OK, my truck died. In my last post, I described taking it on the first trip after getting it running again and having it act strange. After completing the rest of the trip, I was going to update that to say that I think it might have been fine - after I activated the Tow/Haul function, it seemed to act just fine. Used a lot more gas, but seemed to shift properly. The only problem was that IPR was around 30-32 at idle, otherwise, IPR was fine. I have the IPR tool on order and was going to pull it as soon as it arrives.

That trip was about 800 miles over two days and I made it home late last night feeling pretty proud of the truck again. Got in this morning, drove about 4 miles, and it just died at an intersection and wouldn't start. Got a wrecker that drove by to pull me into a parking lot where I sit now.

At first, it wouldn't build oil pressure -- while cranking, the oil pressure gauge didn't move. Also, the ICP was at 0 KOEO and then wouldn't get over 300 when cranking. IPR seems OK at 14.8 KOEO and 44 while cranking.

After about an hour, I cranked again and the oil pressure did register on the truck's gauge and IPR was at 860 while cranking, but it still didn't start.

Any ideas? I got a ride home and will be heading back up there in a bit. What should I look for? Maybe this is just one of those hot no-starts, so that when I get back up there it may start? If so, what are the chances of it making it all the way back home?

Wondering if my IPR screen gave out. I've also not replaced the STC fitting (if it has one) dummy plugs, or branch tube (whatever that is) since I bought this truck about 4 months ago.

 

Wow. I hated to see this post. I thought you'd shown that truck who was boss.


Your 2006 does have the STC fitting. How many miles does it have again.


Something is strange with your IPR and ICP reading. With ICP at 300psi, the IPR needs to be closer to 70% because it should close as much as needed to get the 500 psi required to fire the injectors.


Someone correct me if I'm wrong, but the IPR you are reading is the commanded value, not the actual.


So, I think you're on the right track. First, scan for error codes and Cam/Crank/ FICM sync.


Check the following:


1) Unplug the ICP and see if it starts. I don't think that's you're problem, but easy enough to rule out. It will throw an error code that you will need to clear. It will also show around 1500 psi ICP when the pigtail is unplugged.
2) IPR valve. Pull it and check the screen.
3) If I am correct about the ICP and IPR values being screwy, it may be a harness issue. Any oily residue or naked wires on the IPR and ICP? If you get it started, do a wiggle test of the IPR and ICP harness to see if it causes a stutter.

 

500 psi for ICP , .85 for ICPV to start

 

check sync and V-ref

 

[QUOTE=BryanStein


Your 2006 does have the STC fitting. How many miles does it have again.

[I]Not sure. The odometer says 134,000 but the title says 178,000.[/I]


Something is strange with your IPR and ICP reading. With ICP at 300psi, the IPR needs to be closer to 70% because it should close as much as needed to get the 500 psi required to fire the injectors.

*UPDATE* Just went back to the truck. Hoping that it would start after cooling down, but no. EOT/water temps were 80.

Now, the oil pressure gauge does register while cranking. I definitely cranked it hard a couple of times earlier and that gauge didn't move. ICP was 0 KOEO -- isn't it supposed to register something? -- but it did go to 1267 during cranking with IPR at 57.8. Now, I'm not sure if there wasn't just a ScanGuage user error when I got the low reading earlier

The battery started getting weak, which is surprising because I didn't crank on it that long this afternoon and it'd had several hours to recover. Coming off that road trip, the last 8 hours at night with lights, I wonder if my batteries are weak enough to cause it to die? Not likely, I guess. It was cranking strong when it first died.

First things first. Gotta get it towed home and charged up. Confirm that it's getting fuel, etc.


Someone correct me if I'm wrong, but the IPR you are reading is the commanded value, not the actual.

Not sure. It's the IPR reading on ScanGuage.


So, I think you're on the right track. First, scan for error codes and Cam/Crank/ FICM sync.

Strangely, while driving yesterday and bored, I checked the codes and there was 4. Now, there's none.

The ScanGuage synch gauge shows it syncing up after a few seconds of cranking.


Check the following:


1) Unplug the ICP and see if it starts. I don't think that's you're problem, but easy enough to rule out. It will throw an error code that you will need to clear. It will also show around 1500 psi ICP when the pigtail is unplugged.

Did that, although I didn't check the psi while cranking. Haven't checked whether it threw a code.


2) IPR valve. Pull it and check the screen.

That was my plan for this week. Ordered the socket last week but it hasn't arrived.

3) If I am correct about the ICP and IPR values being screwy, it may be a harness issue. Any oily residue or naked wires on the IPR and ICP? If you get it started, do a wiggle test of the IPR and ICP harness to see if it causes a stutter.

OK.

Thanks for helping. I'll keep post another update when I get it home and charged up.

 

The sync seems to be OK according to ScanGauge. I get a 1 after cranking for a few seconds. My VREF seems fine - 5.0 on ScanGauge everytime I've noticed it.

 

Set your scangauge refresh rate to fast. I am questioning the 300 psi icp and only 44% ipr.

 

I would do the STC fitting, standpipes and dummy plugs for starters as they are known to fail and at least you will eliminate those as a possible issue.

 

yes, and I probably will. However, I don't know that those haven't already been replaced. A mechanic told me that he can tell that the heads have been off before from some marks a previous tech left on a head bolt. I hate to tear off the top of the engine and find it already has an upgraded fitting.

I did get the truck home just a few minutes ago and will put a charger on it tonight. Start going through a diagnostics process tomorrow.

 

Yeah, not sure why I got that. It could be me or ScanGauge messing up. Since that reading, the other readings have all been well over 500psi.

I'm also puzzled why the truck's oil pressure gauge didn't register any pressure for a couple of good long cranks, but now it does. Does the truck cooling down have something to do with it? Does that point to any specific cause?

 

You can tell if the pipes and plugs have been updated by removing the valve covers and checking the size of hex bit required to remove them , if they take a 10MM hex they are original, if they take a 12MM they are the updated.

 

Great info. I've already taken them off several times when I was replacing injectors, so I'll go see what size hex I used.

I'm thinking they were updated because I definitely updated one standpipe myself and they both use the same hex.

 

I think what happens is that it takes about 7 seconds or so for the oil pressure gauge to register, and I just didn't crank enough earlier. Does that sound normal?

 

OK, just to confirm, I took the secondary fuel filter out and cranked it to see fuel pumping. Seems to work just fine (brand new pump should).

Then, I took the oil filter and cap off and cranked again - it took a few seconds, but not more than 10, to fill the bowl. Does that, and the fact that it moves the truck's gauge when cranking suggest that I don't have a low pressure oil leak?

I got ICP - well over 1000 when cranking. I got sync after a few seconds of cranking. FICM voltage is fine. It doesn't start with the ICP sensor disconnected. It passes the bubble test.

I do have a P0106 code for the MAP sensor - could that cause the no-start?

I'm still guessing its the IPR - recall that it was around 30 at hot idle. It does register 14.8 KOEO, and +50 when cranking - could it do that and still be bad? I'm stuck waiting for the IPR socket I ordered to show up.

 

Having the Map hose or connection off might do it never know what the Computor try's to command, did you take those off for some reason? or maybe cracks in the Hose it self . What was the ICPV at cranking?