My S2 coupe bit of a rebuild and repair thread.

[B5NUT]

Thanks Dave, the system has been flushed a couple of times since I got the car. Where is the filter is it near item number 7
filter.jpg
Also has anyone got a spare hose for sale (number 8) looks like mine could have a very small weep just near the pump.

[Rikki Kitto]

Ill try find it for ya bud

[Tractor Dave]

Can't remember now. Down there somewhere

[B5NUT]

Found the filter, it's part of the banjo bolt, and it was a good call Dave and it had a fair amount of dirt in it.
Screenshot 2023-07-03 191819.jpg

All washed out with brake cleaner.
filter.jpg

Fitted the refurbished bomb a few weeks ago, and thankfully the bomb light has not come back on. The fluid in the PAS reservoir does rise when the engine is switched off, but when started it only drops to the level it was filled to (next the maximum line) where as before it would rise to the top with the engine switched off but drop below the minimum line when the engine is first started only to rise above the line a few second later!

Have to say Pleiades Garage did an excellent job on the refurbishment looked band new when they sent it back.
bomb.jpg

Next up was to look at the diff lock indicator. I figured all of the bulbs had failed as both of the illumination bulbs did not work and the activation light did not work. I replaced the illumination flat top bulbs with grain of wheat bulb as much as I tried I could not find any of the flat top bulbs. Anyone know where you can buy these from?

1-bulb.jpg

Decided to bench test the light and to my surprise the diff indicator bulb did light up. So I had other faults with the diff locking setup.

After testing the vac line going to the control unit I tested the control unit and it switches the vacuum between the two pipes I looked at the new actuator I had fitted and sure enough it was dead. This was a new Mercedes unit that I picked up at the dealership! I know it was working when I picked it up, so in less than 2 years and 0 usage it's dead. Unfortunately the unit was modified so I cannot return it and did not what to spend another £50/£60 replacing it. So I dug out the original Audi unit off the car.

The down side to using this is I've had to mount the actuator upside down as the original mounting holes were damaged due to rust expanding the screw holes and cracking the plastic.

2-actuator.jpg

While I was there I also replaced the rubber boot as I did find a cut in the boot that was well hidden, so it was replaced with a spare I had.

So with that fixed the diff activation light was still not working, and I also read the ABS light should come on the dash which also did not activate when the switch was pressed. So the next test was the switch fitted to the back of the diff, and sure enough this was also dead. After cutting it open I found the internal seal had failed and it was full of oil and some dirt The contacts were also well tarnished and no longer made a good clean connection. So, surprise surprise the switch is now EoL and has been for many years, I asked around but could not find a replacement one. So looked around for another solution and the only one I could find is this switch. It's a reverse light switch used in older Audi gearboxes and it's still available.
3-switch.jpg

Next was to sort out the wiring, as the connectors are different and I didn't want to cut up the cars wiring harness I made an adapter using parts of the old switch. It's not the neatest solution at the moment, but will do until I can figure something better out.

4-adapter.jpg
5-harness.jpg

So with that all fitted I now have a fully working diff lock system (Not that I will ever use it), which started out with what I thought was just a failed bulb. Also thanks to Dave for help with fault finding and some knowledge on the rear differential as this is the first time I've delt with a system like this before.
6-working.jpg

Don't think I will ever need the system, but I hate faults on the car so had to get to working again. For the moment all of the electrical & mechanical systems are now working on the car. Still have a fair few tidy up jobs to do but it's a couple more jobs off the list.

[Tractor Dave]

Nice work.
Handy to know about the switch replacement.

[B5NUT]

Thanks. I'm still wondering why the merc actuator failed. From what I can see the control unit provides a slight pressure down the pipe with the blue stripe, I guess that is to keep the actuator arm in. Now I'm guessing the Merc does not apply the pressure all the time to the unit, so has that caused the early failure? Anyone else running the Merc actuator and knows there's is still working?

[Tractor Dave]

I pulled one apart to see what makes them tick. It's a simple rubber diaphragm between two halves with the actuator rod connected in the centre. Both the Audi and Merc unit are identical and made by the same company. Only the mounting holes are slightly different and obviously the rod end.

[B5NUT]

Well as I had nothing to lose with the actuator I just opened it up by prising it apart with a couple of flat blade screwdrivers and found the fault! looks like it was not assembled correctly

Diaphragm was not fitted correctly and is bent like a banana on one side.
seal.jpg

Straightened that out and put it back together and it's now working again Will keep it as another spare in case the Audi one fails at some point.

[B5NUT]

Been away for the forum for a couple of months, just talking a break really. Was finding I was spending far too much time on all the Audi forums I was a member of, so have unsubscribed from a few. Also sold the TT a week ago! My wife changed jobs and now walks to work so having three car on the drive going nowhere each day just made no sense. So the TT had to go, It will be missed as it was cracking car and would have another one again.

As for the S2 it's running well, however due to the weather this year it's not had much use. Took it to Scotland for a few days on a family holiday which was nice and it never missed a beat. Been a cheap year for the S2 so far, £100 on the brake BOM and a few quid on bulbs, seals and service parts so around the £200 mark.

