If you are considering buying a used BMW 6 Series, these are the common problems worth knowing about first. Our garage database tracks 3 known faults for this model, 2 of them rated high severity. Every one below is a repair bill a seller has good reason not to mention.
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Check a BMW 6 Series advert (free) →The BMW 6 Series has 3 known faults in our database across 2 generations, 2 of them rated high severity. The most serious are engine (valve stem seal degradation causing extreme oil consumption and smoking) and engine (the exhaust gas recirculation (EGR) cooler cracks). None of them makes the car a bad buy on its own; the risk is a seller who knows and says nothing.
That is a count of the faults we hold, not a reliability score. Popular cars get written about more, and a newer generation has had less time to show its faults.
No year is a write-off on its own. What matters is which serious faults a given year and engine can have, and whether the car in front of you has had them fixed.
Each one is set out in full below, with the symptoms, the typical mileage and a rough repair cost.
One owner each, in their own words rewritten as a line, and not counted in our risk scoring. A fault joins the list above once a second report or an editorial source backs it.
One owner each, in their own words rewritten as a line, and not counted in our risk scoring. A fault joins the list above once a second report or an editorial source backs it.
Sellers rarely admit these faults outright
We track 7 specific phrases sellers use in adverts to soft-pedal these exact issues. Paste any BMW 6 Series advert and we check it in seconds.
Check an advert now (free) →Recall work is done by the manufacturer, and GOV.UK says you will not usually have to pay for it. These are the 21 DVSA recalls for the 6 Series, newest first. They do not tell you whether this particular car has had the work: for that, put the registration into the free GOV.UK MOT history check, which shows a recall status where the manufacturer shares it, or ask a franchised dealer to check the VIN.
Affected vehicles are already included in Safety Recalls within the markets they have previously resided in. The vehicles may be fitted with a driver and/or passenger airbag/s which if deployed may do so with excessive force causing sharp metal fragments to be released this may cause serious injury which could prove fatal to people in the vicinity.
Put right by: Vehicles will have the affected airbags checked and if necessary replaced.
Affected vehicles may have had a retrofit or conversion of the airbag using a previously recalled airbag variant which if deployed may do so with excessive force causing sharp metal fragments to be released this may cause serious injury possibly fatal to people in the vicinity. The original factory fitment airbag for the vehicle is not affected.
Put right by: Vehicles will have the airbag checked and if necessary replaced.
On affected vehicles overtime the aluminium screws can loosen or break on the adjustable variable camshaft timing (VANOS) units potentially resulting in engine emergency mode being activated.
Put right by: On affected vehicles the eight aluminium screws will be replaced if evidence of faulty screws is found then the VANOS adjustment unit will also be replaced.
A possible degradation of airbag propellant tablets could lead to an over-aggressive combustion in the event the airbag is activated which may cause the inflator body to rupture.
Put right by: On affected vehicles the drivers airbag module will be replaced.
The Exhaust Gas Recirculation cooler may leak over time and cause thermal incident.
Put right by: On the affected vehicles the EGR cooler module will be replaced.
The Exhaust Gas Recirculation (EGR) Module could leak over timeand cause thermal incident.
Put right by: The EGR cooler will be internally inspected with an endoscope and replaced if evidence of leaking is found.
The engine counterbalance shaft bearing bushing into the crankcase may be out of specification
Put right by: Replace the engine of affected vehicles
The branch-off point of the main battery cable may corrode
Put right by: The branch-off point will be checked and reworked appropriately depending on the level of corrosion present
The auxiliary water pump may short circuit causing a thermal incident.
Put right by: The Auxiliary Water Pump of the affected vehicles will be replaced.
The EGR cooler may leakpresenting a fire risk
Put right by: A visual inspection of the EGR cooler to check for leaks and excessive build-up of deposits. The EGR cooler will be replaced on all affected vehicles
The affected vehicles may be equipped with a crankshaft sensor with a software fault.
Put right by: On the affected vehicles the crankshaft sensor will be replaced with a new version.
The affected vehicles may be equipped with a crankshaft sensor with a software fault. The crankshaft sensor cannot process the signal values from the crankshaft transmitter due to an improper firmware level. The firmware does not compensate sufficiently the temperature gradients and the magnetic field strength of the sensor electronic. If the crankshaft sensor cannot process the signal values from the transmitter the Digital Diesel Electronic (DDE) will notice that and change to the emergency operation mode. The emergency mode will be displayed by the check control message engine malfunction. The driver may notice a rough running engine and a reduced driving power (70%). However an engine stalling during driving conditions cannot be excluded.
Put right by: On the affected vehicles the crankshaft sensor will be replaced with a new version.
Due to a fault in the supplier's production process the bolt on the outer side of the seat mechanism on both front seats might not have been fixed properly. In cases where the bolt loosens the customer would be alerted by noise coming from the seat and a noticeable increase in seat clearance/movement. If this is ignored by the customer the securing bolt on the outer side of the seat might come off. If the securing bolt comes off the seat can move backwards in a rear end crash situation.
Put right by: The bolt on the seat mechanism will be checked for excessive clearance and if necessary replaced.
Due to insufficient strength the front universal joint in the rear front universal joint of the rear prop shaft may fail.
