With all the teed-off circuits it can be a little difficult to follow the flow of coolant in the system at first. Even still, imitating the Passat system seems to be reasonable enough, and there are plenty of leftover hoses to use.
Where the five-cylinder uses a thottle cable and vacuum-line mechianism to control speed, the TDI uses drive-by-wire. Some minor fabrication is needed to make the accelerator pedal work, but you get cruise control for free.
Details on getting filtered air into the engine, moving it around a bunch, and getting it back out (well, kinda). This part requires some creativity and fabrication, depending on your goals. There's also a ton of different ways to do it. Here's how I did it »
Getting started with wiring is the most difficult part for this swap. Because there are wires everywhere, there's no clear starting point, but don't let that discourage you. Just pick something and go for it; everything else will fill in from that point. I've chosen to begin by pulling the engine wiring harness from a '96 Passat, labeling it, and going from there.
Hooking up the air conditioning, power steering, exhaust, coolant lines, vehicle speed sensor, etc. While we're fortunate to be working with parts from the same general Volkswagen era, there are of course some modifications that must be made.
In this post I'll cover the removal of the beast that is the 2.5 5-cylinder AAF engine, modifications to the drivetrain, and installation of the 1.9l TDI.
This is the last of the fun part, so read more while there is still hope.
A giant box of parts finally arrived. While it would be too simple for everything to simply arrive correctly, the rebuild can now commence and a big part of the puzzle can be solved. Some additional light modifications must be made to mount the new ABL parts on the 1Z engine.
Why you shouldn't deck a TDI block (or, really, any block) on a rotary broach. Continued trouble with piston protrusion »
Using oversized pistons on your TDI rebuild? Plan on decking your block. Find out why »
With the block prepared it's time to install the rotating assembly. This is where I hit my first snag with the reluctor wheel and regrets I didn't have the machine shop weigh my new pistons while they had them. Take a look.
I was able to get started assembling the engine due to a nice day outside. With the block prepped and painted, block modifications need to be made to install the T4 engine mounts and dipstick. Once I sourced a 14mm drill bit from Amazon this was a fairly straightforward task. Read More
A transmission is being imported. The block is back from the machine shop. Rebuild parts have been received. I'll be updating the progress of converting a 1993 Volkswagen Eurovan (T4) to diesel power. While this has been a dream for a while, take a look at the Backstory to see the impetus for the begining the swap now.
