E39 BMW 5 Series
basic detailed checks for buying a late 6 cylinder petrol (UK 2000-2003)Introduction:
I've been working on a quick check list guide to cover most of the important things to check when buying a less than perfect facelift build of the 6 cylinder petrol BMW 5 Series E39
that I wish I had to hand when I was originally buying. Probably gone a bit further and deeper than initially intended (Warning, may induce nightmares
) and keep in mind that forums only tend to attract negative problem reports. Good cars but they are quite complex machines and getting on a bit now, if not properly maintained can become a rather large frustrating money pit (see this historically accurate ranting video clip
A very big thanks to all the info referenced here and to those that contributed over the years.
June 2011 update, managed to fix many of the reference links. Sadly a forum software upgrade destroyed all related thread links, useful image uploads in many historic posts (which is a great shame) and temporary loss of Google ranking. ...and that's a hell of a price to pay for being STYLISH!
- Dirty Harry (The Enforcer 1976)Which E39 to own?
Personally I think and the general consensus is that the preferred 'best all round package'
is probably the latest 530i 6cyl E39 5 Series
you can find (facelift Sept 2000-2003
), preferably sport if the ride suits your speed bump pothole damaged UK roads
and manual if that suits your driving style. Or if you prefer weekend fun and lower mileage use then a 540i (V8 4.4L
286bhp/440Nm ~6s to 60mph 23mpg) might be more up your street
or maybe chasing the perfect pricey Champagne II limited edition (I and II)
(or even Aplina
and M5 variants
with noisy vanos
). Or see this handy brief 530d buying guide and diesel advice
(check this Diesel vs Petrol payback calculator
). It's getting very hard to economically justify choosing a diesel if your UK mileage is less than 10K a year given the extra potential maintenance issues of an older 100K+ diesel motor when compared to a smoother relatively less troubled 6 cylinder petrol engine (at current fuel price differencials and initial premium cost loading etc.), where the time to payback in the real world probably isn't worth chasing. The debate rolls on
In September 2010 starting around (GBP)3K plus but do research each car as there are plenty of lemons out there (even if they still look pretty). The E39 can have a lot of hidden faults
, with more (GBP)500+ problems than you'd expect and you'll often get fleeced when trying to get faults repaired
(HOW MUCH? yea, mug me). Anything that seems slightly dodgy or sometimes too good to be true, walk away or at least take time to think it over and get second opinions. Even if problems are identified, the cost to fix can easily be double your initial estimate in reality. They say to 'buy on condition over age/mileage'
, though a younger well looked after model that is closer to 100K miles should be a better bet (post a full and proper Inspection2 type service
), whilst some still going strong at 200K miles plus
. Check service book stamps and contact previous dealers to verify history at service mileage intervals (if genuine
Also beware of low mileage examples that may have been left standing for long periods which may have extended times between services (oil sludge problems
, see this rather extreme case
), where a more regularly used higher mileage E39 could be a more reliable
Don't forget to check the Cars for Sale
section on this forum. There are hundreds of 5's for sale on Piston Heads
(these links should point to BMW E39 defined UK searches), seems to be a noticable large glut of late 520s at the moment (June 2011). So take your time and get a exactly what you want at a good price. No need to rush, who wants thirsty old motors with potentially high running costs these days? Note that there are a few adverts with very hard to believe low mileage claims with visible wear of similar cars with 3x the mileage. Some of the car adverts have been on there for over a year and not sold (which is probably not good for the mechanics of the car when left statically parked for long periods).Video of various E39 BMW 5 Series: (please PM me to make corrections)
# BMW Series 5 - E39 hommage to best car ever made.
# 2002 BMW E39 5-series Commercial.
# 2002 BMW 5-series Commercial.
# BMW Series 5 - Nothing is perfect (weird but I like it). # Italian version
# Old Top Gear - E39 BMW 5-Series road test. Jeremy Clarkson reviews a 1996 Pre facelift 528i Auto.
Test Drives and Walk Around / Look Over:
# Test Drive: 2002 BMW 525i US Auto (slight bad tyre rumble or slight wheel bearing noise maybe?).
# 2002 BMW 525i Start Up, Engine, and In Depth Tour US. Ignore the 'go faster stripe'.
# BMW 525i E39 auto driven hardish.
# City and motorway driving in a BMW E39 540i.
# E39 525i short drive (auto).
# 2002 BMW E39 530i auto, look over tour, 150K and trying hard to sell.
# BMW 535i e39 older 1996 V8 auto at 178K miles, brief tour with engine idling.
# BMW E39 Sold, US 528i auto, good look over with engine idling.
# Bmw 530d e39 full option 2003 edition, auto, look around. I've never seen one but does a diesel sound like that?
# BMW e39 520i 2002 170hp, brief tour, something chirping on start up, probably the secondary air pump under front corner that helps the mixture for the CAT get up to temp quicker and stops in seconds (or might be noisy auxiliary belt tenssioner, alternator on a soft battery).
# 2002 BMW 540i Sport (SOLD), 540i Auto SE V8 quick sales tour.
# BMW 540i E39 - SPORT PACKAGE 6 speed manual, 2001 stylish look over.
# 1999 BMW 540i E39 M62 6-speed --- PART 1 ---(walk over), # PART 2 (test drive), # PART 3 (more driving).
# BMW 540i vs Integra, bye bye. Loads more like this out there, seems owners can't resist posting videos of their speedometers climbing.
# 2003 BMW 525i, # 2003 BMW 530i, # 2003 BMW 530i, # 2003 BMW 530I, # 2003 BMW 530i, Loaded
M5 in detail (E39 BMW 5 Series):
# Old Top Gear - BMW M5, by Tiff Needell in 1999.
# 2000 BMW E39 M5 Review ~ Part 1/2
# 2000 BMW E39 M5 Review ~ Part 2/2
# 1998 BMW M5 5.0 V8 Full Review,Start Up, Engine, and In Depth Tour, includes the noisy Vanos gears/chain, common fault and only sounds bad apparently.
# BMW (E39) M5--Chicago Cars Direct HD - SILVER, US sales pitch, look over and test drive *good fun!*.
# BMW (E39) M5--Chicago Cars Direct HD - BLACK, US sales pitch, look over and test drive.
# E39 M5 "Star" Madonna Guy Ritchie BMW Films (*classic M5 cinema action*).
Alpina B10 (E39 BMW 5 Series variant):
# Old Top Gear - Alpina B10, by Jeremy Clarkson.
Diagnosis by video/audio:
# 2002 BMW 525i E39 Engine Sound at normal idle.
# BMW E39 2001 525i Ticking Idle and Engine Smoke! Not so good. The lower deeper tone rattle at the front of the engine was probably a near death worn water pump bearing. Distinguishable from the higher tone tapping hydraulic cam valve lifters heard from the side (oil pressure or viscosity problem).
# BMW 523i e39 Soundcheck (Motor), not sure but could well be the CCV (crank case breather system) oil separator (with a split diaphragm) that's making a horn like sound on pre rev vacuum, one of a few possible malfunction symptoms. Lots of other random diagnostic comments where posted ranging from Vanos variable cam shaft timing (oil seals) to DISA intake butterfly valve, all probably guessing wrongly (also hear this # 528i CCV noise). Read on...
