I'm Bored… but I have an '89 Audi Coupe Quattro 20V and a factory manual

[Rikki Kitto]

I used the flat end of a crow bar

[Rikki Kitto]

https://www.raptorsupplies.co.uk/pd/...iABEgIUavD_BwE

[Greg_S]

For your brake accumulator I have just had mine refurbished by Pileades which I know has done quite a few on the forum. Worked out just over £100 including shipping back to me.

[predding]

At this point I don’t even know anymore...

I threw in a pic of the thermostat for reference.
:

I have been following the coolant overtemp issue as I have same overheating on my RR 20v. Is this mark on the tsat just a Mahle thing or should I be looking for it on the Febi one I have. My digital temp gauge goes right up and and down despite having cleaned and flushed like you have done. I am replacing all three temp sensors (two under the coolant manifold and the one at the rear of the head) to eliminate any gremlins there. And the Lambda sensor as its still misfiring under load and running rich at the exhaust. Can I borrow you 'head hitting a brick wall' emoji as I am sick and tired of this damn car and TBH if someone rocked up with 70k Euros, they can have it...

[pscouto]

Hello everyone,

I’m back working on the Coupe again, and this time with a "while im in there" mission in mind. Work kept me away from the garage (and the oil stains on my trousers that my wife definitely loves ?), but now I’m back at it.

I was able to daily drive the car for a while, and honestly, the difference compared to before is huge. The engine response is much better and very satisfying. It’s not a fast car by modern standards, but it’s a really fun package. Overall performance has improved a lot… although it’s still far from perfect.

I also want to share my work with you guys and get your critical input, even knowing that I’ve probably already made a few mistakes along the way. That’s part of the process.

I refurbished my garage and picked up some tools and equipment based on my previous experience, basically all the things that made life difficult last time because I didn’t have the right gear. Now I feel much more comfortable tackling these jobs.

So, I’ve started putting together a list of things to address—some annoying, some urgent, most just age-related.

Engine temperature
One of the most frustrating issues has been the temperature gauge going above spec. I’ve read a lot about possible false readings from the sensor, but the car genuinely felt hot, and it was always in the back of my mind while driving. There were no clear signs of overheating, but still—it didn’t feel right.

What I’ve done:
I ordered a kit from 5inline with a water pump (correct tooth count), a new temperature sensor, and new belts. Hopefully, this will sort the issue.

Heating system overhaul
I removed the dashboard and replaced the heater core. The system was only blowing cold air and was full of brown foam debris—so the internal flaps were clearly gone.

I also removed the heater core because I wanted to properly clean the entire cooling system. Last time I replaced the radiator, but I didn’t replace the hoses or the heater core. What ended up happening was that the expansion tank started showing a lot of rust contamination. So now I’ve decided to go all in and refresh everything—hoses, radiator, auxiliary radiator, heater core, expansion tank—basically the entire cooling system.

The idea is to eliminate any old or contaminated parts from the equation. When I install the new water pump, I want everything to be new and properly flushed, with no rust or debris left anywhere in the system.

While I was in there, I:

• Removed the AC unit
• Installed a non-AC vent tunnel and blower motor
• Added the bracket for a pollen filter

The resistor pack was different from what I had, but with a few tweaks, I now have all fan speeds working again.

For the flap material, I replaced the original foam with aluminium tape. It’s heat-resistant and lightweight, so I’m hoping it will be a durable solution. Time will tell.

Fuel smell / running condition
Another issue that has always bothered me is a strong fuel smell. I suspect the AFR is off. It looks like someone before me messed with the throttle settings and CO levels.

Also, my engine breather hose was the soft type and completely collapsed. I’ve now bought the rigid version with the proper adapters from Audi Tradition, and I’m planning to install a catch can in between as well.

I removed the spark plugs and found black tips and oily threads. The black tips make sense if the car is running rich, but the oily threads made me check further. I opened the valve cover to see if the gasket was compromised (possibly something I did wrong during the last install), but everything looks clean.

So at this point, I think it’s a combination of factors rather than a single issue.

