Might wanna try the Hyundai Purge Control Valve. You can get them for as little as 10-15.00 on Ebay in an OEM Hyundai parts box. The good old Diehard Platinum was actually made by Odyssey back in the day. Sadly Sears discontinued the Platinum series and our chance of getting an Odyssey a little cheaper.

I just get the deep cycle RV battery from Sams Club now for my D2's.

The SAI pump being loud is probably the filter has all but disintegrated, the 3 rubber mounts have busted. When it operates it pumps cold air into each SAI stack attached to each head. The small solenoid valve allows a vacuum to then operate the stacks and open them. That allows the cold air to enter the exhaust. Then once it's finished the solenoid valve releases, the vacuum goes away, the stacks close, and the pump turns off. Pretty simple system really and BMW used it for years. Main issues with it are leaks at the vacuum lines, broken main hard line from the pump to the metal hard line, broken rubber mounts, and sometimes the pump will throw in the towel.

P0441 is usually the Purge Valve itself, bad threads in the fuel filler neck which cause the gas cap to click, but it's actually not sealed 100% which then causes a small leak in the system. You can clean the threads in the filler neck with a scotch brite pad.

 

Did you crimp or solder those terminals?

 

So the linkage let go on my truck while I was descending a steep hill in low range with HDC activated. Had not used the linkage in almost a year but last time I used it descending Mt Ascutney the low range and HDC worked flawlessly.

Upon reaching the bottom of the hill I shifted the transmission into neutral while maintaining a speed of between 5-10mph. Then I deactivated the HDC and proceeded to shift back up I to high range. I noticed some strange mechanical clunking noises periodically. The linkage appeared to let go and the high/low shifter feels almost loose; by this I mean that when I try to push or pull the high/low shifter in high or back in low, it feels effortlessly. I tried shifting into lock then unlock and there is still resistance as you would expect but no resistance when trying to shift between high and low. Despite pulling the shifter into the high position the truck is still in low range.

Last year I drained the transfer box. Cleaned the inspection cover plate and applied a new bead of sealant around the perimeter. Refilled the transfer box with Mobile 1 gear oil. Besides small droplets no known major leaks from the transfer box. Recently the transmission was removed and professionally rebuilt with a master rebuild kit. As far as I know the transfer box was not torn apart or altered.

Iam surprised as the truck is rust free. In any case I dropped the truck off at a local shop over a week ago and they are stumped so far. They checked the cdl locker linkage and found no issues. I told them to inspect the high/low linkage. Is this a common failure point on the late model Discovery transfer box? Could the solenoid cause these symptoms or is a broken linkage the most probable culprit? Could this indicate that the transfer box itself needs a rebuild?

 

You can see the cable from underneath - passenger (right) side. Get a good light and shine it up there and have someone move the hi low lever. You should be able to tell if that is still functional.
It could be the connector or cable, with luck.

 

I had this happen this summer and a connection in the linkage had snapped that controlled the hi/low. I could still lock the case but I was luckily stuck in HI which made the drive home much less complicated. Pull the center console out and it's super easy to see from the top. I could not see the broken piece from underneath.

 

Your shop should be able to figure this out. Put the truck in the air. Inspect the linkage. If it looks good, work the linkage into Hi/Lo and confirm the transfercase has shifted into Hi/Lo by spinning the wheels.
If it's not the linkage it's something inside the transfercase.

 

Agreed that it should be an easy task to diagnose what went wrong. Especially since they had to remove the riveted access panel thus giving them access to the top end from inside the truck. The truck has been parked at their shop for 3 weeks now. No updates. No progress. I gave them all the information as well as technical data and diagram of the transfer box and pictures of the linkage so they know exactly what and where to look for. Told them I need to know what broke asap so I can source it. Be it a linkage assembly or a clip or the hardware. Let down.

My girl and I have 2 vehicles now between us. I bought her a 2004 Honda Accord EX, 4 door with the 6 cylinder vtec afew months back. Her first car. Same .mileage as my D2. Has some rust. Power steering lines were rusted through, rear brakes shot and turn signals for right side not working. It's been one thing after another. The front passenger cv axle snapped while we were in central NH visiting family. We got stranded because we left the Rover down on the seacoast. Ended up leaving the Honda at the shop to have the work done. 2 weeks later we drove back up there to pick it up then the linkage failed on my truck. Cold and pressed for time I opted to drop the truck off at the same shop and have them deal with the linkage. That was 3 weeks ago. Sucks.