# E39 Ticking, This can't be good- water pump again. Read on...# E39 Cooling System Overview with Common Failures Video# BMW E36, E46, E39 Belt & Pulley Failure VideoBasic preparation and info:
Before viewing, find out how to check the water
and oil levels
on E39s (different if not seen before, see video
), so you'll look like you know what your talking about. Then familiarise yourself with some of the spec features, differences between Sport and SE
versions, facelift change over and differences
etc. (US info here
). Helps stop the dealer/seller from giving you a lot of misinformation about what your actually looking at. Also be aware that some sellers will claim to have extra optional features fitted when they are actually just listing standard equipment on that years model or claimed optional equipment that is not actually fitted on the vehicle and may be used to push up the price for unsuspecting buyers (so don't believe the hype!). Start here BMW 5-Series Saloon (96-03) - Facts & Figures - Equipment (Parker's)
(or quick ref thread
) and wiki/BMW 5 Series (E39)
Other items of interest: The OBC (On Board Computer) stores a history of fault codes which can be read out for +(GBP)30 at a supporting garage (OBD2 scan is a revealing diagnostic aid
). Oil changes
every ~15K miles or sooner with age (when using 5w-30 fully synthetic oil eg. Castrol Edge
). Oh and the battery is in the boot (located in the driver's rear quarter), emergency jump start terminal connections on top of engine and in engine bay, the engine and radiator is air cooled by the old fashioned viscous fan method, the oil filter is at the top/front of the engine (6 cyl) and windscreen wipers are continental LHD which sweep up backwards from right to left
. The indicators are completely normal (if a bit noisy) but be aware that due to BMW etiquette it might be frowned upon if you get caught using them in anger (bit of a myth as most of those a**holes tend to drive Audi's now anyway LOL).Phone the seller and get the required information to:
- Check the current MOT status and MOT history of a vehicle for free: http://www.direct.go...ngAVehicle/Mot/
and might help locate missing advisory notices. There is a small dash tamper dot warning
next to the mileage that will illuminate red to indicate a possible mileage mismatch but I expect anyone who really knows what they are doing could defeat this feature. In 2010 there were over 600,000 cars
in the UK that displayed a lower mileage than recorded a year earlier
, that's more than 1 in every 4
new cars sold that could be clocked at some point in their history
(say 2M new cars sold per year and if 600K older cars are clocked each year ?
maybe), not to mention those clocked before their first MOT at 3 years old and any inter year rollbacks that don't go negative :!:. See this BBC article on clocking
. Great to see the DVLA/VOSA are doing so much to protect us
NOT. More from Auto Express here
and BBC WatchDog
.Clocking Update: BBC reports that over 1 million vehicles clocked
in the the year to May 2012, of those effected vehicals that can be officially identified by HPI/OFT (Office of Fair Trading). Seems the problem is only getting worse.
- 'Vehicle Enquiry' to check the details held by DVLA match the log book (V5 documentation): www.taxdisc.direct.gov.uk/EvlPortalApp/
(click 'Vehicle Enquiry').
- BMW VIN Decoder
, simple and free and worth a try for a little extra piece of mind.
The UK Road Tax increased by +(GBP)40 per year if the car was registered after 1st March 2001 to 1st June 2003. See this 530i example (GBP)245 per year (in 2010, see 'K' band here).
I think this info may be out of date.
In case your very new to cars: 'i'=petrol injection, 'd'=diesel, 'A'=auto transmission, 'Sport'=slightly extra spec than an SE
. Technicality, there is no such thing as an "M Sports" E39 (E60 marketing). 'RWD'=Of course E39s are Rear Wheel Drive
- Free ballpark valuation guide price estimator
, sadly they changed the site functionality but you can just make up some info to get a quick on screen reference.Documentation and Information:
- Download model specific PDF Owners Manuals
(handbook user guide).
- Golfpro's Greatest E39 Articles in PDF form for you to Download
. 100s of Magazines full of the great E39 throughout them with write ups, repairs, improvements, many of these cars belong to the members here.
Magazine article - E39 Ultimate Guide June 2006.pdf 1.64MB
136 downloads Best car in the world? Probably, and now possibly the best used car in the world. here's everything you need to know about the last car you'll ever need to own.
- Free BMW 5 Series (E39) Service Manual PDF download
(follow link and try link in the last or most recent post).