Hydraulic system (brake pressure accumulator / power steering)
Another thing that was making a mess in the car was a leak from the brake pressure accumulator and the power steering pump.

This was a costly mistake on my part. Last time, I only replaced the pump and didn’t do anything about the pressure accumulator. The pump kept whining, so I started reading more about it and it seems the “bomb” had lost pressure and ended up compromising the whole system.

This time, I decided to do it properly. I bought a refurbished pressure accumulator and a pump from Autewo.de, so I can replace everything together. Let’s see if this finally fixes the issue.

General work & other findings
I also took the time to review the sound system—installed new speakers and kept only the original tweeters that were still working well. I replaced the old wiring, tested everything, and the improvement is great. It’s a low-budget setup, but more than enough for me.

I also replaced the dashboard buttons, as the old ones were burned out (still not sure why that happened).

While I was working in the boot area, I took the opportunity to check the fuel tank and clean everything. I’m really glad I did—the rubber gasket was completely gone. That could also explain part of the fuel smell inside the cabin.

So now I’m going even deeper: I’ll replace all rubber hoses… classic “while I’m in there” situation.

At this point, the scope of the job is getting big. The “while I’m in there” theory is starting to make a lot of sense… now I understand "money pit" ?

Just to say, I'm an amateur, learning as I go. That’s honestly the part I enjoy the most. So this is all a bit of trial and error… let’s see what works!

Water leaks & interior restoration
This was a big one. I had water getting into the car from multiple places. On rainy days, the driver’s floor mat was always wet, and I also found moisture in the boot and even the headlining.

We had a lot of rain here in Portugal this year, and on two occasions the Coupe was left outside—it was a complete mess! But at least it confirmed this has likely been happening for a long time.

I started digging under the carpet and found the insulation completely soaked and deteriorated… so I made the obvious decision:

Remove everything! ? (cue nervous laughter)

I removed the seats and the carpet, and the insulation underneath was basically creating its own ecosystem… definitely time to cut everything out. Mask on, proper cleaning, and dealing with mold.

Luckily, we had around 25ºC here in April, so I could take advantage of direct sunlight to dry everything properly.

I cleaned the carpet using a carpet cleaning machine, which worked really well—judging by the color of the water coming out, it definitely did its job! After everything was clean (apart from a few stubborn stains I couldn’t remove), I started applying sound-deadening material.

After that, I installed a new insulation layer with a similar thickness to the original. Put the carpet back in place, and overall it looks good again.

I also removed the headliner. I bought a new sunroof rubber gasket, which I still need to replace—and I have a feeling it’s going to be a bit of a pain.

After removing the headliner, I found rust around the water drainage pipes. I believe these are the sunroof drain channels, and they were probably clogged, which caused them to rust from the inside out. I still need to properly inspect and understand how to fix this.

Some of the plastic trim pieces basically disintegrated due to sun exposure, but I managed to source used replacements on eBay.

Right now, I’m waiting for more sound-deadening material so I can treat parts of the roof and start putting everything back together.

While I wait, I’ve moved on to suspension and running gear. I’ve never done brakes before, but with the right tools I managed to tackle it. I bought new discs and pads, Bilstein B6 shocks, gearbox bushings, differential bushings, and a steering damper.

To avoid making the car too harsh, I’m planning to keep most components OEM, except for the wishbone bushings where I’ll go with polyurethane—hopefully improving handling without making the ride too stiff.

At this point, I just want to address everything properly.

I even considered buying a daily driver… but honestly, no. I want to daily the Coupe. In the end, I believe the investment will be worth it.

More updates soon as I continue digging into this.

Cheers!

[pscouto]

And more:

[pscouto]

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[pscouto]

Any help will be greatly appreciated!!

[Tractor Dave]

So you have been busy!
Were those plugs properly torqued? Looks lime they have been blowing by. And yes, you are running a bit rich by the looks of things.
Well done. Looks like you are a quick learner.

[PeterS]

BTW the 7a motor is happier with tri-electrode sparkplugs https://20v.org/plugs.htm