Builds Another Prado in Montana

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I’ve been working on sorting out the rats nest that was the glove compartment and LH side of the engine bay. Due to the size of the VW wiring harness, the glove box didn’t fit anymore and I had planned on leaving it out and making an electrical panel to mount in its place. In the end I decided against that plan and just trimmed the back corner to clear the harness. It went from this:
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To this:
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And finally this:
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I still have some work to do buttoning up the gauge pod and eventually adding a stereo, but other than that the dash is pretty much together.
 
In the engine bay the wiring for the MAF sensor and the turbo controller needed to be extended to reach over to the other side of the engine. I was able to use some of the protective casing and fittings from the old VW harness to make it look a little nicer.
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The finished harness:
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All buttoned up!
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More items checked off the list! Bought a Longfield driveshaft spacer for the front now that the transfer case has moved back 1.5 inches.
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I also built a mount for the VW fly by wire throttle pedal:
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I would like to figure out a way to hook up the manual throttle knob and cable, but mine is seized up and the plastic housing stripped out, so that project will have to wait for a later date. It looks like the cable from a 76, 78 or 79 would work if I made an arm that attached to the side of the pedal.
 
Been picking away at a few things over the past couple of weeks. With finals over I am ready to get this finished up! I got the stock TDI downpipe cut off the turbo flange and tacked on to a new flange in the correct position. Unfortunately it is only 2" pipe, but I should be able to fit 2.5" starting just after the elbow.
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I also got all of the wires for the Auber gauge run and hooked up.
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Which brings me to this evening. First I tried filling the transmission and transfer case, but discovered I was just a little short on gear oil. The transmission is full but the transfer case still needs topping up.
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Then I went to put oil in the engine but remembered that I hadn't attached the end of the turbo oil feed line to the block, and was missing one of the crush washers for the banjo bolt. After a futile search through all of the boxes of parts and bins of miscellaneous hardware I decided to just make one out of some aluminum.
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I annealed it to make sure it would seal properly.
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This was followed by another futile search of the shop, this time for a case of engine oil I was sure I had bought, but probably ended up going into my Jetta. So I turned my attention to finishing up a couple of wiring connections and then fretting over what I may have missed. Finally, terrified of a cloud of smoke or some sparks, I put in the battery and hooked it up. Everything was a fine; the dash and dome lights came on, and when I turned the key the Auber gauge and ECU tune loader sprang to life. I spent the next 15 minutes programming all the settings in the Auber, including the non/off temperature settings for the radiator fan, which also worked.
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So now I have a long list of things that I need to purchase or remember to bring to the shop. If all goes well I should be able to try firing it up later this week!
 
Congrats! That is a major milestone! Engine sounds great. I look forward to hearing your impressions after you drive it.
 
Really looking forward to driving it too, but am anxiously awaiting a new clutch hose to make that possible. So far everything is working with the exception of the tachometer, though I believe the tach signal output from the ECU may have been deleted when the engine was tuned. I’ll have to contact the tuning company to confirm.

I’ve had leaks of every kind except oil; one of my coolant hose connections wasn’t tight enough, and there was a geyser of power steering fluid. When I first went to start it I could get it to crank but it wouldn’t fire, a little troubleshooting revealed that one of the wires had come off the ECU power relay. My pyrometer read nearly 800F at idle, I discovered I had programmed it for an R type thermocouple rather than a K type. All good now.
 
Not too much happened today, still waiting on the clutch hose. I did have to trim a bit of the transmission crossmember where the vacuum shift housing on the transfer case touched, and I'm still chasing a small coolant leak on the back of the engine. I also discovered that the linkage for the transfer shifter is now a little too short, so I got to practice with a new Oxy/Acetylene torch.
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The clutch line arrived on Wednesday and I set to work getting the clutch bled. After 4 hours or more and no progress it was time for a rethink. The system had started to build some pressure and then completely quit, the pedal would go to the floor. I was on the verge of ordering new master and slave cylinders when my brother convinced me to pull the master and see if we could find something wrong with it. Once we had it out we discovered that the cylinder bore and piston were the same size as a T100 master cylinder I had. We swapped the internals, reinstalled the master cylinder and the clutch worked great. I still have some adjusting to do but it does the job.

