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Looking for a hand with Turbo MPFI Engine Electrical System


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I just picked up a 1974 Super Beetle w/ an EA82T. The engine was pulled from a 1987 GL-10. It's a half completed project and I get to finish it up. It has set for a few years, so I'd like to fire up the engine for a quick test. What is the bare minimum wiring I can get away with hooking up to perform this test.

 

I'm looking for a high quality scan of the engine electrical system. Something like this, but higher quality.

 

post-57858-0-12583000-1428726067_thumb.jpg

 

I should probably mention, I am a noob. This is my first car project. Nothing like jumping in with two feet, right? :) I do have quite a bit of electrical, electronic, and audio repair knowledge. I can read schematics and follow instructions. Basically, with the help of the internet, I can get through just about anything.

Edited by Snerp
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is anything wired up ? Fuel plumbed ? Got an ECU with a part number to help others zero in on this for you. The distributors part number may be a help as well.

 

Currently the harness is in a box, half hooked together. I want to get a pinout on the individual ECU wires so I know what they are and how long they need to be. Then I will measure each one, and mock up the harness on a piece of plywood w/ nails.

 

Fuel is half ran and so is cooling. Currently the lines are metal, but I would like to replace it.

 

 

This was exactly the extreme break down I was looking for. TYVM! I assume 87 and 89 are the same engine system?

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For a noob, can I suggest a different path? I learnt this from being a noob myself.

It will take a lot more time, but is less prone to having something go wrong.

 

If you have a complete car loom, I'd suggest actually getting the loom laid out, plug in the loom, hook up a fuel supply, radiator, etc, and get the engine running with the loom not in the car.

Be careful to get the earth wires all hooked up back to the car.

 

This will get your engine working.

 

After that, I'd suggest tracing the wires from any plugs in the loom that aren't connected, because if the engine works without them plugged on, the wires are also redundant.

But only do 1 wire at a time. And cut it first only before removing it. Retest the engine works after each wire is cut, otherwise you'll never know which wire to fix after you've removed one too many (I've ended up buying a whole car for the working loom before to fix this problem, $300 I'd like to have back in my pocket :( )

And if you find that the engine still works, then remove that wire, otherwise you can simply solder it back together.

BTW, be careful of the wires that come from both the coil signal to the ECU & exhaust oxygen sensor, they are both shielded back to the ECU, so can't simply cut them anywhere along their length & rejoin.

 

I'd also recommend not using measurements of the length to work out how long the wires should be. There's always something in the way when you run a wiring loom.

Lay the loom in the car, tie it to everything you what to secure it, mount the ECU, then with the loom in position, start to cut & resolder each wire in position.

Guaranteed never to go wrong. And don't forget to leave some slack for maneuvering loom for undoing plugs, etc.

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Not neccisarily. What does the MAF sensor look like? Is it a flapper door or a hot wire?

 

I'll have to take a look. I have Tuesday off and plan on spending some time on the car.

 

For a noob, can I suggest a different path? I learnt this from being a noob myself.

It will take a lot more time, but is less prone to having something go wrong.

 

If you have a complete car loom, I'd suggest actually getting the loom laid out, plug in the loom, hook up a fuel supply, radiator, etc, and get the engine running with the loom not in the car.

Be careful to get the earth wires all hooked up back to the car.

 

This will get your engine working.

 

After that, I'd suggest tracing the wires from any plugs in the loom that aren't connected, because if the engine works without them plugged on, the wires are also redundant.

But only do 1 wire at a time. And cut it first only before removing it. Retest the engine works after each wire is cut, otherwise you'll never know which wire to fix after you've removed one too many (I've ended up buying a whole car for the working loom before to fix this problem, $300 I'd like to have back in my pocket :( )

And if you find that the engine still works, then remove that wire, otherwise you can simply solder it back together.

BTW, be careful of the wires that come from both the coil signal to the ECU & exhaust oxygen sensor, they are both shielded back to the ECU, so can't simply cut them anywhere along their length & rejoin.

 

I'd also recommend not using measurements of the length to work out how long the wires should be. There's always something in the way when you run a wiring loom.

Lay the loom in the car, tie it to everything you what to secure it, mount the ECU, then with the loom in position, start to cut & resolder each wire in position.

Guaranteed never to go wrong. And don't forget to leave some slack for maneuvering loom for undoing plugs, etc.

 

The harness I have has already been trimmed down by the previous owner. Worst case, I could completely rebuild it...as long as I get the proper wiring diagram. :) I was really hoping someone could just tell me what I can and can't remove though.

 

If the coil and O2 sensor wires are cut, couldn't I just replace with shielded wire? I'd really like to avoid having to buy a whole new harness just over some shielded wires.

 

When I say measure, I mean using string for the run, measuring the string and then making my cut. I saw somewhere someone doing that when dropping an EJ22 in a bug.

Edited by Snerp
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I'm not seeing any markings on the Distributor. The MAF is on the top of the air filter housing, correct? I believe that's what I was told. Here's pics of the MAF and ECU

 

MAF:

 

29bgd8h.jpg

 

ECU:

 

28sn4lf.jpg

Edited by Snerp
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That is an 86 turbo ECU and associated flapper MAF.

You need a different diagram from the 89 hotwire MAF system.

 

What years would work for me? Does that mean the donor car was actually an 86 GL-10?

Edited by Snerp
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Ok, I tracked down the full 1986 factory service manual. Got it for $62.50 shipped. Not too shabby considering some sites want $120 + s&h. I searched for separate sections and pieced together the whole manual from different sellers.

 

I will scan in the wiring diagram for anyone who may need it in the future. Thanks for all the help! :)

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OK, some good info is in the factory manuals.

