'95 4runner TDI swap (17 Viewers)

[MoabPorkChop]

I am swapping a VW TDI into my 2nd gen 4runner and need some help knowing what wires I can take out of the engine bay and not affect the functionality of the truck. I want to keep everything inside the cab stock.

Right now i am following each wire back to its source but this is slow. I have read that the electrical for the chassis and the engine are completely separate but have no details. I would love to just pull entire harnesses out rather than one wire at a time.

Any help or direction would be great.

Thanks, Matt

 

[dohcdelsol93]

This has so many variables but to keep it simple:


You can weed out every wire running to the original engine from the ECU except the alternator excite wire, the oil pressure gauge wire and water temp gauge wire.

You'll need to reuse your yota sensors/adapt them to the TDI engine to make your dash gauges work.


This will involve removing your dash, fenders and associated parts to get the harness out of its anything like the 1st Gen.

Probably best to figure out your TDI wiring, get the engine installed where you want it as there may be a few wires from the original harness you can tie into your TDI harness for a more clean/factory look.



The 1st Gen has a harness coming from both sides of the bay and both sides have wires going to both the engine and lights. In your case there's also probably an aux 12v AC fan you'll want to reuse if you're keeping AC functional.

While the dash it out you can run your brake and clutch switches to the ECU. The ECU also wants to see speedometer input, at least my BHW does.

If keeping the AC you won't use the factory Toyota AC amplifier, or at least I didn't want to fool with figuring out how to make it work so I installed a low/high pressure switch and 30 amp 5 prong relay to run my ac compressor and ac fan. The blue ac button on the dash still turns my AC on and off.

You'll need some sort of adapter to make your tach work. Dakota digital and fast-forward automotive are two that should be able to help you with that but there may be more out there by now.

Most of the VW ecus to turn on and off via the alternator warning like so keep this functional.

Using a wiring diagram of your yota you'll want to wire in the CEL light from the VW ECU and find a spot for your glow plug light.

 

[MoabPorkChop]

This has so many variables but to keep it simple:


You can weed out every wire running to the original engine from the ECU except the alternator excite wire, the oil pressure gauge wire and water temp gauge wire.

You'll need to reuse your yota sensors/adapt them to the TDI engine to make your dash gauges work.


This will involve removing your dash, fenders and associated parts to get the harness out of its anything like the 1st Gen.

Probably best to figure out your TDI wiring, get the engine installed where you want it as there may be a few wires from the original harness you can tie into your TDI harness for a more clean/factory look.



The 1st Gen has a harness coming from both sides of the bay and both sides have wires going to both the engine and lights. In your case there's also probably an aux 12v AC fan you'll want to reuse if you're keeping AC functional.

While the dash it out you can run your brake and clutch switches to the ECU. The ECU also wants to see speedometer input, at least my BHW does.

If keeping the AC you won't use the factory Toyota AC amplifier, or at least I didn't want to fool with figuring out how to make it work so I installed a low/high pressure switch and 30 amp 5 prong relay to run my ac compressor and ac fan. The blue ac button on the dash still turns my AC on and off.

You'll need some sort of adapter to make your tach work. Dakota digital and fast-forward automotive are two that should be able to help you with that but there may be more out there by now.

Most of the VW ecus to turn on and off via the alternator warning like so keep this functional.

Using a wiring diagram of your yota you'll want to wire in the CEL light from the VW ECU and find a spot for your glow plug light.

Thanks dohcdelsol93,

I have a tach adapter from fastforward and a stand alone harness. My dream was to completely remove the engine wiring and ecu then stick in the VW engine harness w/ecu. I wasnt sure if the harness that runs back through the firewall is just engine control. I want to keep the cruise control so I am keeping track of what i believe to be the speed sensor connected to the transfer case and the backup light switch wire but other than that its turning into spaghetti.

I am cleaning up the engine bay so I can stick the TDI in and try to get it running and moving the truck. Next will be making everything work. I waited until it started cooling off so I could figure out the ac next year. I figure the heater is going to be easier. I just didn't want to shoot myself in the foot first.

Matt.

 

[MoabPorkChop]

I pulled every wire that went to the ecu and had to go through it three times before I realized that the alternator wire isnt part of the engine harness it is connected to a sub harness that seems to be part of the front lights???

I am completely confused by the power steering system. I seem to have two steering boxes both with fluid from the PS pump...and it looks like the brakes are connected to the system also. I cant imagine that they are but Im not sure what is going on.