Put right by: On affected vehicle replace the universal joint with a modified version
The igniter for the certain airbag modules may not have been correctly manufactured which may affect air bag deployment in the event of a collision.
Put right by: Where necessary replace affected airbag modules.
The screws retaining the variable camshaft timing (VANOS) housing may loosen and under certain circumstances the heads may break off. This can lead to the VANOS leaking oil internally and adversely affect the valve timing adjustment. If found to deviating from targeted data the engine emergency mode will be activated. This will be indicated by a distinct change in engine running. The orange engine management warning lamp and a check message; On vehicles with N51/N52 engines this will appear at ignition recycle on N55 engine it will display immediately.
Put right by: Repalce bolted connection of the VANOS adjustment unit
In individual cases the oil pump may no longer provide the required oil pressure. This may cause severe engine damage. Additionally the occurrence of critical driving situations cannot be ruled out because the oil pressure may drop suddenly while driving. The driver will usually notice a drop in the engine oil pressure due to the check control message ''Low oil Pressure''. It is also possible the engine block will be damaged and as a result engine oil may be lost.
Put right by: The oil pump will be replaced with the correct version.
The positive battery cable routed from the vehicle battery to the engine bay consists of one cable in the luggage compartment and one cable in the underbody. Both cable are connected by a screw connection and covered by a plastic cover. In single cases the plastic cover may have been fitted incorrectly during the vehicle production. Over time an incorrectly fitted cover could cause the screw connections to come loose leading to an increased resistance also humidity may affect the connection and cause high resistance and drop in current. This can lead to the vehicle not starting and in extreme cases the connection could over heat leading to the possibility of a fire in the luggage area.
Put right by: The clips on the battery will be checked the cover replaced and sealed.
Some engines are fitted with an additional water pump for the turbo charger. In some circumstances a crack may develop which then leads to melting of the plug connections and the housing. Further heat development may then lead to scorch damage. In exceptional cases such overheating can lead to smouldering of the water pump. If smouldering occurs an engine compartment fire and vehicle fire cannot be excluded.
Put right by: The water pump will be replaced for a new more robust version.
Due to the ingress of moisture it is possible that a short circuit can occur in the additional coolant pump for the exhaust turbocharger. The driver will be informed of the issue by a warning message on the display in the instrument panel. If not addressed it is possible for further heat build up in the pump which may cause the plug connection and housing to melt and in extreme cases a localised fire in the engine compartment or vehicle.
Put right by: Recall all affected vehicles for the replacement of the additional coolant pump.
The pedestrian safety function in the bonnet may fail to trigger.
Put right by: Replace the pedestrian safety sensor system.
Recall data published by the Driver and Vehicle Standards Agency under the Open Government Licence v3.0. A recall listed here may not apply to every car of this model: the build dates and the registration check are what decide it.
Three stand out. Engine: valve stem seal degradation causing extreme oil consumption and smoking (typically 60000 to 100000 miles). Engine: the exhaust gas recirculation (EGR) cooler cracks (typically 40000 to 100000 miles). Safety: failing airbag (SRS) control units were noted as a problem on the 2004 to 2011 6 Series coupe. The full list above is grouped by generation, with typical mileage and a rough repair cost for each.
No BMW 6 Series year is a write-off, but the F12 / F13 / F06 (2011 to 2018) carries the most serious faults: engine. The E63 / E64 (2004 to 2010) has none rated high severity. Year matters less than whether the specific car has had the known fixes, so check the history for them.
Ask the seller about the engine and safety faults on this page and whether they have been fixed, with invoices. On the test drive watch for thick blue smoke from exhaust after idling for 5+ minutes, loss of coolant with no obvious external leak and airbag warning light stays on after start-up. Read the MOT history for repeat advisories, then paste the advert into the free check, which reads it against all 3 known faults before you travel. Check a BMW 6 Series advert →
The DVSA lists 21 safety recalls for the BMW 6 Series issued between 2011 and 2025. The most recent, from December 2025, is "Takata Driver and/or Passenger Airbag Recall (Global VINs)". Recall work is done by the manufacturer, and GOV.UK says you will not usually have to pay for it. This list is by model, so it cannot tell you whether one particular car has had the work: the free GOV.UK MOT history check shows a recall status from the registration where the manufacturer shares it, and a franchised dealer can check the VIN.
Owners report 35.8 mpg on average across the BMW 6 Series engines with data, about 81% of the official combined figure. The gap between official and real-world economy varies a lot by engine, so the Real MPG page lists every engine and generation separately, from 539 owner submissions. BMW 6 Series Real MPG by engine →
Looking at a BMW 6 Series right now? Check the advert before you go and see it.
If you used to check the Honest John “Good & Bad” section before the site closed in 2026, this page is where that information now lives. We rebuilt the BMW 6 Series owner-report history from the archived Honest John dataset, added our own research, specialist and owner-club sources and DVSA recall data, and we keep it free. Each fault above is badged with its source. The same data feeds our free advert check, which reads a listing against every known fault for the exact engine and year.
CarAdCheck is not affiliated with Honest John or Volkswagen Financial Services. What happened to Honest John, and where each feature lives now.
Knowing what a BMW 6 Series goes wrong with is half of it. The rest is reading the advert and checking the car's history before you hand any money over.