The Project Pad

Stock pump will work just fine.

Greg W/

that tank looks pretty horrid. I'd be tempted to clean the hell out of it or replace it.

Yeah. I'm taking it out today. Joe Marconi has one a few hours north of me but I'm going to try a cleaning first

Grillage wrote:Yeah. I'm taking it out today. Joe Marconi has one a few hours north of me but I'm going to try a cleaning first

and check his before you buy it...

I found a guy here local who can clean gas tanks - has a tank big enough to dip an entire car. He's working on it for me.

In other news, I am making serious headway in figuring out how the wiring for this is going to work.

I have the harness all ready to go and am going to be able to completely replace the 7a harness I believe.

The last thing I'm working on is the connections for the non-engine ECU items - so all the power, the speed sensor and the fuel pump.

I'd like to integrate my new harness (from the ABZ) into the car as seamlessly as possible. In order to do so, I'll continue to use the 7A's fuse box and connections.

Most of this stuff runs through the Fuel Pump relay and I have it mostly figured out but need some help...
Here's the diagram on the side of the relay...

and here's where I've traced everything...


As I understand it, 30 and T are always hot. When 86a is provided a ground path, it creates continuity between 30 and 87/87a. thus creating two pathways for 12v to go from 30 to the fuel pump and the injectors.

My question then becomes what are the functions of 85 and L?
85 is grounded on the relay panel and L goes to the ECU (pin 22) and to the Diagnostic connector.

Since the Signal from the ECU comes from Pin 7 I don't know what the other connection for the ECU is - anyone have an idea?

Here's the page from the bentley...

L is a daig connection, you can ignore it on the vems side. older vag diag connectors use the K/L bus to communicate with various devices in the system. vems doesn't talk KL, so dont worry about it.

85 is probably used for some constant ground function inside the relay. the rest you have correct.

I had the last week off and spent a ton of time tracing down all the wiring in the 7A harness so that I can integrate the ABZ harness into it as cleanly as possible.
Here's how it looks so far...


I decided also that I will not cut up the 7A harness at all. There can't be all that many of these uncut so it will be useful to someone. The junkyard nearby has an 88 90 so I went over there and grabbed a bunch of wiring connectors to make the ends I need rather than cutting them off the 7A harness.

I grabbed these...

and forgot this one (the most important) and had to go back. It is mostly the 12v outputs from the Fuel Pump Relay.


There are only a couple things from the 7A that I need to maintain. Those are...

On the part of the harness that connects to Aux Relay panel black connector #6

Tachometer signal from vems needs to come through pin 6
Signal from the Vehicle Speed sensor to the speedometer goes to pin 7 (and is also Teed off to the VEMS box)
Looks like this:


Then, there is harness B from the underside of the main relay panel - It mostly carries 12v signals from the fuel pump relay to other things...

It has 12v to the starter solenoid on pin 2
12v to reverse light switch on pin 4 (fused by #12)
fuel pump signal from ECU to the fuel pump relay on pin 5
12v to coils on pin 6
12v to injectors and fuel pump on pin 8 (fused by #13)
looks like this:



Then there are the outputs for the ISV and the other outputs from VEMS that need to be fused. To keep it clean, I am using the little fuse bar I got from the '88 90. It holds the fuse for that.

Those feeds come mostly from the "L" outputs under the main fuse board

There are a few other connectors that I can ignore from the 7a but there is one more harness I need to make.

In this pic, the one marked "reverse light" is where the other side of the reverse light switch goes - It needs to be made by me.

However the red switch goes from ECU to the AC system (which I'm deleting), the single pin white goes to a electronic thermo switch that is used when there is not auto-check for the coolant temp, the yellow to the ECU and the tan to the 7 pin harness - I don't need any of these

I have to still make the connectors for the reverse light switch and the VSS and then I'm done.

I removed the Air Conditioning bits from the inside of the HVAC box so I have that good sized hole to run the harness through and will have the box live under there I think.

Here is what I am using for the wiring of the VEMS... I will remove the earlier versions from my earlier posts for the sake of simplicity...

I got the last couple connectors the other day and the harness is now 100% done. I was able to test fit it in the car and everything is the proper length and can get where it needs to go. I'm not sure where the VEMS box will end up living, possibly in the glove box, or possibly in the shelf under the drivers side dash.

I also was able to fix the leak in the passenger's side footwell and now can start the process of putting things back together in there.
First though, with no ABS I wanted to remove that harness - so I went through the wiring diagrams yesterday and figured out what was able to go away.
I discovered a couple weird things. Firstly the 6 pin plug for the diff lock control unit had all the wires cut off of it - right at the plug. Looks like something ripped them off or something. Also, the diff lock indicator has a bent pin on it. So the Diff Lock definitely didn't work on this car before I got it. I hope there's nothing else wrong.

here's the carnage - what's not going back in...


I'm left with this...


Just the hookup to the fuse box, the ABS relay will still be there as it powers the diff lock too.

I removed the whole ABS plug and all it's associated wires but had to open up the blue connector from the aux relay panel (#4 in blue called T10c in the bentley) and omit everything EXCEPT for pins 2,4,5 & 8.