Main box from the steering shaft

Second box from connected to the first by lines running across the engine bay
Second box is connected to the PS pump on passenger side of the engine

This is where it gets weird. The small lines from the second pump seem to connect to the brake lines
Am I correct or completely nuts?

 

[gnob]

the second box is your abs unit.
go on ebay or TIS and get a factory service manual and ewd for your truck.

 

[dohcdelsol93]

The steering adapter shouldn't be too difficult.

I used some adapters from I think the speed shop, a few feet of power steering hose and reusable fittings to make the hoses to adapt the VW power steering pump to my steering box.

I didn't have any abs to worry about,

Is this a hydro boost type system? I've not worked with any Toyotas past 1986.

If you want ac I'd probably at least get the AC compressor fitted up while you're in there. It's a tight fit between the upper control arms. Will prevent downtime in the future to at least make sure it will fit, I had to make a custom bracket and raise the compressor up and inch or two.

 

[MoabPorkChop]

Im planning on having to adapt the PS pump lines and the AC lines. I will be using only the VW accessories. Once it drives I will start worrying about making the rest work. The engine I have has AC so I will fit it with the engine.

The engine mounts are part of the front torsion bar mount. I was planning on cutting them off of the frame and starting from scratch but now I am going to start with attempting to reuse the original mounts and just building mount to engine. I dont want to have solid mounts. I would like some rubber in the middle to isolate all the vibration I can.

This is a rear abs only truck and my abs light has been on for years. I may just delete it.

Matt.

 

[dohcdelsol93]

I wasn't going to suggest openly to delete the abs, but it it was mine it would have dual diaphragm pump, Chevy 1 ton master cylinder and 4 wheel disks. I love my 4 wheel disks although the parking brakes suck. Then again the transfer case drum brake on my 40 also sucked. I don't live in a real hilly area but keep a few plastic wheel chalks in the back just in case.

I kept my frame mounts in place, I built engine side mount brackets to fit the yota frame. Even used the 22re engine mounts. My BHW is balance shaft deleted and I have no undesirable vibrations, keep in mind I also had a 40 daily driver with a 4bd2t swap so my threshold of vibration might be more than others.

I had to make a custom ac mount bracket and tensioner to fit my VW compressor as it hit the upper control arm on the passenger side, however there are many vw accessory set ups, my BHW was set up like a rwd vehicle making it easier than a fwd Jetta ALH

 

[MoabPorkChop]

I put the engine in today...then took it out...and put it in...and took it out...

The only interference is with the turbo intake side and the passenger engine mount and the abs/power steering. These will take some fiddling but are not insurmountable. In the pictures the engine is still a little high and not quite against the transmission but there is room.

 

[MoabPorkChop]

Sorry...there was a duplicate picture of the brake lines.

Here are some more.

 

[dohcdelsol93]

I stood my engine straight up and down (0 degrees) and used the TD conversion specialist clocking adapter to help with that.

The 2 inch body lift and diff drop kit also helped with under hood space. I'm guessing I could have cleared the front diff with just a 1 inch body lift, using just the diff drop I think it would be tight. Possibly doable but I wanted plenty of turbo/hood clearance. These jokers get hot and I didn't want to ruin my new paint.

Im not sure what oil pan you're running, I used the metal/aluminum hybrid pan with matching oil pickup. It's still a tall motor at the crank pulley vs day a small block Chevy but fit much better than the OEM pan.

Have you put any thought into gear ratios?

I'm running approximately 33 inch tires. The factory 4.10 gears were great on the freeway but sucked for traffic light to traffic light acceleration and I was always down shifting while trying to maintain 40-45. It was miserable. (R150f)

Switched to 4.30 gears and its happier everywhere. At 75/80 I'm about 3000 rpms, which is about the fastest I feel safe in this old lifted rig anyway. 3k sounds like a lot but she'll scoot along all day at that rpm and still return 24/25 mpg. Some claim 30mpg plus but 26 is the best I've done. Perhaps the mud terrains, tube bumpers and 4-6 inches of total lift hurt my aerodynamics a bit. A single 10 ply tire weighs about what all 4 Passat tires weighed all together.

 

[MoabPorkChop]

I stood my engine straight up and down (0 degrees) and used the TD conversion specialist clocking adapter to help with that.