 

Your dizzy must be a bit grubby then, not to see any markings. Not a plate attached, rather numbers impressed in casting on the outside of the body. Should also have  vac can on side, and four pin module inside.

 

This works in conjunction with a separate KCM - knock control module and knock sensor. I have run mine with KCM disconnected, so that won't stop you from test running engine. Need to also check the coil is compatable or even correct part number.

 

The 85,86 is identified by the flapper AFM and I guess the ECU part has been identified as well. Good luck

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OK, some good info is in the factory manuals.

 

Your dizzy must be a bit grubby then, not to see any markings. Not a plate attached, rather numbers impressed in casting on the outside of the body. Should also have  vac can on side, and four pin module inside.

 

This works in conjunction with a separate KCM - knock control module and knock sensor. I have run mine with KCM disconnected, so that won't stop you from test running engine. Need to also check the coil is compatable or even correct part number.

 

The 85,86 is identified by the flapper AFM and I guess the ECU part has been identified as well. Good luck

 

Yeah, Dist was a little grubby. All these parts I have came out of the same running car or so I was told. No reason not to believe the guy. He was pretty up front about everything. I think he just maybe got the year wrong. 86 instead of 87. It would explain why he was having trouble with the wiring.

 

The coil has this: E12-116 12V

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i had a made in 85 for the 86 MY , sold as an 87 EA82T which confused some parts ordering until things were resolved with its VIN BROBE letters think they were - you may need to borrow a VIN from someone with exact same bits if ordering from genuine.

 

Is there another single number or letter label stuck on the dizzy. Am not too sure on those number compared to mine

 

We want some pics mate !

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i had a made in 85 for the 86 MY , sold as an 87 EA82T which confused some parts ordering until things were resolved with its VIN BROBE letters think they were - you may need to borrow a VIN from someone with exact same bits if ordering from genuine.

 

Is there another single number or letter label stuck on the dizzy. Am not too sure on those number compared to mine

 

We want some pics mate !

 

Those numbers were on the coil. There is a big white "H" on it as well. I'll hook up some pics tomorrow probably. I'm running out the door to work.

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the H is likely what others can relay back easier - I think the large letter was to ensure correct coil went in on assembly by using one letter rather than a long part number printed in green ? on a shiny blackground of the coil body.. I'll check my coil when I can get at it

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1zdrcwh.jpg

 

157hrvd.jpg

 

21c9vue.jpg

 

Pics of the ride, engine, and a pic of the dist. I still can't find anything on the dist itself. There is a brass piece that is hanging off of it in the back of that pic, it reads 5615. Don't have time to look that part up so I can sound smart...heading in to work again lol.

 

Also, quick question: The cooling system should be Alu, correct? The previous owner was planning on running copper. I want to stick with one or the other, for obvious reasons.

Edited by Snerp
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hmmm, looks OK in the back there - much more contained than an EJ20 turbo I have seen jammed into the back of a similar vintage Bug :)

 

OK. Heater cores are copper and think factory radiators always been plastic tanks with aluminium cores. EA81s had copper radiators.

 

The brass tag may just be a wrecker part tag ?

I think the part numbers, two lines of numbers, will be about behind where the black cable tie is on heater hoses.

Hey, a water heater core conversion coming up !!

 

Keep an eye out for the knock sensor which is just behind and below the S of SUBARU in the cast inlet turbo pipe. Should be white plastic and two pins inside, plugs couple up with dist wiring and off to the knock sensor module. The original loom had near coil, a black wire, white trace, and whte single plastic female terminal inside to monitor knock sensor. Your beast may be so lightweight - 650kg ? may not even feel a knock unless you load it up with fat chicks :)

 

Right now, I bet you would love an app that you could download to run that baby from a phone or ipad!

 

Those injectors are batch fire, or mine were...1 3  squirt together, 2 and 4 paired off with each other also.

I have switched the wiring and had no change in idle or free revving only.

 

You are gonna have to youtube the first start for us :)

Edited by jono
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I got started on the wiring a bit yesterday and did a little today. I was trying to salvage what was already done by the previous owner, but I think I will go ahead and pull apart all of the systems and start over. He was working off the wrong diagram and that became apparent. No disrespect to him though...This was a tricky one to figure out.

 

So it looks like I have the wiring for fuel injectors, air intake, ignition, turbo/vac, and temp sensors. Am I missing anything?

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throttle position switch - it will likely be the switch type rather than th position sensor type.Think it is three wires. One switch indicates closed throttle, next one indicates about 2/3s open.

 

I like to think a second earth between ECU and engine block is a good idea. They had an earth point between TB and dizzy, closer to TB on a thread post/boss using M6 bolt

 

ECU temp sensor - CTS is in the rear bolt on section of the inlet manifold and not tyhe gauge sender in the thermo housing ...

Edited by jono
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Ok, I've still got a rat's nest of wires, but I have almost everything hooked up. I just want to make sure this engine is running and then I'll make it pretty. I have the fuel pump, coil, battery and ignition left to go. Then I'll finish fuel and cooling lines and try to fire her up.

 

I thought I was missing the knock controller unit. After a tantrum I remembered another box of wiring and there she was. Pretty funny.

 

The coil wiring seems a little off, I'm wondering if it isn't a coil off another car...I believe I saw two around here somewhere. I need to take another look tomorrow.

 

Also, where does the boost and vacuum switch tie in? I'm having a little bit of a tough time with that as well. Not really seeing where the line goes in my diagrams. I'll keep searching the manual though.

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What's the coil look like? The Subaru ones have only 2 screw pins.

Positive power with ignition on & negative which provides tacho signal & signal to ECU.

Don't forget to connect this negative coil wire to the ECU signal. It will not run without it. I had a project crank but not start through 6 months of troubleshooting because I didn't have it connected :(

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