 

The shop finally made some progress today. They said the linkage does not appear to be broken or bent but that unclip that secures the cable to the transfer box on the top end had broke. They replaced it and put the access panel back in place. Upon attempting to shift the linkage from low to high they said the linkage is really stiff. I asked them if they had the transmission in neutral and they said yes but that the truck is in the shop as they try to engage high range. I told them to lub the linkage at all the points then to take it out on the road and maintain a speed of around 5-10 mph, then shift into neutral and attempt to disengage low range. They will get back to me.

Not sure of a stiff linkage is an indication of bad linkage or bad transfer case or just lacking some lub. Any thoughts?

 

Much has happened since I last updated my thread. The shop finally got around to fixing the low range linkage. Took them just over 3 weeks to get the work done. All it was just a slightly bent cable. I also needed a new clip. I also had the shop flush the heater core while it was in the shop since I dont have access to high pressure water.

Since then I've been busy making the truck road legal with regards to NH state inspection. It's been several months since I performed the head gasket job and we are leak free with regards to the cooling system and the heater blows hot air again (though I still want to improve heating system). Still have a couple oil leaks. One up front either at or above the oil filter. I've been dealing with this leak since I bought the truck and have not pin pointed the source. It also appears that the rear main seal is leaking some oil. Sucks because I had the transmission removed and professionally rebuilt in 2019 and the shop that performed the work made no mention of a leaking seal. For now I'm trying out Lucas oil stabilizer/stop leak. Put in a quart today. Hope it buys me some time.

Since then I've been tinkering on the steering system. Recently the high pressure line failed and there is a new leak that appears to be coming from atop the power steering gearbox but I've tightened every nut and bolt and the bleeder to no avail. The power steering leak is less of a leak and more like a constant moist layer. Takes weeks for the fluid level in the ps reservoir to drop down mudownt all.

My ball joints, tie rod ends and CV axle boots all had broken rubber boots and were bad so I had a shop replace the upper and lower hub ball joints, cv boots, axle shaft seals and I had them replace the ABS shuttle valve switch and perform THE FIX" to the abs block. Needless to say no more amigos and the abs system is working as it should.

I've wired in a aftermarket touchscreen rear view mirror complete with front and rear cameras that record everything 24/7. Makes reversing and hooking up the trailer much easier.

Today I replaced the drag link and track rod. Thought long and hard about going with the aftermarket HD steering rod kit but in light of many other folks bad experiences with the aftermarket "budget kits" and considering how many years of life and reliability I got out of my factory rods, I decided to stick with genuine steering rods. Got a reasonable deal on them from Rimmer Brothers. They were stupid easy to replace/insta. The new rods appeared to be the same length as the old rods so I just installed them and was able to drive to a shop for a alignment. Got the alignment all done and the most all of the suspension system is updated.

Finished the day at another should getting the old girl inspected. Apparently NH just updated its safety inspection requirements and now shops are much more **** about ****. No tint of any kind in your front windows (mine had tint), no scuffs, cracks, knicks or yellowing of the headlights or taillights etc. Ended the day with a blue inspection sticker and I'm happy.

Next line of business will be finishing up the power steering system. Gotta resolve that leak. Rear bumper needs to be replaced. Hoping to find a undamaged rear bumper cover to use until I can get my hands on the RTE hd rear bumper. The front headlights do have knicks in them and are yellowing. I had the shop buff them out again but it won't last long. Gonna buy new euro spec headlight assemblies. Need to update the brake lines to the extended ss lines. When the truck is jacked up the wheels hang so long it puts excess strain on the aging brake lines. Gotta get the rear main seal replaced. And I'm thinking about getting the aging transfer case rebuilt and the axles examined and rebuilt if need be. If not just reseal the pumpkins and call it good. Also looking to retrim the interior. I'd like to pull the leather off the front seats and swap in factory other seat covers and I'll be replacing the lower foam seat pads and heated seat components. Then I want to replace the alcantra front door inner trim panels with UK versions.