Early on Thursday morning, at about 12:30 AM, the Prado moved under its own power for the first time in 2 years, 2 months, 3 weeks and 3 days...819 days total. Took it for a quick test drive (about 1/8th of a mile) and realized the rear brakes were completely locked up. I ordered new rotors, pads and calipers, should be here next week. The other issue is that the engine doesn't seem to be building boost; there is very little power and the EGT's don't get over 900F. I haven't been able to accelerate past 3rd gear in high range yet. I believe there is an issue with the vacuum system controlling the turbo vanes, perhaps a vacuum leak somewhere. Another product of the late night was the failure of my brother's shop door, so the Prado got to act as a door for the night!
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Still no luck on diagnosing the lack of power issue, I have a VW/Audi mechanic friend who is going to bring his VCDS by and have a look at it in the next couple of days, hopefully that will shed some light on the problem. In the meantime, I tore apart the rear brakes to replace the wheel studs. Several of them had broken so I thought it best to replace them all. There was a significant amount of dissimilar metal corrosion on the hub where the alloy wheels fused to the rotor, I had to chip it away with a screwdriver.
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I disassembled the emergency brake so I could get the studs out without removing the axle and pressing the backing plate off. A tie rod end puller works great for pressing the studs out, just get it tight and give it a whack with a hammer.
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Reassembling the emergency brake with the axle flange in place was a royal pain, there is very little space to work with. I found that compressing the brake shoe retaining springs with small zip ties meant I didn't have to fight the springs. Once the little retainer cap was on I could just snip the zip ties.
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While I had the Prado up on the lift I figured it was a good time to replace the rear shocks. I've had a set of OME sitting in a box for a couple of years now, and the original shocks were completely worn out.
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I can't wait to try that spring compression trick. That solves a major source of drum brake frustration - even for ones that don't have an axle shaft in the way.

I've always hated doing drum brakes for the same reason. When the zip tie idea occurred to me I couldn't imagine why I'd never thought of it before.
 
A bit more progress made today with the installation of a new OME steering stabilizer. The axle end was stubborn, but nothing a bit of heat couldn’t cure.
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My friend from the VW dealership was able to swing by and hook up his VCDS computer, there were 5 fault codes, but nothing that would cause the lack of power issue. He cleared the codes, and suggested I try a new MAF sensor. Luckily my brother recently bought a 2001 Jetta TDI, so we just swapped MAF’s and it made a huge difference. Lots of power, good turbo noise and plenty of boost lag 😁. This was with the stock 90hp tune, I can’t wait for my new Stage 4 150hp tune! None of the previous codes showed up again either. New MAF sensor is on order, I can’t wait!
 
Time for a long overdue update. I replaced the MAF sensor and went for a test drive, it felt great and I got up to about 100 km/h, into 5th for the first time. Later that evening I hooked up a boost gauge and took it out again to see what kind of boost it was running with the Stage 1 tune, and it went into limp mode again; no boost, no fuel, couldn't accelerate once I got into 4th gear. After some troubleshooting I found that the stop screw for the turbo actuator had come loose and moved to maximum extension, stopping the actuator from opening the turbo vanes at all. Once fixed the limp problem still remained, as I had no way of clearing the codes in the computer. I broke down and bought a VCDS cable and software, I figured it was worth it since there are now 4 VW TDI's in the family.

Fast forward to last week, the VCDS finally arrived but I was occupied with a new, and very large, project (like I need another one of those). It's a 1965 Thiokol 601 Snowcat:
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Yesterday I got the VCDS up and running, there were a handful of codes that I cleared but one kept coming back: failed MAP sensor. Since I need to replace the current 2.5 bar unit with a 3 bar to run a Stage 4 tune I went ahead and ordered one. Hopefully no more sensors fail on me!
 

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