BMW 2001 Service Checklist.pdf 22.59KB
BMW 2001 Service Checklist.pdfThings to check overview:
In summary, look very hard at the overall condition and history, the engine and *cooling system*, electrical systems, suspension and as age becomes a factor, transmission wear and corrosion issues
. Some items are much much more important to check than others, so search the bmw5.co.uk Forum
for more info as some issues can be varied and wide ranging than mentioned here.On viewing and test driving (2000-2003 facelift, 6 cylinder petrol), be cautious and check:Cooling system:[ ] -
Cooling system solid and temperature gauge nailed to 12 o'clock at all times, no overheating. Cooking the Aluminium engine is possibly the number 1 cause of E39 death after 'hole in wallet disease'
.[ ] -
Not too much smell of sweet coolant around the engine bay (white staining) or out the exhaust (head gasket) loosing water coolant.[ ] -
No noise/rattle from the water pump, if heard then statically check for shaft/bearing wobble when yanking fan blades. A water pump change can lead to precautionary cooling system overhall
(safe guide every 70-80K) and change of radiator (plastic banana swell bulge and sag at base
), reservoir tank (brittle), thermostat and housing, Aux belt, viscous fan, pipes etc. (see brief assessment here
). A relatively high pressure cooling system is required to maintain adequate cooling of engine internals, sadly it's the high pressure design that often causes the dramatic failures. Read an example of 530i cooling problems here
. Would be nice to see documentary proof of recent maintenance (or around (GBP)500 with genuine parts fitted), assuming no permanent damage had occurred as a result. See # Cooling System Overview with Common Failures Video[ ] -
Auxiliary drive belt condition not cracked up (easy to see) and quiet tensioners. See # BMW E36, E46, E39 Belt & Pulley Failure VideoEngine observation (6cyl petrol):[ ] -
No oil/fumes in water, head gasket or cracked/warped head from briefly ignored cooling system failure? Aluminium engines seem more cost effective to replace than to fix (as failures can often return, ali warps, head bolts can snap or block threads can strip). If suspect then get a head gasket sniff test and piston compression test to save guessing and future worrying. Bullet Proof
they are not.[ ] -
No large amounts of brown mustard mayo (emulsified oil and water) in oil filler cap or on dip stick, check not prepared or wiped clean. Note that short trips in cold weather
may also deposit mayo under filler cap (use judgment), sadly burning petrol in air also produces water as steam that blows past the pistons, condenses to emulsify with the oil.[ ] -
No idling issues or revs pulsing, engine should be smooth all the time (eg. inlet and vacuum air leaks, coil packs, various ECU sensors to worn Vanos oil rings
).[ ] -
Check engine revs freely and will sustain over 4K rpm (or possibly a blocked Catalytic Converter could be pressurising exhaust system).[ ] -
No top engine rattle (HVA - hydraulic bucket tappets)
off the ignition key and oil light goes out quickly (when hot and cold).[ ] -
No noise/rattle from the Vanos variable camshaft timing chain area (front end
of cam shafts, full details here
, malfunction symptoms
).[ ] -
Very fresh oil may be suspicious, using a lot which you only find out by owning (eg. leaky dipstick seals, CCV breather
malfunction to worn piston oil rings
causing burn off).[ ] -
Cam/valve cover gasket (rocker cover) not leaking oil onto exhaust down pipes at rear of engine bay, commonly producing visible vapour after a run as oil leak drips down and burns, may also observe fried oil staining on heat shield. A relatively cheap repair but the situation may be caused or aggravated by a blocked/broken CCV breather
system (oil Separator) if crank case pressurises.[ ] -
Various CCV breather failure symptoms (Crank Case Vent to inlet recycle system) ranging from increase oil usage, occasional white smoke clouds (surprisingly as oil burns), nothing happens to idle rpm when oil filler cap removed (lack of mild cap suction), dip stick pipe gargling. See the story of mine here.
Or see another type of CCV failure here
. More info here
and here (plus useful links)
. DIY Replacing the BMW M54 Crankcase Ventilation System, see videos -1-
.Suspension evaluation:[ ] -
When driving the ride should feel firm with stable handling (especially on those twisty 'A' roads), steering is precise and accurate, brakes are sharp and progressive, engine is responsive and pulls smoothly with consistent performance. Like a good E39 5 Series BMW should
. Although pretty smooth, when compared to other family sized 4 door saloons, you should notice that the handling has less body roll and less dip/rise during braking/accelerating, in my mind the car has a flatter profile and more of a kart
