A4 Cabriolet.... Which Engine

Welcome to the forum.

Depending on the year you may be looking at a B6 or a B7. The B7 is clearly identified by the bottom of the headlights being curved (taller in the centre) whereas the B6 are reclangular and have a straight bottom edge. Other than that the cars are very similar (identical interior).

The 1.9tdi and 2.0tdi were never used in the B6 cab, therefore the 2.5tdi is the only B6 variant you will find unless you consider a petrol engine. I had a B6 2.5tdi (saloon) and it was a great car, but after having the HPFP fail on me I couldn't recommend it...

The B7 came with the 2.0tdi and the 3.0tdi, I have yet to see an A4 cab with the 2.7tdi although there are a few saloon/avants around, all be them quite rare. The 2.0tdi is a solid engine, however there are two variants, the 140 and the 170. The 170 (as you probably have guessed) has a higher power output, however this was subject to an injector recall which has been known to cause issues. So unless this has been rectified and there is a receipt from Audi, I'd steer clear of any 170's and try to find a 140. I have assumed both engines went into the cab, however I am not 100% on this.

Your other option if only looking at diesel engines is the 3.0tdi... I can wholeheartedly recommend this as an awesome engine and a brilliant combination with the auto gear box. More torque than an RS4 (when remapped), average 35mpg and they have very few problems. Only thing to look out for on a test drive is if there is any rattle (sounds like a clattering chain) when starting the engine. This should last for a couple of seconds while the oil pressure builds up, but if it remains after this time... walk away. If it's only there for a couple of seconds the cam-chain tensioner will need replacing at some point. I believe there are two and depending on which one has failed, it will either be a fairly simple job, or the entire engine will need removing to replace it, so be warned!

Having said all of the above, I've had a 3.0tdi cab from 108,000miles, now on 136,000miles and there is not rattle (even momentarily) and it's sailed through every MOT with no advisories other than wear and tear items. Always starts first time, brilliant car to drive.

Whichever engine you go for, if you're after low-end torque get a professional remap, don't bother with a chip. This will allow the turbo to spool up sooner in the rev range and give you the low end power you're looking for. It can also, if the power is used effectively through the gears, improve your MPG... however this is entirely dependent on your driving style!

Good luck in the search!

When reading these forums and looking about issues with different engines, it's always worth bearing in mind that most people who post on forums usually do so BECAUSE of problems, very few people pipe up to say that their car has been running fine for X years with no issues... so for every post about a problem, there are usually 10 happy owners with no issues!

Oh also, depending on what year you buy (I believe they started introducing them around 2006) any TDI has the potential to have a DPF fitted. This should be decode-able form the VIN, however I don't know what code to look for... either someone will be along to provide this info, if not give it a search.

These can be removed or simply 'emptied' and welded back up again. Technically your car will not be road legal and if a particularly prudent MOT tester can prove A) your car came with a DPF form the factory, B) it doesn't have one now, you could fail your MOT. But a visual inspection is all that is required. Note: I don't have one and I've passed an MOT with the new regulations.

If you get a car without a DPF, great, not problem for you. If it does have one, research about DPFs and how they need to be cycled to ensure they don't clog up. Regardless of how you drive however, they have a limited life. Depending on the engine the price differs, but it is usually upwards of £1000 for a replacement. Hence a lot of people combine a remap with a DPF removal/gutting as this also needs to be coded out of the ECU.

Hope this helps

Hi Derek,

Firstly let me say that the A4 Cabriolet is still a very stylish and desirable drop top. It's a true 4 seater, with a well insulated roof and decent size boot. But it is a cabriolet and that makes it a tad heavier than your average hatchback. It handles quite well.......in B7 form at least....but you may find the 140 2.0tdi to be a tad on the slow side.

Also, check out the threads on oil pumps and multitronic gearboxes before deciding on which model to buy - the 3.0d doesn't have any of these issues and comes in quattro format as well.

Whichever A4 cab you choose it will be awesome. Just get out there and enjoy it.
.

Can I ask your reason for a diesel?

I only ask because I looked at a diesel b7 cab and I have to admit it didn't quite do it for me (the full package). It was nice but when put against the 3.2v6 quattro I ended up getting, it didn't quite stack up. It's my first venture into German and the quattro is great, feels very planted. And the sound of the v6 is intoxicating.

Obviously if mpg is what your after then v6 maybe isn't for you but the are some good petroleum like the 2.0 tfsi. I would also say a wind deflector is a must, I bought one after and has made a massive difference.

I'm not that posh to say petroleum, ****** auto correct

Well mpg def makes sense. Try and drive everything. Plenty about. Go with what puts a smile on your face.

I second that......test drive them both. IMHO the later B7 car looks the dogs. The earlier B6 looks too dated for my taste. However.....if you buy a 2.0tdi then you will always notice its a 4 cylinder diesel as they're not as smooth as the V6s.

S Line spec is excellent and the Bose audio is tremendous with the roof down.....just be ready to be shaken on uneven roads with SLine suspension and 40 profile tyres.

Choose the best spec you can find as it'll make it easier to sell on after your 8 week treks.
.

I would go for the v6 tdi 163 Bhp if i were you, stick a remap and at 200 Bhp the engine is not stressed and it will still do 40-45 Mpg driven hard on autobahn. I drove both: 2.0 B7 cabrio- the DPF clogged after a failed turbo and even with a map and DPF codded off, it was still a dog to drive- the car is a bit too much for the weight of the car ! As above, go for manual in any instance, the auto CVT gearbox is a ticking bomb and will cost serious money to repair. If you're interested i have a friend that's selling a nice cabriolet, 2004, new clutch/flywheel, refurbished injector pump, runs very well- standard power though. It's high mileage but very well looked after and there are no bangs or rattles ! Genuine reason for sale- they bought a BMW tourer as they have a 10 months baby and no room for pram and extra parafenalia you likely need when kids are taken on short/long trips !

derekmines said:

For the avoidance of doubt I'm looking at the following 2 cars (both manuals, I've no interest in autos in sportscars)

Click to expand...

