Luey

Good question. I've run the car on Shell Ultimate Diesel for the last 5 months. I also add Redex about every six months as a part of my usual service. I've serviced the car about every 3000 since I've owned it. New EGR valve, swirl flap delete, clean manifold, etc. So everything should be burning cleanly I would expect. I also tried K2 DPF cleaner which is a spray in cleaner for the DPF. You add it through the DPF pressure hose. Zero luck with that. I guess at this point I may need a VAG expert to take a look.

I've wondered whether the differential pressure sensor could be faulty. Question: Did you have a fault code to say the sensor had failed? Also how often did you find it regenerating? I've got no faults at the moment. I also used my diagnostics tool to chart the pressure sensor on a drive. The values don't read anything crazy like negative numbers or sky high numbers. Yet obviously I can't say for sure whether they are in spec and reading correctly. I guess this is worth looking into some more.

I've posted on the forums a couple times in the past about an issue I'm having with me A3 8P 2.0 TDI (170) Quattro. I have now established that my DPF is regenerating every 30 miles... which is far too frequent. My OBDEleven diagnostics tool shows that the filter has 65 grams of ash and a -18% value... I'm not entirely sure if you are supposed to take the 18% value off the 65 grams to reveal a true ash load of 53%... zero information online I'm not even convinced these numbers are correct. I'm hoping someone knows how to establish whether a DPF is critically full of ash or whether sensors are reading incorrectly and need re-calibrating. Additionally, it would be helpful to know if you can reset the differential pressure sensor to recalculate the soot and ash loads? Also worth noting that there are zero fault codes on the car and the car always successfully actively regenerates fully. I've had a quote of £850 for the physical removal, refit and cleaning of the DPF... but I've not taken it for an official diagnosis yet. Any ideas would be appreciated. I've done two weeks of research and I'm desperately in need of help.

Sorry if it wasn't clear I put the engine model in the title. It's a 2.0 TDI 170 (Engine code BMN). So I guess a vaccum leak is a real possibility, or potentially the fuel / vaccum pump is failing. I really can't tell you what the fumes are sometimes it smells like burning oil, other times just smells hot, and others it smells like exhaust/diesel

Hey everyone. I wrote about this issue back in July My car has a strange issue with a rough idle and a hot engine smell After a long drive I can smell a hot acrid burning smell in the cabin The exhaust note drops noticeably however only at idle The car can vibrate ever so slightly too when returning to idle from higher rpms I have run diagnostics with no faults, and the car was seen by a VAG specialist garage I changed the EGR valve 5 months ago due to this issue and the problem seemed to resolve It is however now back, just not as bad at this time. My thoughts? Could the EGR valve have gone again? The electric mechanism of the last one seemed faulty and it was fully of black oil, likely the seal around the valve actuator arm had decayed. I'm not sure however why the new one would fail too. Seems the hot smell and sound happen more after applying the brakes hard The exhaust note may change slightly when the brake pedal is pressed too I wonder if a vaccum leak is actually the problem somewhere near the brake booster. Any ideas please share! Many Thanks Luey

Actually that's really helpful. I had a quick look but they seem more expensive than what I have found. My concern however is the cost of dropping the exhaust, then the propshaft... splitting it... keeping it balanced... fitting the new bearing then putting it all back. It's going to cost a pretty penny. I reckon within a year I will need a new clutch and flywheel. This car is seriously expensive.

Actually they couldn't find the fault and refused to charge me. Which was nice for my wallet. They have offered to take another look when it goes in for a routine cambelt and waterpump. However I am reluctant to spend the £400 on that without having this fixed first. On top of all this I need the prop shaft centre support bearing replaced. Which Audi no longer do... so have to buy the parts from Australia or aftermarket from US then another £400 to fit.