like feel than you might expect, even with the softer SE version on standard 17" wheels
and tyres (slightly subjective drivel noted).[ ] -
No suspension knocks driving over small potholes or over large speed bumps, they'll always say it's Anti roll bar bushes! oh yea? Another large and varied subject area that can be costly or could be as basic as stones trapped on wheel hub
. Don't test drive too delicate but with some spirit. Also try to partly test with the AC/fan and stereo off and the windows down, go through the gears with pace and power whilst listening for any odd noises, squeaks, shimmy, squirming, vibration, mechanical whine or knocks over a variety of road surfaces, preferably in dry weather or the wet tyre noise may hide more subtle problems.[ ] -
Check brake discs for excessive edge lips, scoring and pad condition, inner pads seem to wear out first, expect auto's to wear quicker than manuals. Excessive shimmy under strong breaking down from 70mph (a fussy setup and not always brake discs or any obvious cause, can be costly to chase such niggles - thrust arm bushes
, wheel balancing, track rod ends, wish bones, hubs etc.).[ ] -
Vibration at speed (50-80mph) can often be due to the E39's requiring fussy wheel balancing (or sometimes prop shaft rubber doughnut). Cheap enough to fix so request the seller corrects in advance to rule out more serious causes
.[ ] -
Check Ali wheels for impacts and cracks that can easily spread with time, particularly inner rim damage (can be hard to see). You don't want to be trying to find a single matching wheel for a rare BMW style
.[ ] -
Check condition and brand of tyres. A good set of 4 can cost +600 to replace, 4x budget rubber can be closer to (GBP)300 (eg. FALKEN FK452
, FALKEN ZE912
). Signs of uneven tyre wear could point to worn suspension bushes, joints and awkward to identify geometry issues or just be basic 4 wheel alignment. A good brand of rubber may be an indication
of the owners general attitude toward car maintenance.[ ] -
Some older BMWs may visibly sit up to 20mm lower on the drivers side (OSR/OSF)
, without an obvious cause or simple cure. Very sad!Other general things to check and consider:[ ] -
Engine is stone cold before your viewing starts, so request by phone/email before hand.[ ] - Battery weak or dead
(may have corroded battery terminals or faulty ignition key electrical switch. Commonly a faulty FSR - Final Stage Resistor 'Hedgehog'
failure causing odd internal fan activity and random battery parasitic drain
, more here
, aka FSUnit).[ ] -
All the warning lights on the dashboard function before starting and go out as expected (with none conveniently missing/covered up
or dead), otherwise try to diagnose with an OBD2 scan of stored fault codes at a supporting garage. See specific Owners Manuals
and confirm most dash bulbs with the TEST-NR. 02 (Instrument cluster test)
, see more info here.[ ] -
The two yellow/orange ABS/DSC/Traction control lights are working and go out off the key. A dodgy seller could blank out the warning lights due to the ABS control module failure as hard to repair PCB design gets cooked in exhaust manifold hot area. Common failure (GBP)150 to (GBP)400 plus diagnostics and new unit re-coding to fix, otherwise will fail next MOT. Can also effects speedo and cruise control functionality. May be a wheel sensor or relator tooth wheel contamination if you are lucky. Get codes read etc.[ ] -
The dash mileage tamper dot
next to the mileage is not illuminated red. See this BBC article on clocking
.[ ] -
The meaning of 5 fresh GREEN service lights (anyone can reset them
, more info here
).[ ] -
Claimed low mileage and worn inner door seals
, weak seat belt return spring and peppered with lots of stone chips. Front bumper, bonnet, headlights, wing mirrors and thin windscreens can have noticeable impact damage at higher mileage above 100K (relative judgment I guess, see age related thread
).[ ] -
Nice to see a history of receipts, past MOTs and any advisories.[ ] -
Head lights and all lights work correctly, no lenses fogged with condensation (can fail MOT). See tips here
.[ ] -
AC and heater works correctly. The AC snow flake button causes Aux fan to kick in for the AC condenser in front of main radiator after a few minutes if set to lowest temp (or refrigerant may overheat and pop), the Aux fan is also a backup aid to extreme stationary engine cooling (assuming the AC has no other errors, so not necessarily an aux fan failure).[ ] -
PDC arms reliably without fault beeps and flashing LED
(normally parking sensor(s) or wiring fault).[ ] -
Check all the in car switches and buttons, windows and locks function correctly.[ ] -
Check condition of spare key(s) and all the central locking works.[ ] -
Check the wheel locking nut spline tool
is in good condition (along with tools held in boot lid) and spare Ali wheel under boot floor.[ ] -
