice, the pressures are in KPA... 65,000kPa converts to like 9427psi... . 46050kPa is 6678psi..... It doesn't sound far out of spec..... It appears to me to be electical, as in a sensor or wire, working intermittently. Lack of codes is strange... . Cascade valve, perhaps? I think a component test would help eliminate some questions and possibilities.....

 

[Missouri Mule]

PSI! Those numbers are more like it.

 

[sg5054]

You may want to consider a air leak on the suction side. Refer back to you comments in post#5. Hard starting, rough idle, low idle speed but eventually smoothing out and gaining rpm's the longer it runs. All are indicative of air in the fuel supply. Check your lines for cracks or chafing, fittings for cracked or missing o-rings or gaskets, filters for missing or doubled gaskets. Try disconnecting the supply at the lift pump and run it out of a bucket. Entirely possible to have a suction leak and not have a external fuel leak.
We used to disconnect both supply and return lines on HD diesels (Detroit, Cat, Cummins, Mack etc) in the hunt for a leak and run from a bucket watching for air bubbles and foam. Run it at idle and at high idle to compare. You should be getting just clear fuel returning to the bucket with the return line below the surface.
Air in the fuel would not throw a code.