Hey everyone, Got another problem with my nightmare Audi. I have been to two experts and they don't have a clue what the problem is. After a drive, once the car is warm, the car seems to idle rough. The exhaust note drops and sounds throaty. I haven't noticed any smoke but that could be due to the DPF and I can't really feel a drop in power. After about a minute sitting the car very suddenly drops back to it's original exhaust note. Additionally a very faint clicking can be heard down the exhaust. However cannot hear anything out of the ordinary towards the engine. I also have a couple OBDEleven faults Cylinder 1 Injector short to B+ (intermittent) and IMRC Intake Manifold Runner Control fault also intermittent. Any ideas what short to B+ means and cause also IMRC I have no ideas about as I deleted the swirl flaps a year ago without issues. Throttle body? I suspect it could be a faulty EGR, coolant sensor, maybe injector? Can also have issues on rare occasions starting, super lumpy idle. I think thats a misfire on injector one. Which is showing as a fault on the first injector. However drives fine so not sure this is causing the issues with the sound when hot. Any ideas would be appreciated

Hey everyone, So I reckon my clutch is going but I would rather someone with more experience confirm my suspicions The clutch feels very dull, it is very hard to pinpoint a bite point. It feels as if the clutch makes contact lower on the pedal action but doesn't grip until much higher up. The clutch takes a long time to engage when pulling away, car does not like to pull away at speed. I have found it hard to change gears on a couple of occasions on cold mornings. It may have slipped a couple times but I am not certain: I have been driving up a hill before in a high gear suddenly to find a loss of power and a grinding sound, which immediately stopped when pressing the clutch pedal in. I have also been driving in a high gear and heard a similar grinding sound when forced to brake suddenly. Assuming again sudden drop in speed caused slip. I believe the flywheel is probably also pretty weak as the car doesn't feel smooth between gear changes or pulling away. I got a couple quotes already none of which are cheap... because Quattro... I just want some validation before I bite the bullet.

Sorry I forgot your second question. I'm not sure if your Q7 has a belt or a chain. I could tell just by listening to it. A quick Google search wasn't helpful. Some people seem to believe if you have a timing chain unlike a belt it never needs to be replaced. They're wrong. Timing chain tensioners fail all the time and timing chains can wear or even stretch. I will do a little more digging when I get more time.

Sorry I mean't to reply sooner. It's been a very busy 24 hours. I did some checking yesterday for you. The LION battery you have currently fitted is up to the minimum specification recommended by the manufacturer, however they are a cheap alternative. The BOSCH battery you just bought is perfect! It's got a few extra cranking amps and a little more power too and it'll be very well manufactured. I'm still betting the battery has died personally. It was probably poorly manufactured or something. Hopefully you can return for a refund if it had died already. Again whatever is wrong it absolutely can't be anything major. My Audi was poorly cared for by it's last owner, I like to think I rescued her, she'd done 29,000 miles without a service. She required a little love and attention but she's not let me down yet and every time I drive her I've had the biggest smile on my face. I've done most of the work myself using a £25 tool kit bought many many years ago from Aldi. Audi built fantastic cars, and they build them well, but as with any car they can have a problem every now and then. The only new thing I can think of you might want to check is the fans on the radiator. After you've been for a drive shut the car off and give it a minute or two, then go open the hood and directly beneath you will be the radiator. The radiator will have a couple of electric fans connected to it, see if they're still spinning, the circuit to them can breakdown and get stuck on which drains the battery. They might/should run for a little while after you shut the engine off to cool it down. However if they're stuck on after say 5-10 mins something may be wrong. It only takes a couple minutes to check and it doesn't cost you a penny.

Just want to tell everyone who voted RS6 with me I love you.

Quick update: I decided to give "Holt's Radweld Plus" a go this week to see if it would seal up the leak. It very well may have done the job and been a quick temporary fix to help me isolate the problem. I drained the coolant today and flushed the system through with clean water before refilling with fresh coolant. So a couple points: There was only a small amount of oil in the coolant that I drained not at all a concerning amount As mentioned on several occasions I'm trying to fix the problem before it gets worse The Holt's Radweld left an unsettling amount of sediment and I would advise everyone stay well clear of these products I flushed the system repeatedly to ensure none of it was left in the system We will see however now if any more oil appears in my coolant If none does either the Rad Weld work's and it's a small low pressure leak somewhere or the oil entered the system via mechanic error ...and by mechanic error I mean I used a dirty funnel or spilt a drop in the system unknowingly at some point in time I will update everyone when I know what's going on. I'm likely going to replace the oil cooler and the seal between the cooler and the block regardless as I suspect that's the problem. While I'm at it I'm going to also replace my boost hose seals and I will do a tutorial for the site!

