spartacus 68

What’s the fault, what are the symptoms, is this an in-dash error. I take it you haven’t had the car scanned for fault codes? Manual or auto? The electronic parking brake is normally pretty robust. Rear calipers are known to seize, especially at this age, but you’ve already swapped it out. Are you getting 12v to the module? A cheap multi-meter is invaluable. Also check wiring there, especially the ABS wiring.

Coolant leaks rarely get better. I understand it's a lot of money, but you you run a risk on say a longer journey where the car is to temperature, or even dumps coolant and leaves you stranded. Couple of options, park it up until you have the necessary funds and use for short run journeys. Not sure what you have transport wise near you for commuting, but suspect it's a damn sight better than north of the wall!

The sensors come in a matt black plastic. I actually thing that sensor is painted. I could be wrong, but there looks like a corrosion on the surface. Check with Audi, I think it’s called platinum gray and finished in satin matt. Removing the wheel arch isn’t too big a deal. You need to twist the old sensor out and unhook the wiring anyway, so even tight access isn’t likely to work.

When replacing injectors (use a little ceramic grease on the body of the injector) and check if ‘o’ ring if one fitted needs replaced, plus the seating or sealing washer is new, use new stretch bolts and torque to specification, then tighten union nuts to fuel rail. If a new injector it needs coded to the car.

2017 car could be anything, and sounds suspension related.

Front wheel arch liner needs to come off (usually Torx head screws), and depending on location, engine tray too. Parts made by Valeo. Good opportunity to clean out annyway. Easy enough to prep yourself as Audi will charge small fortune for colour coded one. Make a mask template with card, lightly key PDC sensor with 1500 grit sandpaper, wipe sensor with isopropyl alcohol. First coat of plastic primer, couple of top colour coats and followed by a couple of clear lacquer flash coats. Read you can cure paint by popping in oven for a few minutes (without the rubber ‘o’ ring, but think I’d miss that part out, and just don’t jet-wash directly for a few weeks.

Your local Audi dealer knows how to charge, I’ll say that. Some of those prices are frankly ridiculous. Most of it is wear and tear. The thing to remember is the S4 is a performance car and owning one will come with increased costs. There will be a reason the previous owner had a year, and to coin a phrase ‘wants to get out of Dodge!’ Go into it with your eyes open, or increase your budget and look for something a little younger with full service history. A trusted independent garage that are VAG knowledgeable should be able to reduce some of those costs on labour.

They look genuine, thought I saw the Audi rings near the wheel bolts, turn them over, usually a part number on the rear.

Absolutely the right call. Didn’t want to be all doom and gloom, but a dedicated wheel refurbisher will remove the tyre. Sounds basic, but given any corrosion on the alloy face could be on the rim too, then it all kind of makes sense. In addition, whether 1k or 2k paint, it’s impractical to paint an entire rim with aerosols. There are a few tools out there regards aerosols and trigger sprays, but between masking, weather (wind or flies and other debris), it takes what should be straight forward on paper and turns it into a nightmare. You’ve already said you’re a perfectionist. On the positive, if they are genuine Audi alloys, then that’s half the battle.

Pulling the injectors could potentially be down the road if the problem persists, but I think if I was going to do that - then I'd have them measured with VCDS first to see measuring blocks if there's anything amiss. Pulling injectors is never straight-forward, plus you'll need to seat them with new washers and new stretch bolts torqued to specification. There might even be 'o' rings on the body of the injector. In addition, a new injector if that was the case needs to be coded to the car. Also check vacuum hoses for splits. If it's inconsistent, my advice would always be try cheap route first. Forte diesel conditioner straight into your fuel tank when the fuel light is on and drive it like you stole it. Top up with premium diesel and replace the fuel filter as a matter of course. There's not much I'd put in my car additive wise, but Forte is quality. Used to use it on an old A4 quattro V6 around about MOT time to bring down emissions. Good video here on cleaning and reseating injectors on a 4-cylinder from Dave Sterl.