Pin 2 is the black/yellow wire that comes from the ABS relay and goes eventually to the ABS switch (which I didn't want to totally cut power to - this is probably not necessary)
Pin 4 is the two Black/Blue wires that power the Diff lock switch, indicator and control unit
Pin 5 is the Grey/Blue wire that goes from the Diff Lock indicator to the Instrument cluster
Pin 8 is the White/Blue wire that comes from the VSS on the trans - I'm guessing that's how it knows to disengage the diff lock at 20mph or whatever it is.

for the ABS relay I yanked pin 6's wires out of the harness - they went to the ABS box that's gone now.

Looks like 10 lbs or weight savings too!
Nice work, wiring can be tedious.

Definitely. My head hurts just looking at the pics let alone doing the work.

Kudos.

Thanks, after tracing down each and every wire in the ABZ and 7A harnesses, this was a cakewalk. I have never really delved into wiring and couldn't read the diagrams so well when I started but now I feel very comfortable tracing these things down.

Now I need to get a PS hose made, the brakes fixed and I'll start the reinstallation of everything. Hopefully the snow stops soon too - I am doing all this in my driveway!

Slight update...

I have been working on the coupe quite a bit but nothing on the exciting front. I thought I had the leaks all fixed but I do not.

I have a couple leaky points - first in the trunk. I fixed that one saturday by removing the drivers tail light and reinstalling with new butyl tape to seal it all up.

The other spots are on the passenger's side both from the cowl under the windshield and also from the top and bottom of that door.
For the Cowl, I used flashing adhesive strips like this...

and then painted it with red Flex Seal - the shit that they spray on the screen door boat on TV.

that seems to have fixed it other than water dripping directly into the HVAC air intake. It used to also seep in around the joints in the metal.

The last spot I'm dealing with is the passenger's door. I have water dripping from the top of the door - from the A Pillar and also from the bottom.

This is definitely part of it...

I'm totally missing the rear door seals on both doors.
I can only get them from Audi tradition but they no longer ship to the USA. :frustrated:
I am getting new door gaskets for at least the passenger's side also. so I hope to finally have the car dry enough to reinstall the carpet and interior.

In more exciting news, I picked this up from Ebay.de...

Complete with new leather.

I also finally got the Power Steering pump hose figured out. I need to take the pump end from the V8 and the Rack end from the Coupe and lengthen the whole thing a couple inches.
I sent the two all marked up with reference points for length and clocking orientation (so the ends hit the pump and rack right)


Lastly, I got a new car yesterday. Needed a larger vehicle for all the driving I've been doing the last year (and will continue to do) for work. Got rid of the A5 and got this...


It has two turbos!

awesome wiring work. I always respect the DIY wiring projects the most. Its by far my least favorite thing to do... even rebuilding broken connectors makes me pull my own hair out. Bravo! cant wait to see more updates.

A couple recent developments...

I got the gas tank back from the cleaner...



SO much better! I will be reinstalling sometime soon.

Also, I got an order from Audi Tradition that included all new door seals. (I have a couple extra sets if anyone needs some)

Got the door seals on and most of the leaking has stopped but not all!
From a garden hose, I still get this...

Looks like it is coming from behind the A Pillar trim.

All I can think is that it is coming from the windshield seal? Has anyone experienced this?


I also finally got the power steering hoses figured out. I sent two hoses out to the Spokane House of Hose as shown above. Unfortunately, I screwed it up and had them put the wrong banjo fitting on the Pump side. I sent it back to them and they put the proper banjo fitting on it for me for no charge. They did a great job. Now I just need to kick the guy making the engine mounts in the ass to get them finally done. It hasn't been holding me back until right now so I've been letting it go.

Only thing I can think of is the windshield seal for that leak.

How would one fix that, just remove and reinstall with a new seal?

Grillage wrote:How would one fix that, just remove and reinstall with a new seal?

Pretty hard to remove a windshield without breaking it. Might try adding some extra sealant in the gaps on the outside or maybe along the inside under the a-pillar trim.

I found where the water is getting in:



There is a split in the metal where the seams are and it drips down from there. With the A pillar trim in, it just runs down and ends up in the footwell

I got the sunroof open and have eliminated the drains there as the culprit. I'll spend some more time tomorrow with the hose trying to fix. Anyone seen this before?

Carlisle has given me a kick in the ass to get this done.

I got the gas tank back in place today and am working next on the battery relocation.

Those who have done this, where do you ground the battery back there?

One of the bolts holding the gas tank cover down.

Ended up cutting up the foam piece that goes behind the gas tank and using one of the rear bumper connections for the grounding point (after a little grinding to expose the metal)



Also, finally wrapped up the gas tank reinstallation. Had to replace a few of the nylon lines as I broke some not knowing what I was doing when I removed the tank the first time. Put in a new fuel pump and filter

While I was at it, it occurred to me that there was likely some nasty gas in the lines theselves so I blew them out...

That gas was NASTY!


Nice to put stuff back together for a change!

yep, was about to mention thats what we generally do, we go to one of the nuts on the rear bumper support crash bars.

if you need to stain your deck that looks like some good stuff to start with right there. ick.

Love it, always worthwhile to click through for a read.

I will have to keep your central spot in mind for my (eventual) battery relocation. I'm just having a tough time figuring out how I want to balance cargo/stereo/spare tire space and the inclusion of a battery doesn't help anything lol

Marc wrote:yep, was about to mention thats what we generally do, we go to one of the nuts on the rear bumper support crash bars.

if you need to stain your deck that looks like some good stuff to start with right there. ick.

Ironically, I do need to stain my new deck!

MY MOTOR MOUNTS ARE FINALLY DONE!

And in time for the weekend too! I'll post pics later today