Check the radio/CD and all speakers work, yes the basic stock ICE radio sound system really is that bad in these cars (add boot sub woofer
). Unit faults and cut outs are common, a reflow of internal dry solder joints can sometimes restore.[ ] -
Cup holders and AC buttons not broken
or cracked (cheap enough but annoying). Floor matts worth having?[ ] -
Common to find missing / dead or fading pixels on the Instrument Cluster or Multi Information Display (MID)
, if fitted. Newbies should see the brief description of Hi/Low OBC (On Board Computer) types and MID
abbreviations and acronyms. More OBC info in threads -1-
.[ ] -
What else could a sparkling clean engine bay say (may be trying to hide other fluid leaks)?[ ] -
Don't trust the hand brake
(may only hold the car strong enough against one direction when warm), more info here
.Check common areas for rust corrosion: [ ] -
Petrol filler cap, rust bubbles at seam, area pools water (poor design, greese hidden area periodically).[ ] -
Bubbles around boot lid handle, rear number plate lights and boot key hole.[ ] -
Around the rear slam panel, above the bumper where the boot shuts.[ ] -
Check for bubbles around windscreens.[ ] -
Bonnet front catches/mounts can corrode.[ ] -
Occasional sill/skirt spots, sill front edge to wheel arch, rear arch bubbles.[ ] -
Around rear door trim strips.[ ] -
Check for damp carpets and wet kick plates after heavy rain, could be the door vapor barrier leaking
More rust experience here
, do not puncture or curb/kerb damage sills.Notes:
Even more issues that might pop up if you read through the what on your e39 doesn't work or needs replacing...?
Although I will personally always prefer a manual gear box, try the E39 Manual gear box and clutch, picky observations
thread (high mileage).Note: There are some extra checks for Tourings (the estate version), Auto gearboxes (sealed for life - transmission fluid change?), V8s and Diesel Turbo engines (nice 530d guide and see here, remove Swirl Flaps, thread3) not listed in this post (no reliable knowledge personally ).
Please add extra info and links if you know more or PM me to make corrections, additions and updates.
Hope it helps (could save a fortune), print the various checklists, happy haggling, good luck and spread the word.
Go here if you would like to donate to DarkHorse
(zero to date in 3yrs, you lot are very tight, ...I'll never get that Sport).
.More Online E39 Buying Guides:
Also see Honest John's: BMW 5 Series E39 (1996 - 2003 )
, also click the other tabs.
Some more brief E39 buying advice here.
There doesn't seem to be that much buying info 'out there' but I did find this quite relevant (in state side english), so I pasted the text here to preserve the info if the link dies.Getting EDGEucated: The "75k Mile List" The E39 5 Series (1995-2003, including M) EditionThrust Arm Bushing Failure : The most common suspension problem on the E39. Common symptoms for torn or cracked thrust arm bushings are shimmy under braking at freeway speed. vague or rubbery feel in the steering, and excessive front tire wear. Extreme examples will also produce a clunking sound. EVERY 5 and 7 series car we have ever seen needs these replaced by 75k. Many need them by 40k!!Tie Rod Wear : V8 Powered 5 series cars share many basic front steering components with the 7 series cars, including the recirculating-ball type steering gear and a tie rod end attached to each end of the center tie rod. The tie rod ball joints and idler arm bushing are prone to wear and any one of them may cause excessive tire wear and/or steering shimmy. If any of the ball joint boots is cracked (you'll see grease coming out) then expect that component to need replacement eventually. All components should also be checked for excessive play, and replaced if necessary.Worn and Loose Rear Ball Joints : The E39 5 Series shares rear suspension geometry with the E38 7 Series, including rear suspension components. The rear suspension joints are critical to maintain the alignment and stability of the vehicle. Worn components can cause unstable handling and excessive tire wear. As the E39 approaches 100K miles, expect the rear ball joints to wear out and need replacement.Worn or Blown Shocks and Struts : Factory BMW shocks on the 5 series cars are very robust, frequently working adequately for over 100K miles. They do wear out though, and most folks who have been driving their cars since new hardly notice the deterioration as it is gradual. Symptoms include:Diving under braking and acceleration, excessive lean and suspension compression during cornering. Bouncy and uncomfortable ride. Shocks and struts may also visibly leak shock oil. On the E39 5-Series, EDGE generally recommends replacing the factory units with either new factory shocks or with Koni Sport shocks. When replacing shocks and struts at 100K or greater, the upper shock mounts, both front and rear may also need