Rear Shocker top mounts
They wear out, check by lifting car up and down via rear
arch, listen for knock, don't be confused with the half
shafts catching though, you can remove the inside trim and
bounce the car looking for excessive movement in the
rubbers, but for £15 each ish, just get a set, various
companies do stiffer ones, but beware as it does make a
difference to the ride, you can hear more road nice through
the car for example.
Vanos
An obvious one. Evos have twin vanos, problems usually show
round 45,000 Miles, but cars advertised as having a new one
are not always a good thing. The usual issue is leaking
solenoid seals, a good independent dealer can replace these
for circa £250
Rear Arches
Check the rear arches for signs of rust, as they hold mud
and rot from the inside out, especially if mud and wet gets
behind the plastic covers and stills on the inside of the
wheel arches.
You can buy arch sections for about £80.00 but cost me £500
to have them fitted.
Exhaust
Rear box over £500 and Cats very expensive, they rust at
front and rear of the cat mount, where they mount to exhaust
pipe, check for blows, also on the Evo there is a flex piece
on one of the manifold down pipes that can crack / leak, and
the manifolds are £100 - £150 second hand and up to £800 new
so quite a hike!
Tyres
My E36 Buying Guide.
For a good set of Michelin Pilot Sports, They handle best
with these as were fitted std IMHO, you're looking at £600
Side Mouldings'
The M Sport mouldings' have metal inside them, these rust
and the clips break off, ensure all mouldings' are close to
the body of the car.
Rust
BMW's aren't usually too bad for rust, and most M3's if your
lucky have been looked after, if not, look for rust in the
following places:
Edge of bonnet, rear arches, around the BMW badge, around
the boot lock, behind the boot handle, inside the boot under
the boot seals near the lights, around the jacking rubber
points and on the two bottom corners of the boot edge where
the drain holes are.
A/C
(Ensure the ac blows cold as the ac system is expensive to
fix if there's a leak in the condenser unit, up to £500. If
its too cold the ac doesn't run, this is a feature)
Window Moulding's
A simple job, but the side rubbers by the rear windows
perish, makes the car look old)
Door Rubbers
If split, they are expensive to replace, as they could have
been letting in moisture, check under the cill trim as you
get in the car, as the holes where the plastic trim fits to
the cill can trap water and rust.
Electric Windows
Check windows go up automatically, if not the units that
control the window stop may have gone, which is a pain as
they wont close unless you hold down the switch, and full
closure alarms wont b able to close the window, nor can you
on the key.
Keys
Most M3's from 94 onwards have chip encoded keys that have
to be programmed to match the car, so if you only have one
key than can be expensive, just think cost of key + at least
an hours BMW labour to code it up. (used to be an hour don't
know now)
Alloys
If they have diamond cut alloys most reburbisher's will not
touch them, as the lacquer comes straight off again, and
also if they are damaged BMW charge a lot for a new one.
BMAutosport do a good selection of refurbished alloys
usually with tyres, between £500 - £700, don't skimp on
cheap wheels as they set the whole car off imo.
Front end
Check the bonnet catches are not to new, as these often get
replaced on front end shunts. Check inner wing seam welds,
should be neat and match each other, make sure all original
BMW stickers ore on the front slam panel, and inner wings.
Make sure bumper lines up, after shunts they can be loose or
uneven.
Gear Box
Watch the 2nd gear syncro, they can get worn when previous
owners have been snatching 2nd gear in the 0-60 dash.
Clutch
A clutch will cost you a good £500 to fit, if the car has
between 75K and 100K most are ready for a clutch
Hydraulic Clutch Pipe
As the cars get older the hydraulic clutch pipe can expand,
meaning the clutch can drag, a new pipe, or a braded updated
pipe from ebay or other websites is often a cheap fix.
Trailing Arm Rubbers
The rubbers on the front and rear trailing arms tend to need
replacing circa 75K Get a garage to check for you, you can
usually tell if it sides about a bit to much at the rear
under heavy acceleration or deceleration.
Lambda Sensors
They burn out round 60K and there are 2 of them.
SMG Gearbox
Check oil levels for the hydraulic system, as if its low it
will pop out of gear, can suddenly select neutral when
driving and give the occasional error code on the dash. when
warm get the car in sport mode (not manual) and drive it
hard through the gear range, ensure the clutch doesn't slip.
Interior Trim and Equipment
Check for standard equipment, as a BMW cd changer connection
lead if the car doesn't have one is a good £50.00 and a new
cd unit can be £300. Ebay is obviously a good place to get
things, but the e36 cd changers are rare. Look for signs of
paintwork, usual spots are round edge of windscreen rubbers,
under the rear lights on the rear 1/4 where the 1/4 meets
the rear panel, and inside the fuel filler area.
Exhaust Note
None standard exhaust tend to be too noisy, like the
scorpion type as they drown at motorway cruising speeds,
Thornely motor sport do some good performance bits I
believe.
Most of this stuff is obvious, but I've learned the hard way
Hope its of some use, if you want some more info, feel free
to email me.