Truck won't start when warm

[CIverson]

My '03 has been having an issue where it will not start when warm. Started off as longer cranking times (really long). Then a couple no starts, but would start right after.



This changed into a solid no start situation, but will start after it cools down.



When trying to diagnose the first time, I found out I had a bad FASS pump. I figured that was my issue, so I removed it and am running suction off the CP3 for now (new fass coming). This worked for me before w/ prev. lift pump failure without issue.



After removing the pump I drove about 20 miles, went into a store, came out about 20 min. later and no start. I cranked it good and long a couple times. Had to give it a snort of ether to fire and ran fine.



This morning I dropped it off at Diesel Inj. Service. They said they did alot of tests, although some are hard to do w/ no lift pump, and that the injector return rates all seemed normal. And of course the no start is intermittent for them, and they can't reproduce all of the time.



Anyone have any ideas? I was somewhat relieved to hear the injectors seem to be doing fine, but not that they are still trying to figure it out. Gonna be alot of labor in that bill!

 

[sag2]

Did they do the return tests hot? What were the results? It sounds like connector tubes loose or injectors leaking.

 

[CIverson]

Did they do the return tests hot? What were the results? It sounds like connector tubes loose or injectors leaking.

I believe he said they did. I don't think they pulled and tested them, although they are a certified bosh facility, I think they could do it.



If the connector tubes were loose wouldn't there be fuel in the oil? I know the oil level has been consistent, and there is no smell of fuel in the oil, although I have not had it tested.

 

[Wingate]

Once the lift pump issues is resolved, have them check injector return rates again (now that you have good supply volume)

One other thing that could possibly cause this is tight valves. You might consider pulling the valve cover and running the overhead.

 

[JWadford]

Did they do the return tests hot? What were the results? It sounds like connector tubes loose or injectors leaking.

agreed

 

[LWaller]

My 05 was having long crank times when warm and it was the camshaft sensor. Dealer replaced it andtruck starts fine.

 

[sag2]

Loose connector tubes leak fuel back to the tank via the fuel rifle in the head. That is why doing the return test is so important.

 

[CIverson]

Truck has been starting fine since I picked it up friday. Lift pump should be here tomorrow, hopefully I won't have any more issues.

 

[CIverson]

Truck didn't start fine for long. Went a week having to use ether to start when warm.



Brought it back to the diesel shop tuesday. Called this morning and he said the only thing he can find is that the CP3 pump is out of spec. I guess it's flowing 1200cc's which is the max spec. . Also said that it would flow 600 when cold.



Seems to make sense. I just hope it works it's not cheap.

 

[sag2]

Not sure I understand what the shop found. Are they doing a return test and finding the return to be 1200ml in 60 seconds from the pump? Or are they saying the pump will only put out 1200ml max in one minute?

It is hardly ever a bad pump if the return is high, almost always it is connector tubes or injectors.

 

[CIverson]

Not sure I understand what the shop found. Are they doing a return test and finding the return to be 1200ml in 60 seconds from the pump? Or are they saying the pump will only put out 1200ml max in one minute?

It is hardly ever a bad pump if the return is high, almost always it is connector tubes or injectors.

I think he did some type of test to the pump, he did test the injectors, but I believe this was a seperate test.

 

[CIverson]

Looks like I got screwed, drove it home and waited 20 min. no start.



I'm going to re-torque the connector tubes this weekend, and put in some new batteries if I can afford it.



If that doesn't work a new cam & crank sensor, and I'll probably order the tool that plugs the line for an injector and start testing.



Or maybe I should just go buy a 12 valve and toss it in.

 

[JWadford]

still think injectors

 

[CIverson]

I put in a new crank and cam sensor this weekend (when the truck is cold it starts much faster now).



I also pulled out the connector tubes, cleaned everything up and tourqed them all down to spec.



Still no start.



Trying to decide weather to buy the rail caps to test for the bad injector or to just throw 6 remanned ones in.



Sag2, I know your opinion is pretty well respected on the board. All that is left that I can think of would be an injector(s). Can you think of anything else that may be causing it?

 

[JWadford]

to be accurately tested, the injectors need to be removed from truck and put on a bosch test stand, i have seen this on several trucks including my own twice, i even had a so called remanned set give me a no start, they were leaking so bad on the return side it would not build enough rail pressure at cranking speed to start the truck, but if it did start it ran great.