I've just looked at a Rover 75 belt diagram. You have to loosen the tensioner from the top to loosen the belt then you just unclip the cables from the alternator undo one bolt and drop it out the bottom. It's not a terrible job but it's not as simple as my Audi that's for sure. Audi have a certain way of designing things. Audi brake calipers have a one man one toolbox system for example so you only need one set of spanners to undo a bolt you never need to spanners of the same end to hold the bolt while you undo it. They think of everything really. I guess that's more and more standard on European cars however. I'm sure you could find a mobile mechanic who'd do that on the cheap if you supplied the parts. My next project is fixing whatever is leaking oil into my coolant.

That's okay we all have to learn sometime. I will explain thing's step by step: When you turn the key in the ignition the battery sends energy to the starter motor, the glow plugs and the diesel pump The glow plugs warm up the inside of the cylinder to provide the heat required for combustion The diesel pump as the name suggests pumps diesel into the engine The starter motor cranks the engine to start it This requires a lot of energy, especially on a large displacement diesel engine If the battery isn't putting out enough power then your engine won't start The alternator plays no part in the starting of the engine. The alternator is basically a small generator When the engine is running the alternator generates energy and sends it to the battery to top up the energy lost from starting the car If the alternator dies the battery will not be recharged, it will run flat and the car will not start next time you turn the key If the alternator stops working the onboard computer should pick up that no charge is being sent to the battery If the alternator stops working the onboard computer should throw a warning to the dashboard The good news is they both commonly go wrong on virtually every make and model of car in existence. So manufactures design the both to be replaced fairly easily. Anyone can replace a battery following instructions on YouTube carefully. However an alternator is a little more tricky and usually requires a mechanic. However as they design them to be replaced it usually doesn't take a lot of work for a mechanic to get access to them and swap them out. I believe it's the battery that's the problem. Can you take us a photo of the battery so we can check it's suitable for your car. It may be too small and not holding sufficient charge even after only a few months to start the engine. Also given that it is now getting colder it will require more energy from the battery to start the engine.

Hey Moe I know what it's like to have persistent car troubles. It's likely the battery has died, sometimes they can be faulty, they often sell them with a warranty for this reason. Halfords will perform a free battery check and it shouldn't really matter what state of battery you show up with as they'll be reading the voltage. It could be the case that it's not charging meaning the alternator has failed, which would be more costly than a battery but not unreasonable if from a independent garage. If the alternator has failed you should have a light on the dash or a code stored in the car's onboard computer. Halfords may scan that for free for you too. I can't think how it would be anything insanely costly. If you find out what's wrong I can find you a replacement part on the cheap without issue.

Anyone know if there is any chance I exposed any coolant veins when I took the manifold off a couple months ago? I have attached a picture of the work. I would have expected if I exposed a coolant vein to have see coolant at some point. This is the only thing I can think of where I could have allowed oil into the coolant system somehow.

Thanks for the reply. Quick update: I called Audi this morning and got a quote for £320 for diagnostics. Obviously I won't be taking them up on that offer. I have called up an independent garage and got a quote for £39 for diagnostics and £119 for labour fitting a new oil cooler, which I would supply myself as I can get it for just £50 from Eurocarparts. They quoted me over £250 for the same part but said they'd happily allow me to supply it. Still making up my mind what I want to do but welcome any more suggestions. Magnet in response to your post. I really appreciate any help and advice. I have already fished out some "oil" with my finger. It's very hard to tell if it's actually engine oil. I can't think otherwise what it could be to be honest. I've also been trying to work out if I could have accidentally introduced oil into the system myself by accident. Which again I don't think is the case.

