I’ve mainly been quiet here because I’ve been frantically trying to get the months-old boost problem on Junior solved enough to go to Portland while it’s still, you know, SUMMER. It’s been a constant cycle of frustration as I fix thing that clearly needed fixing, and yet the problem persists. The Good News is that nearly everything I’ve fixed was actually worn or broken somehow, and most of those things only need to be refreshed every 50,000-200,000 miles. So once they’re fixed, I should be good for a very long time. The Bad News is that time is a wasting, and my ability to take an extended trip to the west coast and actually have the ideal weather I’m seeking is bleeding away with every day that passes. It’s been very hard to keep my spirits up, facing another day of working on the van in the 97-101 degree heat, frequently without shade, and get no closer to having a functional vehicle.
On the RV side, I have pretty much everything I need for a fully off-grid urban stealth camper, including 400 watts of solar panels, a solar charge controller, a 420 Ah Interstate deep cycle battery bank, both an induction and propane stove setup, a 12V sink pump and reservoirs, a Maxxair vent fan, etc. I’ve made some headway figuring out how to get the panels on the roof, and maybe one blessing in disguise is that I might actually have them up there before I leave on the trip. It will certainly be easier to sleep without all those solar panels on my bed!
The Latest Theory is that the exhaust back pressure is too high. I’ve been focusing on the air intake plumbing, and have just about run out of things to replace. However, back pressure from a clogged catalytic converter or diesel particle filter could also cause the computer to disable the turbo, not because the turbo input path is leaking, but because the correct amount of pressure there is meeting excessive blockages on the way out. This would lower the effective turbo pressure for a given set of engine variables, possibly causing a low boost code.
To that end, I’m going to try disconnecting the exhaust after the turbo and go for what will probably be some *very* noisy and stinky test drives. If the low boost problem goes away under those circumstances, then I know I’ve found my problem.
Wish me luck.