MikeH

Anyone know the timing on a stock '02 HO engine. I believe they increased the timing a little on the HO engine but don't know the numbers. Also, does the OEM map increase timing as the RPM's increase. Quadzilla lets you do this at will and I would think (hope) they don't let you do something stupid. I have an early version Quadzilla XZT+ and leave it in 'Fuel Economy" mode. This Increases timing a few degrees across the board. What I don't know is where normal timing starts and how much my XZT increase it. Anyone?

Oh hell...I could go on for days then. I pulled the batteries from under the hood and have 4 group 31 Marine Batteries installed in the bed in front of the rear wheel wells. Also put a battery selector switch between the two sets of batteries so when we're camping I can use two for power (12 volt + 3000 watt Inverter) while saving the other two for starting only. Along with carrying a spare alternator, I can check that problem off my list of things to worry about.

"When the battery voltage goes from 12.00 to 11.99 the voltage will drop to 8 and chime the CHECK GAGES light" Good to know. I just replaced the alternator which was OEM at ~ 200k miles. It worked just fine so it's in my tool box as an emergency spare. Wonder how long a guy could go with the alt out. I would imagine if the lights aren't on, the radio isn't blasting and AC/blower off you could get pretty far before running out of juice. Anyway, thanks for the heads up.

If I'm reading you right, if the fuse blows you just lost your alternator. Again, other than seeing battery voltage slowly drop off is there any other indication that the fuse has just blown? I have a ScanGauge so I will see a code and would eventually figure it out but will something jump out on the display (CEL, etc) that screams "Go check your alt and replace the fuse too"?

Mike, what goes out if the fuse blows? Alt stops charging, CEL or what?

Yeah...a 6 speed is a PITA around town. We usually jump in the wife's Prius close to home which requires no shifting at all.

One test doesn't mean a whole lot but that was the best mileage I've recorded since installing the camper. I use to consistently get into the low 20's when I had a tonneau cover on the bed. The camper killed that real quick but I wasn't going to gripe at 17/18 mpg going down the hwy. Just found it interesting that with wind advisories the whole trip and us seeming to be headed into the wind most of the time that the mileage would improve. We have a few more road trips planned this summer and fall. I'll let you know if this was a fluke or I'm on to something. For right now I'm leaning towards the lighter weight Amsoil as being the main factor. Nothing else has changed and we had a pretty good load in the bed (water, food, tools, etc). The empty weight on my rig right now is 8300lbs with that custom camper from Caravan.

While I'm not a huge fan of Amsoil I broke down and bought their 75w-110 diff oil. I was going to go with Mobil One 75w-90 but thought the Amsoil would provide a little extra cushion with a loaded truck. We just returned from a ~2000 mile swing through the southwest last week and I kept good track of mileage and fuel use. My rig with camper normally gets around 18mpg on one of these trips. The camper sticks up above the cab and provides plenty of drag. With the Amsoil though I got 20.25mpg. Changing out the differential oil was the only major change made so I have to give the credit to the 75w-110 oil. That's around a 10% improvement in mileage. The real surprise is how much headwind we encountered. I really expected my mileage to drop somewhat but it went up. I'll have to keep track of this on our next trip but I'm liking Amsoil's 75w-110 oil right now. Your mileage may vary!

Sooo...just went over the Quad XZT+ and found I can squirt some electrical contact cleaner right into the circuit board. Pulled and cleaned all the other plugs associated with it and may have found the problem. One of the OEM connectors was missing the little red locking tab. Don't know how I missed that before but that right there would cause an intermittent fault. I shouldn't have been so quick to blame Quadzilla as it's looking like pilot error now!!!

I haven't actually pulled the XZT yet, just have it disconnected. Might just go over the wiring and connectors to see if I can find anything obvious. If it's in the circuit board I'm screwed. Losing the XZT didn't bother me that much as I just ran it in Fuel Economy mode (slight timing increase) 95% of the time. It just occurred to me that boost fooling also went along with the other stuff.

Great!

"Quad XZT is like the Edge EZ model. Way different when you have the Adrenaline. Way more control of everything including timing and fuel mapping" Right...just making the point that it was the Quadzilla throwing the code. My OEM system worked fine once I pulled the XZT from the mix. BTW...now that the Quadzill XZT is gone, along with it's Boost Fooling, what's the max boost the ECM can see before de-fueling? I was getting ~32psi with the XZT in place.

"Might be a bad Quadzilla module and/or wiring too" I started getting the dreaded P0237 low boost code a while back. I had a spare MAP sensor and swapped it out. That seemed to take care of the issue but it wasn't long before the eng light popped back on with the same code. After going over the wiring and cleaning the connectors I decided to pull the Quadzilla XZT+. That was about a month ago with no further problems. I bought that XZT+ when they first came out (2002'ish). Back then we were online with the company and they would email us a new tune to try out. Kinda fun but I rarely used the 'High Power" setting and ran it mostly in the "Fuel Mileage" mode (timing advanced only). Now that I'm back to somewhat stock power I think I'll sleep OK without the Quad.