The A4 is not a sportscar, it's a medium sized 'luxury' sedan, of which there is a cabriolet variant.

Personally I would stay away from the 2.5tdi, partially because I wouldn't trust it at the mileage you'd be looking at, plus if you're doing lots of long distances the difference in MPG will be very noticeable.

The B7 will also hold it's value better, due to it being a facelift model and the 2.0tdi is generally more appealing to used car buyers due to the economy. The 2.0tdi with DPF removed and a remap I think would suit your needs, you won't notice the engine noise with the top down on the motorway and it comes with a wind deflector which is an added bonus.

Just my 2p and obviously it's your decision which one you opt for. I'm guilty of buying two Audi V6 TDIs myself so I'm a bit of a hypocrite!

What is not to trust on a v6 ? It has cam roller heads, the pumps are the last version with improved electronics, it's hugely de-tuned (so they could have sold the 2.0Tdi 140 Bhp), there's no DPF, injectors don't wear or short like on the 2.0Tdi AND they have no oil pump issues, turbo's are very, very robust and are in effect much more reliable overall ! Even the trusty 3.0Tdi is not as reliable as the old 2.5 tdi lump... i work on VAG cars day in/day out and at +150k the 2.5 v6 tdi is much more likely to give less issues...
I have a 2.0 Tdi in bits at the garage, massive rebuild as the chap is shooting for over 300 Bhp, spun rod on the crank and bearings US. It even had a new balancer shaft drive/oil pump 2 years ago but it did not stop it from failing ! About 2k in parts already for a ****ty 2006 b7 model ! My allroad v6 tdi is close to 300k without major issues, last 100k been running close to 300 Bhp and done hundreds of thousands of miles with cars on tow on a HD iffor williams trailer...

Not trusting the 2.5TDI is from personal experience... I had a £3.5k repair bill because the HPFP went at about 120,000. I think you've questioned the cost of this repair previously in an old thread adamss24, it was an Audi specialist who did the work, some investigation to find the fault, the front of the car was dismantled for a week or so, then had to be flat-bedded to Audi to re-code the supplied refurbished HPFP to the ECU.

At the time I read of several similar failures and as a result, perhaps unjustly, I am very reluctant to recommend that engine to anyone...

You will have similar xxxK bills with the 3.0Tdi, especially when electrics start to pack up and injectors/HP fuel pump are starting to go wrong. Let's not mention the particulate filters and chain tensioners, basic repair kit for that is £600 to buy trade, full kit is over £2500...

Nowadays you can fully refurbish a VP44 pump for a old v6 tdi for under £700 and to code it you just need a cheap OBD2 reader that can pull the Immo code from the dash cluster...there's no need to pull the front of the car to change a fuel pump !

When cars became 10-15 years old they became not economically to repair anymore...hence people trading them in !

adamss24 said:

You will have similar xxxK bills with the 3.0Tdi, especially when electrics start to pack up and injectors/HP fuel pump are starting to go wrong. Let's not mention the particulate filters and chain tensioners, basic repair kit for that is £600 to buy trade, full kit is over £2500...

Nowadays you can fully refurbish a VP44 pump for a old v6 tdi for under £700 and to code it you just need a cheap OBD2 reader that can pull the Immo code from the dash cluster...there's no need to pull the front of the car to change a fuel pump !

When cars became 10-15 years old they became not economically to repair anymore...hence people trading them in !

Click to expand...

Eeeek, you're making me nervous now, adamss24!

I did not know what to go for when i wanted a b7 cabrio. I am doing lots of small trips so a tdi as not really going to work for me. I went for a 2.0fsi but if i had my time again i would go for the bigger engine car, If it was down to a tdi then a 3.0 all the way.

3.0 tdi with map, imo, is the way to go. Car is way too heavy and cumbersome to ever be classed as a sports car but the torque of the 3.0 will put a smile on your face every time the road straightens out. I've got a 140 bhp Golf which feels pretty slow, that sort of power output wouldn't be too much fun in the Audi.
As well as being my first diesel car is also my first non manual, once you've tried a tip I'm sure you would like it. 3.0 tdi cabs also come in manual though.

I can vouch for the 3.0 TDI engine ( mines in an A5 Quattro and remapped) I drove to the south of France from Milton Keynes last new years for snowboarding and it was a dream ( apart from French traffic) and I managed 45Mpg on average.

The 140 tdi has just enough torque to move an B7 cabriolet. It won't win any traffic light starts but it can be hustled along nicely if kept on boost thanks to low down torque. 50+ mpg is also nice. My S Line handles pretty well considering it's bulk, with very little body roll - I had been reading the thread on S4 ARB but can't see that it's really necessary.

When you consider that the B7 cab is all about top down cruising in comfort and style, then the 140 begins to make sense.

But yes, a 3.0tdi s tronic make it an even more desirable drop top.

2.0 TDI's with the BPW engine suffer from camshaft wear at the 100k mark. Each cab I've fixed has had this problem !

VagPro said:

2.0 TDI's with the BPW engine suffer from camshaft wear at the 100k mark.

Click to expand...

100k ? There was a time when diesel engines ran reliably for twice that mileage with ease.

Is this service schedule (oil quality) related, or poor quality components?

And just the BPW 2.0 tdi engine....or others ?
.

I think its down to the long life servicing, poorly hardened cams and design of large cam lobes

The 1.9 PD 150 bhp suffers of the same problems