Im doing the same. Im using the TD conversion adapter and have it on the most vertical setting. I was expecting a week of fiddling with the placement to get it right but I think I found the direction I'm going to go in just a day. Things are fitting really well so far. I have more clearance behind the vacuum pump/fuel pump that I thought I would. Maybe I have a transmission from a 3.4 with the longer input shaft. I thought I would have to fight the firewall but it looks like Ill have just enough room.

The 2 inch body lift and diff drop kit also helped with under hood space. I'm guessing I could have cleared the front diff with just a 1 inch body lift, using just the diff drop I think it would be tight. Possibly doable but I wanted plenty of turbo/hood clearance. These jokers get hot and I didn't want to ruin my new paint.

Im not sure what lift I have or if I even have one but the diff is in its stock location. I wanted to drop it but the kit I bought only spaced the diff bushings down about an inch and didnt lower the front mount at all only resulting in rotating the diff down a little. I decided not to use it and if I can move the passenger side engine mount back a couple of inches and get rid of some PS lines it should settle down like it was made to be there.

Im not sure what oil pan you're running, I used the metal/aluminum hybrid pan with matching oil pickup. It's still a tall motor at the crank pulley vs day a small block Chevy but fit much better than the OEM pan.

I am using the pan that came with the BEW engine. I have no idea if it was the stock pan but I assume it is. It has a notch that seems like it was made to fit around the differential.

Have you put any thought into gear ratios?

I'm running approximately 33 inch tires. The factory 4.10 gears were great on the freeway but sucked for traffic light to traffic light acceleration and I was always down shifting while trying to maintain 40-45. It was miserable. (R150f)

Switched to 4.30 gears and its happier everywhere. At 75/80 I'm about 3000 rpms, which is about the fastest I feel safe in this old lifted rig anyway. 3k sounds like a lot but she'll scoot along all day at that rpm and still return 24/25 mpg. Some claim 30mpg plus but 26 is the best I've done. Perhaps the mud terrains, tube bumpers and 4-6 inches of total lift hurt my aerodynamics a bit. A single 10 ply tire weighs about what all 4 Passat tires weighed all together.

I am going to leave the gears stock for now. I have 31x10 milestar MTs and the speedometer seems about perfect. I wouldnt mind taller gears for the highway now that I should have the torque to push it at lower rpms. Anything will be better that my slowly fading 3.0. The mileage was dropping and the power with it. I was following semis up hills @35mph fully floored. The 3.0 had 200k on the speedometer and no speedometer cable for at least the last 2 owners.

I have plans to go through the whole drivetrain but I havent decided if I want to go stock or start making changes. One slippery slope at a time. I fallen for the "while Im in there" logic enough to be cautious.

Matt

 

[dohcdelsol93]

If I'm not mistaken the 3.4 input shaft is about 11 inches long vs about 9 for the 3.0.

 

[MoabPorkChop]

If I'm not mistaken the 3.4 input shaft is about 11 inches long vs about 9 for the 3.0.

i was thinking that that might be why I have the extra room by the firewall. I have a 3.0 transmission Im going to put in and I can compare them. My next objective is to pull the engine again and remove the parts that are interfering and try again. Once I get the engine mounted I will swap out the transmission and then start building and connecting all the accessories.

Im working this weekend so more progress will come next week.

Matt

 

[dohcdelsol93]

If you switch over to the BRM intake manifold with race pipe it sits slightly lower (also believe it flows almost as well as a pd150 intake) and you'll lose the hunk of metal where your EGR formerly attached.

 

[MoabPorkChop]

If you switch over to the BRM intake manifold with race pipe it sits slightly lower (also believe it flows almost as well as a pd150 intake) and you'll lose the hunk of metal where your EGR formerly attached.

I think I can lower it down enough to clear the hood. Also, I was wrong in my earlier post…the vacuum pot for the turbo was hitting the mount and the cold side outlet was hitting the abs pump.

 

[dohcdelsol93]

Are you taking about the wastegate? Metal, has a port for a vacuum hose on the top center and a threaded rod on the bottom side that controls the veins of the turbo?

The vacuum pot or vacuum canister is usually mounted on a fender well or part of the body and is plastic.

Some VW cars don't have a vacuum canister however even if I didn't have one I'd add one. It's nice having one last power assist pump on the brakes should the engine ever die in you while operating.

Going back to VW parts being interchangeable, a BHW exhaust manifold and turbo is a performance upgrade and gets the turbo higher up. This means a little more space at the control arm/engine mount plus extra starter clearance.

The BHW coming from a 04/05 Passat diesel