"it only dumps excess back to the suction side" Loren. my mutant/hybrid DIY home built fuel system created too much pressure (like 26psi) when I first put it together. The advice at the time was to get the pressure back to the magic 15psi so I installed a Glacier bypass check valve AFTER the lift pump and filters which returned the excess fuel to the filler neck...not back to itself or the fuel basket. Not sure how this setup has played in the longevity of my LP or VP but it's been going strong for ~15 years now.

When a rebuilt VP44 is put on the test stand what head pressure (lets say lift pump pressure) is used to fuel the system? I'm going by memory now but way back (like 2000 to 2005 or so) when we were trying to figure out how to best feed this thing one of the Bosch authorized facilities said they applied 14 PSI to the stand. Seems like we all jumped on that thinking if that's the inlet pressure the big boys are using to setup and adjust the pump, that's what we should use on our pickups. 14 psi then became the holy grail of lift pump pressure.

I believe the latest Revision pumps are fairly reliable daily drivers with enough fuel pressure and lubrication added. If you're hell bent on horse power just have the thing P-Pumped and be done with it. The VP44 was just a stop-gap pump between the P7100 and Common Rail. Had Bosch got the manufacturing right at the start (deburring, diaphragm and PSG solder issues) and Dodge started out with a decent in-tank fuel pump (~15psi) we probably wouldn't be having these conversations. As to the heat issue there's two things I do on a regular basis. First is to keep the tank full whenever possible. Especially in the summer a full tank becomes a giant heat sink. Also, filling up more often cools the fuel already in the tank and the process starts all over. The other thing you can do is to just crack the hood after a long hot drive and let the heat out. I don't do this if I'm running over to Home Depot and back. But on long trips where the engine is fully up to temp that hood's coming open when I stop. You have to feel for the electronics in that VP, what with a red hot cast iron engine on one side, surrounded by two large batteries and completely covered by the APPS bellcrank it might as well be in an oven, roasting 'til the engine bay cools off. With the hood open not only is hot air going out the top but cool air is being fed up from the ground. Engineers call this a Stack or Chimney Effect. Will this save you injection pump? I don't know...but it makes me feel like I'm doing something to address the over heating issue. Just a couple of ideas to think about. They're very low tech and require no additional costs or effort.

Mike, I've heard but can't confirm that some biodiesel gets included in almost all diesel fuel delivered in the US. Stations like the Stinker stores here in the NW used to advertise B5 (or some %) for sale but they no longer say that. Haven't figured out if that's because they no longer sell biodiesel or because everyone's adding it and not much of an advertising gimmick anymore. Got this from Car & Driver.com: "According to Edmunds, its production has increased from 25 million gallons in 2005 to 1.7 billion gallons in 2013. Today, biodiesel is blended at a rate of 5% or less into almost all the diesel fuel sold in the United States". It makes sense in that even 2% bio would take care of all lubricity issues in raw ULSD. Just can't confirm that for the fuel here in SW Idaho. To be on the safe side I'm going to keep using a diesel fuel additive.

As little as 2% Biodiesel will supply all the lubrication you need. This is a study done years ago if you haven't seen it: https://www.jatonkam35s.com/DeuceTechnicalManuals/Diesel_fuel_additive_test.pdf My concern is that "new guy" at the fueling docks forgetting to put the additives in the tanker truck and you end up running straight ULSD. I'm sure it rarely happens but people make mistakes sometimes. That could be really bad news for the VP44 so I always toss in enough additive to make sure I'm covered. Overkill I'm sure but my 20 year old pickup with a 14 year old injection pump is still running down the road.

"seeing the working components and the minute travel and physical changes during the cycling actions really allows an appreciation for clean fuel disciplines and additional lubricity in our 2nd Gen platforms" W-T...couldn't agree more. As he mentioned in the YouTube clip everything is metal to metal contact (no bushings, bearings etc) and without engine oil as a lube you're totally dependent on the fuel for lubrication. We already knew that but looking at the inner workings really brought home the need for clean well lubricated fuel. I've always gone a little overboard on additives especially those with the best lubricating qualities. I now mix my own but Opti-Lube Summer Blend is the key component. Safe travels!

Everything you wanted to know about the VP44 Injection Pump but were afraid to ask. I don't know if these guys do rebuilds or what but he knows his way around the pump:

"It seems like it de fuels for a second before jumping right back where it was. Could this be an injection pump issue?" That sounds exactly like the injection pump. Mine did the same thing when I lost my OEM VP44. It would also go into limp mode as yours is doing. I lived with it for ~1 year and had it changed out just before losing warranty. My guess would be you're looking at a new VP44.

That's exactly who I was looking at should I ever need any machining work done. Let us know how they did.

"already got the head shipped off".... Just curious, who's doing the work on your cylinder head?. I noticed there are several machine shops locally (Boise area) but don't know about their reputation.

Yeah...it's done but thanks anyway. I've just never seen such poor electrical work. A simple household wire nut would have been ten times better.

Check! I also pulled that loom along the firewall to the PCM. Same poor construction as the grounds found prior to the W-T mod. 3 or 4 wires squished together with some kind of glue. Unbelievable!