The biTDI engine is a nice bit of kit. As a matter of course you need to run diagnostics using VCDS and see what's happening. Is it a temperature sensor, fuel-related, or mechanical? If there are any existing DTC errors - then they'll show up on the scan. One thing I would check is the fuel-filter. Should be done every 20k miles. Lives under the driver's side on right-hand drive cars and is straight forward to replace. You can use VCDS to prime after changing. MANN or genuine OE if you're changing it. Check the history to see it's been done. That's a Tiptronic 8-speed gearbox and practically bullet-proof. If it was serviced, was it done using genuine ZF oil and filter? Audi say sealed for life, but should be done by 8 years or 75k miles. Cheaper than a new gearbox as you say. Any performance MAPs or running genuine ECU that you know?

Read this from 2022. Crasher (aka Steve Cresswell) is an administrator for the Volkwagen forum and the VW Audi Forum. He's a highly experienced and skilled mechanic with over 40 years service on VAG cars, and suggests to leave the EGR and swirl flaps well alone. https://www.volkswagenforum.co.uk/threads/proboost-remap-does-it-solve-fsi-engine-woes.41306/ The whole thing is a bit handbags at dawn in my opinion regards being removed from A2OC forum. I'm sure there's more to this than meets the eye!

Refurburbishing alloys is a thankless task, and to be honest it’s one of these things best left to the professionals and powder coating, rebalance, etc. That’s different if it was just a scuff, but this is a full strip-down. The time, cost of materials, including zinc etch primer, base coat primer, colour coat and a few coats of lacquer soon mounts up. If you’re determined to do it, then the alloys need to be spotless. Paint wise, then Würth silver metallic is as close to Audi OE as you’ll get.

Pretty sure it’s chain, not cam belt, and quick scan of that Audi package, does not include brake fluid changes, that would be extra.

If it gives you peace of mind for 2 years, then that’s all that matters. Expensive for what it is, but that’s how these things work.

Suspect the plastic lever is on the underside of that electrical connector, normally press the tab and pull the plug at the same time. You can use a flathead screwdriver against the side of the expansion tank and the sensor and tease it out. Don’t use force. More details here.

I think you’re worrying unnecessarily, 3k miles a year is very low. Actually, that can work against you with short runs and car not coming up to temperature. Just make sure oil is changed annually. 2017 Q5 is a timing chain too, so no belts to change other than auxilliary drive belt. Fuel filter on a diesel is every 20k miles, but suspect TFSI is in with the pump in the tank. Audi will no doubt says it’s non serviceable, but that’s not true and can be done, but hey that’s just me, especially given changes to fuel unless you run super unleaded all the time. Other than that, brake fluid every 2 years and keep air con serviced.

Absolutely. So my wife moved from an an A2 to a BMW i3 (perfect upgrade), if the A2 owners are evangelical, then i3 owners are like missionaries like Jack Hawkins in Zulu. I mean that in a light hearted way. They love their cars and are fiercely defensive of the marque/brand.

The A2OC are fairly evangelical bunch, and rightly so considering the last A2 rolled off the production line in 2005. We used to have a 1.4 TDI. Great cars but a little unrefined, but they were ahead of their time. Audi hated them at the time, especially main dealers as it didn’t fit the mould of the car range at the time. Back to this pipe. It reminds me of my brother’s Jeep Grand Cherokee. In his case it’s in the valley of a V6 diesel and the only way to fix is to dismantle half the engine. I think some owners resorted to changing the pipe to a more robust design as it’s a known weak point. I think your best bet is go back to A2OC as this is very niche. There must be lots of owners still about and have a wealth of knowledge on the fix. I hope you get it fixed.

If you remove the part, there will be an Audi part or VAG number on it. To be honest after market undertrays are cheap plastic. Search on EBay for genuine part, or a breakers years. One word of warning if you find anything on breakersyard.com, utter charlatans.

Make sure the fit a F.A.G. Bearing. Basically fit and forget. Car parts are not what they used to be, so cheap parts reveal themselves prematurely with normal wear and tear.

M12 or M10 - get a splined set.

Likely to be multi-spline bolts, 12 point bolt. You’ll need 1/2” ratchet, extension bar, etc. Very easy to cross thread when refitting, always hand start and don’t use power tools. Nip up at each corner. No idea if they use thread lock?

You need to get a pry-bar on the suspension. Arms are usually good for around 80k miles. Upper arms possibly. An inspection of the engine and transmission mount would be worthwhile as suggested. If you are changing arms, Meyle HD or Lemforder only.

On older tyres, it's possible to get flat spots, but that's not the case here. You definately want to be running with the same brand on an axle.