I'm a new guy looking to búy a Gen 1 3 MPS, so seriously appreciate your guide. Something that I feel would be useful, if possible, is some guidelines on timescales for the problems. For example, tyre wear, how long will a set of front tyres last in normal road driving (where normal no doubt equals 'spirited' for at least some of the time). As a quick aside, i had a 58 plate mazda 5 sport company car with 17" wheels and major front inner tyre wear problems (14k miles and 1cm inner strip down to convas whilst rest of tyre looked perfect), rear wheel adjustment was the only thing to help after months of trying, but it just meant frying one of the back tyres instead, due to limited rear suspension adjustment options)
Same question on the turbo oil seals, should I be seriously concerned about this in a 40k, 50k 60k , or say 80k car?
THanks again!

Buyers Guide - first draft!! (work in progress due to time restriction)

This is based on my 2.5 years experience (& just over 30k miles) driving a mk1 3, as well as reading this forum daily. Please feel free to add or expand any points missed, but keep factual and to topic, rather than turn it into debate or general banter.

One of the most important things to consider is the timing chain and Variable Valve Actuator (VVT). I list this first as it is potentially the most expensive. Early cars are most prone to a VVT fault and/or chain stretch. There was a revision to the VVT at chassis no. ???[can someone state chassis no.] However, even cars manufacturered later than this can suffer as the revised part is still not perfect. It is a noisy engine, so don't expect it to be silky BMW style smooth. However, if you can hear chain slap after start up, this is not a good sign. Other than on the mk2, it is possible to feel the chain by putting your fingers through the oil filler (obviously with the engine off and cold). However, as the VVT actuator requires oil pressure to work, then a slack chain when cold is not unusual. The definitive way to check the VVT is to remove the chain cover so you can both check for contact marks on the cover and check that the chain is on the timing marks as per the mazda service bulletin[can someone insert a link]. However, it is not practical to take the engine apart when viewing a car prior to purchase. The best thing is to give the engine a good listen to, and to have listened to a view videos of noisy and good chains first so you know what you are looking for. It is also worth checking the service history to see if it has already been changed. At the time of writing, Mazda will charge £1,200 for parts and labour to change the chain and VVT, but the parts are available from the USA (Edge) for about £300 and a local garage should be able to fit them for about the same. In principal it is the same job as doing a cam belt, so any competent garage should be able to do it. A special tool is required, which is the same special tool required for the same job on the 2.3 Ford Galaxy engine, so it is not too difficult to obtain.

The next MPS issue is the turbo. The standard K04 turbo has weak oil seals. These seals are under most pressure when the engine is idling as there is no pressure on the exhaust side of the seal. Let the engine idle for ten minutes and then rev it hard (stationary, no need to drive off). If the turbo oil seals have failed, it will be obvious - lots of very smelly very thick smoke. A little haze is nothing to worry about. There are a few short term solutions, such as fitting a banjo bolt and raising the idle speed. These may remove the symptoms, but they will not actually fix the turbo seals.

Tyres. On the 3 at least [not sure about the 6 - can someone say whether the same applies], the front tyres suffer very heavy wear on the inside edge - even if the tracking is correct. It does depend a bit on the brand of tyre (or the hardness of the sidewall), but when checking the tyres, look on the inside edge of the front. It is not uncommon for the inside edge to be completely bald, even with good tread over the rest of the tyre. On a 6, because of the AWD system, it is essential all 4 tyres are the same brand, and have similar wear.
Standard tyre size is 215/45/18. Many cars have now been fitted with 225/40/18 as there is a much bigger choice of tyres in this size and hence they are a lot cheaper. No downsides to this, but do tell your insurance company and do make sure all 4 have been changed.
Also, look closely at the wheels, which are prone to corrosion.

Suspension. On the 3's[again, can someone with a 6 confirm / deny], the suspension tends to be noisy. Not the end of the world, but a good haggling point. Drop links and antiroll bar bushes can be considered as consumables. Allow an hour or two at each end to replace, so no big labour charges, and the parts are not too expensive either. If it is still noisy, it will most probably be the shock absorbers (dampers) or top mounts. If you are changing either, then change both, as it is the same labour for both jobs (you remove them from the car together). Leaky shocks/dampers are not uncommon.

At the time of writing the oldest MPSs are approaching ten years old and the youngest are a couple of years old. They do suffer from rust. This is common behind the front and rear bumpers and bumper bars as well as on the arches and tailgates. Have a good look everywhere underneath, just like any other older car.
rust

On a 6, check the AC works. There is a pipe that commonly fails, that lets the gas escape. Not exactly sure of price, but budget for £200[can someone confirm / deny].

On a mk1 3 (not sure about the others), the front fog light lenses are prone to stone chip damage as they are low down. The lenses are not available separately and the complete fog light is £150 a side. Make sure they are not cracked; as they are low down, this is not always obvious unless you check specifically.

Many cars are tuned. Some are returned to standard before sale, some are not. There is loads of info on this site regarding tuning and it is not my intension to repeat it all here. However, if it has been tuned, the most important thing is "who did it" and "what has been done". Make sure you know, as that is your starting point. Also, don't believe any statements about what power it makes, unless backed up by a rolling road print out.

The cars are due a serviced annually or every 9k miles, whichever is the sooner. They are also due an initial service at 3k miles. So the schedule is 3,9,18,27 etc. 54k is the big one, which includes spark plugs, air filter, brake fluid change, gear box oil change etc. 72k is also big and includes a tappet check. There is no service book (other than on the very early cars) as mazda has introduced a digital service record. Independent garages can update this, but few of them do. Therefore it is not uncommon for cars not to have a full mazda digital service record. However, as long as the car has been serviced, and there is a bundle of receipts and invoices proving this, then that is what is important. It is worth remembering that you can go to mazda and ask them to print out the service record of any car, so you can check before buying. This should also include any work done by a mazda dealer, not just routine serving. The MPS engine is fussy on oil, don't put any cheap oil, but use quality fluids.

The differential can be noisy [on a 3, not sure about a 6], especially when on full lock. This is common, although actual failures are rare. It can often be cured or improved by changing the oil. Like the engine, the gearbox is very sensitive to oil. Use the noise as a haggling point.

Many of the early cars are in a high tax bracket. This puts a lot of people of buying and holds prices artificially low. Bizarrely, unless you do a tiny mileage, the cost of tax will be trivial compared to your fuel bill. If you find a low tax car great, but don't be put off by a high tax car and use it as a haggling point.

Finally, the above is intended as the relevant points to look for when looking at an MPS. You still need to check the things that you would check when looking at all performance cars for sale of equivalent age. MOT history, accident damage, condition of paintwork and interior, do all the electrics work, does it leak oil or water etc etc etc...

I hope this is of use to any potential purchasers. If anyone can add to the above, then that will help. Please keep it factual and on topic.

Edited for spelling / grammar