Hey everyone. I'm having some issues with my Audi A3 2.0 TDI Quattro... again! I really hope someone can help! I have a tiny amount of oil making it's way into my cooling system. I have provided details below and done a lot of testing and thinking on the matter. I have had the issue for about two to three months, but I haven't used the car a lot in that time. 1000 miles tops. What I know so far: There is a tiny amount of oil floating on the top of the coolant in my expansion tank There is less than a 10p coin size amount of oil floating on the surface The oil is not mixing with the coolant, there coolant otherwise is fresh and clean The car is not loosing any noticeable amount of oil or coolant at this point When running the car with the expansion tank open there are no bubbles indicating there are no exhaust gasses escaping into the cooling system There is no sign of any moisture entering the oil system whatsoever, no froth, sludge, nothing There are absolutely no signs there is anything wrong with the car and no performance issues I first noticed this issue about three months ago and it's seemingly not gotten worse My thoughts Wherever this leak is it has to be astoundingly tiny I believe if the head gasket had cracked I would not still be able to drive the car My guess is either the oil cooler has a tiny fracture or there is a leak in the rubber oil cooler gasket I'm not even certain it is oil if anyone has any other guesses, but I am fairly sure it is... If anyone has any ideas or thoughts please let me know!

Hey everyone, I've had the day off so today I'm replacing my plastic inlet manifold with a alloy inlet manifold, removing my swirl flaps, blanking off my egr and cleaning out the oily carbon deposits from this side of the system. I'm still putting everything back together but I thought you might get a kick out of the pictures! The last picture is my EGR valve at 114,000 miles, I will take some pictures from inside the manifold shortly. The moral of my story, if you love your car, either blank the EGR or clean your intake system!

I would suggest you find someone on eBay who is breaking the same car and ask if they have the part.

Often Audi quote two oil quantity figures for their cars. A wet capacity, if you fill the new oil filter before you put it into the engine, and a dry capacity if you don't fill the oil filter. I don't know if that could be playing it's part in this debate. However it's useful to know regardless. I always recommend fitting your oil filter wet too.

I believe it should explain the workings of you launch control in the owners manual. However what you'll probably find is; launch control can be very stressful on the engine, gearbox and drive train. Audi program in safety features to prevent damage to the car. You will find launch control will not work unless certain criteria is met. If the engine/gearbox is too hot it will not launch until it's had time too cool down. If the engine hasn't warmed up to operating temperature it likely will not launch either. A lot of people don't realise frequent abuse of Launch Control can damage your engine. Same way a lot of people don't know you need to warm up a car, especially a turbo charged car, before you can safely put it through it's paces. You'll find most modern cars have these fail safes and it'll prevent you having very expensive bills further down the line. It should also state in your owners manual that launch control subjects your car to heavy stresses and can increase wear and if improperly used cause damage. + If you're ever in Sussex please feel free to take me for a drive in your S4 Edit: Some rumours also suggest there is a limit on how many times you can use launch control. If you go over the limit your warranty is no longer valid or launch control will stop working permanently. They say about 200 uses apparently.

I am honestly stumped if there is no leak and it's not rattling on anything. I wonder if it's an exhaust valve sticking or something. It may not be anything that sinister. Have you tried running a shot of Redex through your fuel tank? I recommend it regardless it'll only cost a could quid. I do it monthly to keep my engine clean, obviously more effective on a diesel like mine but I've seen it make huge improvements in all types of cars.

I wouldn't advise measuring oil while the engine is running. At that point it's pumped a load to the top of the engine, into the filter, through the turbo, etc. It can remove quite an amount from the sump. You definitely don't want to overfill an engine. However it usually doesn't happen instantly so if you've put a little too much in don't panic straight away. Edit: Generally for damage to occur the piston rod ends would need to be hitting the oil. A whole litre more oil may not cause this to happen, but I wouldn't risk it and leave it in there anyway.