replacement. This is a great time to install lowering springs or freshen up other areas of the suspension as well. You will be amazed at the difference a good set of shocks can make in both comfort and performance!Worn or Failed Swaybar Endlinks : Worn swaybar endlinks can compromise handling. A worn swaybar can sound like a metallic clicking noise. There is no critical danger in a failed swaybar endlink, but the handling of the car is compromised.Torn Subframe and Subframe Bushings : Especially prevalent on the E39 Touring. Torn or Worn subframe bushings may lead to subframe failure. Common symptoms of subframe failure are erratic handling and unidentified clunks, squeeks and bangs from the rear of the car. Early detection of a torn or cracked subframe bushing can prevent costly subframe repair and welding.Ripped or Failed Guibo : A torn guibo (Flex Disc) will result in a perceivable 'drive train elasticity.' Acceleration will be preceded with a loud clunk as the guibo bolts bind together.Water Pump Failure : Water pump failure is without a doubt the easiest way to cause extensive and expensive damage to your BMW. The main symptom will be a rapidly overheating motor. What occurs is that the bearing or impeller on the stock pump, breaks, completely disabling the cooling system. If you ever see the temperature gauge on your BMW climb above the 3/4 mark, TURN THE CAR OFF IMMEDIATELY AND CALL A TOW TRUCK!! We can't stress this enough. Failure to catch the overheating motor in time can result in a warped head or even more severe engine damage. We recommend changing out the water pump in six cylinder cars every 60-80k.Cracked Radiator Necks : BMW loves their plastic radiator tanks....Unfortunately...The plastic around the radiator necks become brittle and crack with age, often without warning (see warning above.) Radiators should be thought of as 80-100k mile wear items. Trust us, this is cheap insurance!Thermostats and Housings : 6cyl and e34 V8's. The factory thermostat housing can eventually crack causing cooling system failure. Replacement with an aluminum housing, or replacing with the new composite units every 60k or so will prevent problems. We also recommend replacing the thermostat while the housing is off.Later e39's have electronically controlled MAP cooling thermostats. These will eventually fail and will generally throw a check engine light. When this happens, the engine is running about 10 degrees hotter, and this hurts mileage and will eventually hurt the engine.Fan Clutch Failure : Most fan clutches fail between 80 and 100k miles. They provide the primary cooling for your car, and are easy for us to diagnose.Accessory Belt and Tensioner Failure : Worn tensioners and idler pullies will sound like a squealing noise from the engine bay. Belts should be inspected for cracks regularly. If a belt happens to snap, the cooling system will fail as the water pump will cease to operate. Power steering and the alternator will also fail to work. Again, pull over and shut the car off immediately should you suspect a belt failure or see the temperature gauge rise past the 3/4 mark.Leaky valve cover gasket : Prevalent on all BMWs, a burning oil smell could indicate a leaky valve cover gasket. If the condition continues unchecked, oil can seep into the spark plug holes and damage the ignition coils, resulting in costly replacement. Replacement of this inexpensive gasket is a good idea when changing sparkplugs as the coil packs will already be out.O2 Sensor Failure : Poor mileage, poor idle and flat spots in the power curve could be caused by bad O2 sensors. Even if your car isn't throwing a check engine light, they may not be performing optimally. BMW recommends replacing the O2 sensors every 100k miles. Extended high-RPM running/racing and high-performance chips may shorten the replacement cycle.Oil Separator (CCV) : 1996+ 6cyl cars only. If you have a poor idle and periodic Check Engine lights, you may have a bad oil separator. This valve tends to go bad and introduce a vacuum leak which produces the above symptoms and will eventually strand you somewhere. We started seeing these a year ago and we are now repairing more and more cars with this problem. Typical mileage seems to be around 80k. The good news is that the part is only around $75.. the bad news is that the labor runs about 4 hours, depending on the year of the car.Clogged and dirty pollen filterIf the flow of air out of the air conditioning and heater system is not as strong as it used to be, it strongly suggests the pollen micro filter of your car has become dirty and clogged over time. A damp and musky smell can also indicate a dirty filter. This is a service II replacement item.
Here are some great DIY how to guides from our state side friends supplied in the VERY best of E39 Links
. 5 stars
More BMW Tips
Edited by DarkHorse, 29 October 2012 - 10:13 PM.