Intermittent No Start

zog · April 23, 2018

I am chasing an intermittent no start/ start stall on a 4/03. It may only happen once a week, but once the truck is started it will be fine for several days. Fuel pressure never seems to be an issue @ 54-55psi. Low oil PSi climbs as it should. I have several recordings, some times it looks as if the icp voltage drops out, other times sync drops out. I have load tested while wiggling these circuits and found no issues. There is a screen shot of the latest recording (all green) where i see no issues, but the truck wouldn't start, A few other screen shots of various no start or start stall recordings, also included is a video of Sync dropping out. I am with out a doubt over looking something, as there have been several parts replaced along the way from various techs, as well as several tests performed that I have forgotten to list here.Any help would be greatly appreciated.

NAX_NO_START.mp4

Keith Browning · April 23, 2018

The ICP voltage looks real crappy even saw tooth looking. Whenever I see THAT on an early 6.0L its usually the HPOP. What has been replaced on this engine?

If it is the pump it's likely the swash plate housing has loosened and is rotating in the pump housing.

And one pump had a cracked rotating cylinder.

KDS · April 23, 2018

I see a few things.

Cranking RPM is too low.

I like to see 150 at a minimum, 175 would be better.

Funny ICP/IPR numbers, Lets start with ICPV KOEO?

Brad Clayton · April 24, 2018

A sync issue, New Hampshire, I'm thinking rust jacking on the cam sensor could be at play also.

zog · April 24, 2018

Keith, I have seen that problem with the pumps cracking as well on the early built 6.0, but couldn't remember if the icp psi pid was saw tooth as well. The other thing that swayed me away from that was how intermittent the concern is, can that create an intermittent concern that only happens cold? This vehicle got a short block and one head back in 2016, but the problem didn't start until a year later. Hfcm is new, front cover and low psi pump, oil pick up tube, several injectors had been replaced over the course of two years, i'm sure i'm forgetting a lot. We installed two new batteries last week as well.

KDS, I felt the rpm seemed low too, but referred back to the Hard Start/ No Start diag sheet that lists 100 rpm as minimum. Icp voltage koeo .17v in some recordings .21v in others definitely low, but during my recordings with the truck starting with out issue they are the same so that kind of threw me for a loop. Made a new recording this morning, the truck didn't start (only a cold start issue), found battery voltage to drop to 10v while cranking.

Brad, I checked the mating surfaces for both the cam sensor and crank sensor are free of any rust or scale. The engine has only been in this truck for 2 years now.

KDS · April 24, 2018

20 minutes ago, zog said:

Keith, I have seen that problem with the pumps cracking as well on the early built 6.0, but couldn't remember if the icp psi pid was saw tooth as well. The other thing that swayed me away from that was how intermittent the concern is, can that create an intermittent concern that only happens cold? This vehicle got a short block and one head back in 2016, but the problem didn't start until a year later. Hfcm is new, front cover and low psi pump, oil pick up tube, several injectors had been replaced over the course of two years, i'm sure i'm forgetting a lot. We installed two new batteries last week as well.

KDS, I felt the rpm seemed low too, but referred back to the Hard Start/ No Start diag sheet that lists 100 rpm as minimum. Icp voltage koeo .17v in some recordings .21v in others definitely low, but during my recordings with the truck starting with out issue they are the same so that kind of threw me for a loop. Made a new recording this morning, the truck didn't start (only a cold start issue), found battery voltage to drop to 10v while cranking.

Brad, I checked the mating surfaces for both the cam sensor and crank sensor are free of any rust or scale. The engine has only been in this truck for 2 years now.

I know what the diag sheet says. At 100 rpm, the compression events are too far apart to effectively heat the air in the cylinder for combustion. You could plug in the block heater for a few hours and see if that makes any difference.

How does the engine sound while cranking?

Have you tested the starting circuit for excessive V drop or A draw?

Try removing the belt.

The ICPV is in range KOEO.

The recordings show a mismatch between V and psi, Usually the sensor.

Might be time for some air testing, get a look at the sensor and wiring and the screen on the IPR. When those early pumps begin to fail, It can pressurize the drive end of the pump and push the seal out.

They will usually leak more air than "normal".

zog · April 26, 2018

It does sound a bit slow cranking, nothing alarming. Checked the starter draw 230 amps, checked both positive and negative cables for high resistance, both are fine. Removed the belt this morning, truck started up with out issue, will try again through out the week.

zog · May 1, 2018

With the belt off, still have crank no start concern present. Keith is there any way to verify that the pump may be the root cause due to internal damage?

Keith Browning · May 1, 2018

With those pumps the ICP voltage is usually the tip off but I had also noticed in recordings made during road tests a lack of power with high IPR numbers and ICP less than desired. The only sure way is to remove the pump and remove the cover and rotating assembly to inspect it.

This screenshot was a bad pump while cranking.

zog · May 2, 2018

Before exploratory surgery on the hpop, do you have any other recommendation.

forddieseldoctor · May 2, 2018

I do believe that if you open the pump you make junk out of it.

And I do agree that your hpop probably has issues.

zog · May 3, 2018

I have no problem letting them know we need to replace the pump, just trying to cover all other less intrusive options first. The handful of early built damaged pumps that I have replaced always had pid readings like Keith"s recording where the saw tooth pattern is on the pressure pid as well as the voltage pid coupled with low psi compared to desired. That being said there is certainly more experienced guys contributing to this forum than me. I just want to make sure that my posts of the recordings I have , match up with a potential damaged pump.

cbriggs · May 4, 2018

I would be tempted to try an icp sensor before tearing into it. Your ICP v recordings look awfully strange.

Keith Browning · May 4, 2018

I kinda agree with Chris about the ICP sensor and probably the pigtail for good measure if not already done. While there is some saw tooth pattern here the signal looks more erratic than anything else. This would be less expensive and less intrusive than a pump right off the start before condemning the pump which you cant rule out. By the way, once you commit to removing and opening up the pump you are pretty much going to have to replace it unless you find nothing wrong and can get it back together without having problems.

zog · May 10, 2018

Got the hpop out and disassembled, looks like some damage to the pump housing where the brass mates up to it, almost like a broken land. The brass component has what look to be the normal "v" cuts, but also have a "u" style marking at the edge of each port which I haven't seen before. The aluminum housing that contains the swash plate appears to have some damage (same as picture above) maybe indicating that there was some play between it and the pump housing. Suspect something went through the pump at some point in its life.

zog · May 10, 2018

The saga continues, after seeing something went through the pump, pulled the oil cooler to inspect the screen, found the oil reservoir less than half full. I have never seen this before, usually they overflow in the valley. Any chance the reman block is porous?

KDS · May 10, 2018

What did the IPR screen look like?

Was the drive end seal pushed out?

This may be a case of gravity.

forddieseldoctor · May 11, 2018

6 hours ago, zog said:

The saga continues, after seeing something went through the pump, pulled the oil cooler to inspect the screen, found the oil reservoir less than half full. I have never seen this before, usually they overflow in the valley. Any chance the reman block is porous?

When you pull the hpop it will drain the resivor. If you look closely the inlet port for the pump is lower than the resivor.

KDS · May 11, 2018

ZOG,

I'll give you a tip.

Raise the rear of the vehicle until the engine is level.

Then when you lift the oil cooler, You won't have a mess.

Add 2 qt's before you put the new cooler back on and you'll cut way down on the cranking/priming time.

zog · May 11, 2018

Good call guys, it didn't occur to me that typically when pulling the cooler i'm not pulling the pump. I hope that the damage to that pump is the root cause of my headache.