Build '95 4runner TDI swap

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MoabPorkChop said:
I do have a harness from fast forward. I'm guessing that its plug and play but I havent looked at it and dont know where all of the sensors are. I have been planning this swap for about 2 years and slowly buying parts I knew I would need but I the wiring is still in a pile.
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It's not exactly plug and play but it's 100% better than going from scratch.

His harness is labeled on the outer wires leading to to each sensor as to where it goes.
 
I started in on the wiring and ended up finishing the coolant hoses.

I started to lay out the harness on the engine and realized that I should get an idea of how other people did it or how fastforward planned it.

Where did you put your VW ecu? Do you have pictures?
dohcdelsol93 said:
Other than wires for your gauges, alternator exciter, AC power button (might not work with ac amplifier Toyota system, I have documented how I got around this) and starter button you don't need any engine harness wires in the engine bay. Marking these with tape when removing as well as what wires go to your horn, lights, possible brake reservoir sensor will be about all that's left from the factory yota harness in the bay.
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MoabPorkChop said:
I started in on the wiring and ended up finishing the coolant hoses.

I started to lay out the harness on the engine and realized that I should get an idea of how other people did it or how fastforward planned it.

Where did you put your VW ecu? Do you have pictures?
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I have a build thread on here, in this section with some 2 years of pics. Check it out and if you need any specific pics, my TDI yoda is my DD so I can take more if needed.

My ECU is mounted under the glove box passenger side. The ECU harness to the engine goes out where the original engine harness exited.

IAT, egt, alt, fuel temp, coolant temp, glow plug, injector harness, cam and crank sensors... I think that's all from ECU to engine.
 
dohcdelsol93 said:
My ECU is mounted under the glove box passenger side. The ECU harness to the engine goes out where the original engine harness exited.

IAT, egt, alt, fuel temp, coolant temp, glow plug, injector harness, cam and crank sensors... I think that's all from ECU to engine.
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This is what I was thinking. Thanks. I started to find all the connections on the engine but was having trouble with connecting the round plug that goes on the back of the head. I cant see it very well because of its position but I can slide the plug on and it feels like it slides in but it is slightly loose and doesn't lock in position. I'm a little stumped on that one.

then the productive procrastination kicked in and I finished the cooling. Except should I put the coolant temperature sensor in the upper hose or the lower hose?
 
That plug lines up with 8 pins if i remember correctly. It will only slide in one direction and the tabs have to be aligned perfectly. I think it turns a half turn clockwise (ccw looking front to back) to lock. It is a little bit of a bear if you haven't removed to installed it in a while. Make sure it's in the full unlock position before attempting install or you'll never get it on.
 
I started to read your build thread. Thanks, It will help a lot. I haven't read much yet but I can see how you have all the answers to my questions.

Matt.
 
My harness has a connector labeled G507. What I have found about it is it measures Turbo intake air temperature (egt) and there was supposed to be one on my original exhaust manifold but there isn't. There isn't one on my new exhaust manifold either.

Also one wire is labeled ALH and I don't know where it goes. This is a BEW.

I got the engine wiring harness connected but these last two have me stumped.
 
Also...Where the hell does this go? I can't find a similar compatible plug. I'll figure it out but none of this is intuitive for me.

IMG_1094.webp
 
I think the ALH wire may actually be ALT. That makes more sense but I'll have to check in the morning.
 
MoabPorkChop said:
My harness has a connector labeled G507. What I have found about it is it measures Turbo intake air temperature (egt) and there was supposed to be one on my original exhaust manifold but there isn't. There isn't one on my new exhaust manifold either.

Also one wire is labeled ALH and I don't know where it goes. This is a BEW.

I got the engine wiring harness connected but these last two have me stumped.
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I didn't think the BRM had a g507, the BHW did on mine. I'd send an email to Dave and see what he says, he's always been terrific with after the sale tech support from my experience.

A further search reveals ID parts selling an egt or thermocoupler sensor for the BRM, if it's there it's going to be in the exhaust manifold.
 
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I didnt even think about it being for the glowplugs. It would be a challenge to get it outside of the passenger compartment.

I have been reading more of your thread. You did a lot more than I am trying to do. 👍

I can write to FF also. I don't have any criticism of this harness and I cant imagine where I would be with out it.
 
I had my fenders off to do the wiring/paint. I removed the passenger side rubber body grommet and split it on one side if I remember correctly I then ran all the wires through the center. I taped it back up, I can't remember it it was a little window adhesive or decal adhesive or even some butyl tape along the cut and tapped everything together before pushing back in.

I wish I could remember in better detail, it's been a few years.
 
I emailed Fast Forward about the mystery plug and he replied back with in 15minutes.

You were right it was the glow plug relay. While I was searching I found this post and complete understand his confusion. I swear I am a relatively competent person but sometimes I can stare at something and not see it.
Screenshot 2025-10-31 194646.webp
 
Don't feel bad. I ran into a few sensor issues as well that required email support from Dave. Luckily Dave knows TDI motors well and is quick to respond. His after the sale support has always been stellar in my experience.
 
Off on another tangent...did you build a vacuum manifold for the n75, brake booster, vacuum pump, and vacuum ball junction?
 
I don't have a vacuum manifold, I attached the brake booster to the large port on the tandem pump just as it was on the Passat. The n75 and vacuum ball are then attached to small port coming from the tandem pump as found Passat as well.

I can post up a picture if that doesn't make sense.
 
dohcdelsol93 said:
I don't have a vacuum manifold, I attached the brake booster to the large port on the tandem pump just as it was on the Passat. The n75 and vacuum ball are then attached to small port coming from the tandem pump as found Passat as well.
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I will have to take a closer look when I get home tomorrow.
 
I have been slowly collecting parts for the fuel system and decided to put the EGT sensor in the exhaust. I ordered the sensor for this engine and was going to drill a hole in the exhaust manifold but go stumped my the fitting I would need. It looks like I need to drill a hole with a step in it and somewhat blind threads. Any ideas? Or maybe there is supposed to be a clip that keeps the sensor from sliding in to the exhaust?
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