Other job this year was the door cars. The leatherette had stated to come away and the foam started to fall out over the arm rests. I purchased to 2mm scrim foam from local trimmers and set about the job. First job was dismantling the door card. Worst job was the door pocket, the melted posts that hold the pocket on were all over the place (must have been a Friday afternoon special at the factory) and were a sod to grind away. The metal clips were not too bad to get off. Found a tool that was able to get in behind the clips and remove them in one piece.
1-clip.jpg

Removing the old glue was the awful job, from what I have read some members were able to peal the old glue away however on my car after scraping the old foam away the only way of removing the old glue was thinners.
card1.jpg

After a few minutes with thinners.
2-card.jpg

The leatherette after scraping and cleaning the glue off. Also need to see how that moisture is getting in to the lower section.
3-card.jpg

It was at this point it all went to hell. I was able to glue the foam to the leatherette Ok using contact spray adhesive, however when trying to glue the foam/leatherette back to the door car it all went so badly, the contact adhesive just gripped to quickly and no mater how hard I tried I just could not get it aligned without a section grabbing to the door card and starting to rip the foam as the glue was setting.

So I gave up and had a think for a few days. I had a think about how people were able to peal their glue off so had a look at double sided tape options, and I came across this 3M product 3M GPT -020F Clear Double Sided Plastic Tape, and it comes in nice wide 100mm strips.
5-card.jpg

This made alignment far easier as you can get it all aligned then peal the backing back one strip at a time.
4-card.jpg

I forgot to take some picture of the final finish but it looks a 100% better than the leatherette pealing away from the cards. Job for next year will be replacing the headlining as it's coming away around the passenger sun visor, but it's only noticeable when the sun visor is down.

[Fat Audi 80]

Been away for the forum for a couple of months, just talking a break really. Was finding I was spending far too much time on all the Audi forums I was a member of, so have unsubscribed from a few. Also sold the TT a week ago! My wife changed jobs and now walks to work so having three car on the drive going nowhere each day just made no sense. So the TT had to go, It will be missed as it was cracking car and would have another one again.

As for the S2 it's running well, however due to the weather this year it's not had much use. Took it to Scotland for a few days on a family holiday which was nice and it never missed a beat. Been a cheap year for the S2 so far, £100 on the brake BOM and a few quid on bulbs, seals and service parts so around the £200 mark.

Other job this year was the door cars. The leatherette had stated to come away and the foam started to fall out over the arm rests. I purchased to 2mm scrim foam from local trimmers and set about the job. First job was dismantling the door card. Worst job was the door pocket, the melted posts that hold the pocket on were all over the place (must have been a Friday afternoon special at the factory) and were a sod to grind away. The metal clips were not too bad to get off. Found a tool that was able to get in behind the clips and remove them in one piece.
1-clip.jpg

Removing the old glue was the awful job, from what I have read some members were able to peal the old glue away however on my car after scraping the old foam away the only way of removing the old glue was thinners.
card1.jpg

After a few minutes with thinners.
2-card.jpg

The leatherette after scraping and cleaning the glue off. Also need to see how that moisture is getting in to the lower section.
3-card.jpg

It was at this point it all went to hell. I was able to glue the foam to the leatherette Ok using contact spray adhesive, however when trying to glue the foam/leatherette back to the door car it all went so badly, the contact adhesive just gripped to quickly and no mater how hard I tried I just could not get it aligned without a section grabbing to the door card and starting to rip the foam as the glue was setting.

So I gave up and had a think for a few days. I had a think about how people were able to peal their glue off so had a look at double sided tape options, and I came across this 3M product 3M GPT -020F Clear Double Sided Plastic Tape, and it comes in nice wide 100mm strips.
5-card.jpg

This made alignment far easier as you can get it all aligned then peal the backing back one strip at a time.
4-card.jpg

I forgot to take some picture of the final finish but it looks a 100% better than the leatherette pealing away from the cards. Job for next year will be replacing the headlining as it's coming away around the passenger sun visor, but it's only noticeable when the sun visor is down.

Thanks for this. I have already completed this job on my drivers door using contact adhesive and it worked pretty well. Good to know there is "tape" alternative...

[B5NUT]

I really struggled, once the adhesive started to go off and grab every time it touched the door card it just ripped the foam. Having part of the armrest in the way made it a lot worse, if that was not there it could have been easier.

[s2driveruk]

That is a good find, how much was a roll of tape?

[B5NUT]

For the role from RS is was £70 so not cheap, however there are suppliers that sell it in smaller rolls. I've got a fair amount left if anyone want to buy some.

[K Simmonds]

That 3M tape is a really good find, should make the job much easier. I'll see if I can get a half roll at trade price as it's expensive but being able to do it in stages is much more sensible then trying to get it on in one hit. The ones on the front doors of my RS2 are going to need doing and I'll use this method, save's getting in flap with spray adhesive.

I hate recovering door cards, the old foam and glue is always a pain to remove, we use panel wipe at work, not quite as aggresive as thinners but it does the job.

[B5NUT]

I you need some of this stuff let me know, I still have plenty left.