OK, here's where I now stand. I replaced all the fuel injectors with a set of remans. I still had P0088 for the rail pressure, but also added a code for misfire on cyl 1 after the replacement. The van now had an off-idle and low boost knock, rough idle, and was kicking the cyl 1 misfire code. I chased down a FedEx contractor I saw driving down the road in a T1N and found where he got his work done. There is a small, local shop in Las Cruces, NM, that specializes in Sprinters (but they don't advertise). I talked to their main Sprinter tech, and he agreed to change my speed limiter to 73 mph, encode the ECU for the new injectors, replace the glow plugs and controller that I hadn't had time to install yet, and diagnose the P0088. He has been working on Sprinters for 14 years, and knew exactly what he was talking about.
The culprit was the Fuel Volume Control Solenoid.
$500 later, the part was on order and the van was returned with the programming work and glow plug/controller installation done... but still had an off-idle and low boost knock, rough idle, and was kicking the cyl 1 misfire code. It was as drivable as before, so it went back into service until the solenoid arrived even though it couldn't utilize the higher limiter speed (the LHM prevented it from getting over 65).
Last weekend, the van died about 3 hours from home. The turbo failed and was dumping oil into the intake and exhaust. I had it towed to El Paso, and began the hunt for a turbo. This ended with me finding an entire parts van in Phoenix for the same price as the turbo, so I bought that instead as an investment for the future. The guy I hired to haul the van home broke down in Benson, AZ, so I had to hire another guy to get the job done. That van arrived yesterday, where I got to work on the turbo.
I also picked up the solenoid from the shop that ordered it so I could install it. This is where the fun began! Two out of the three bolts holding it in had stripped torx heads. I had to disassemble the front of the van in order to get the tools in there to extract the bolts (aka a chisel and a BFH). A simple 10-minute job suddenly became a 4-hour job. I replaced the bolts with (I hope I remember this part right) M5-0.8x20 hex head bolts in grade 12.9, so that they hopefully won't strip in the future.
There was another issue with my van when I bought it. The intake was cracked in the rear, and it was slowly losing coolant. The PO had used cold-weld to stop the leak before sale, and it began leaking shortly after purchase. I bought an intake from a recycler in Michigan, but the first one was damaged in shipment with half of an EGR valve frozen in it. They shipped me another one, and it arrived last week as well. This intake, however, had the EGR bolt holes stripped, as I found when I couldn't get the bolts to stop spinning and there wasn't enough clamping pressure to hold in the coolant after installation yesterday when replacing the turbo. Luckily the parts van has a really clean looking intake on it, so I get to head out this morning and swap intakes again.
I also put the old injector back into cyl 1, and the van now idles quietly and smoothly, and for the first time ever, I completed a trip around the block without going into LHM. Hopefully when the intake is replaced and it holds its coolant, I'll get out on the road this afternoon and put a few miles on it to test everything out. I may even get around to snatching the cruise control switch off the parts van and installing it for programming later (when the faulty injector is returned re-remanned). I will also pull the alternator for bench testing and shelve it for spare parts, along with the A/C compressor, tensioner, idler, O2 sensor, and anything else easy to snatch and store. I'm going to double-check the tire date codes and, if good, I also have another set of Firestone Transforce HTs to toss on when mine wear out.
In the near future, I'll be swapping the rear axle. Mine leaks from the outer seals, and the tech said it's more trouble than its worth to replace the seals. He found it more economical to just swap a used axle in every time. This parts van has already paid for itself. I may begin disassembling the rest of the remaining van for parts sales, but that won't happen until spring. It seems most of the popular stuff is already gone, like the EGR, some injectors, all the switches, the gauge cluster, the passenger seat base (I was hoping this would still be there for myself), and most of the rear and sliding door hardware... but there are still plenty of parts that I can use (and the wiring harness looks to be in much better shape than mine as well).
Happy trails, and hopefully I will have a trouble-free Sprinter for many miles to come after this. Currently at 331,000 and counting.
EDIT: I am adding the shop info into the reviews section
The culprit was the Fuel Volume Control Solenoid.
$500 later, the part was on order and the van was returned with the programming work and glow plug/controller installation done... but still had an off-idle and low boost knock, rough idle, and was kicking the cyl 1 misfire code. It was as drivable as before, so it went back into service until the solenoid arrived even though it couldn't utilize the higher limiter speed (the LHM prevented it from getting over 65).
Last weekend, the van died about 3 hours from home. The turbo failed and was dumping oil into the intake and exhaust. I had it towed to El Paso, and began the hunt for a turbo. This ended with me finding an entire parts van in Phoenix for the same price as the turbo, so I bought that instead as an investment for the future. The guy I hired to haul the van home broke down in Benson, AZ, so I had to hire another guy to get the job done. That van arrived yesterday, where I got to work on the turbo.
I also picked up the solenoid from the shop that ordered it so I could install it. This is where the fun began! Two out of the three bolts holding it in had stripped torx heads. I had to disassemble the front of the van in order to get the tools in there to extract the bolts (aka a chisel and a BFH). A simple 10-minute job suddenly became a 4-hour job. I replaced the bolts with (I hope I remember this part right) M5-0.8x20 hex head bolts in grade 12.9, so that they hopefully won't strip in the future.
There was another issue with my van when I bought it. The intake was cracked in the rear, and it was slowly losing coolant. The PO had used cold-weld to stop the leak before sale, and it began leaking shortly after purchase. I bought an intake from a recycler in Michigan, but the first one was damaged in shipment with half of an EGR valve frozen in it. They shipped me another one, and it arrived last week as well. This intake, however, had the EGR bolt holes stripped, as I found when I couldn't get the bolts to stop spinning and there wasn't enough clamping pressure to hold in the coolant after installation yesterday when replacing the turbo. Luckily the parts van has a really clean looking intake on it, so I get to head out this morning and swap intakes again.
I also put the old injector back into cyl 1, and the van now idles quietly and smoothly, and for the first time ever, I completed a trip around the block without going into LHM. Hopefully when the intake is replaced and it holds its coolant, I'll get out on the road this afternoon and put a few miles on it to test everything out. I may even get around to snatching the cruise control switch off the parts van and installing it for programming later (when the faulty injector is returned re-remanned). I will also pull the alternator for bench testing and shelve it for spare parts, along with the A/C compressor, tensioner, idler, O2 sensor, and anything else easy to snatch and store. I'm going to double-check the tire date codes and, if good, I also have another set of Firestone Transforce HTs to toss on when mine wear out.
In the near future, I'll be swapping the rear axle. Mine leaks from the outer seals, and the tech said it's more trouble than its worth to replace the seals. He found it more economical to just swap a used axle in every time. This parts van has already paid for itself. I may begin disassembling the rest of the remaining van for parts sales, but that won't happen until spring. It seems most of the popular stuff is already gone, like the EGR, some injectors, all the switches, the gauge cluster, the passenger seat base (I was hoping this would still be there for myself), and most of the rear and sliding door hardware... but there are still plenty of parts that I can use (and the wiring harness looks to be in much better shape than mine as well).
Happy trails, and hopefully I will have a trouble-free Sprinter for many miles to come after this. Currently at 331,000 and counting.
EDIT: I am adding the shop info into the reviews section