BMW 5 Series Spark Plugs: Intervals, Fitment & Warning Signs

On the 5 Series, a confirmed technical bulletin genuinely addresses certain engines failing to restart after a cold start, caused by a specific spark plug part combined with software — since superseded twice.

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OEM Part Number: confirm via engine code — aftermarket NGK 97506 / Bosch 0 242 145 541 and 0 242 145 515

Accuracy note: Covers the BMW 5 Series (F10 2010-2017) as listed in the UK aftermarket catalogues. Spark plugs are engine-specific — thread size (M12 vs M14), reach, heat range, electrode type (copper, platinum, iridium) and gap all change between engines in the same car, and the catalogue listings below cover every petrol engine in the generation without always saying which plug fits which. Match the plug to your engine code (on the V5C or the engine cover), fit a full set of the same type, and use the maker's gap and torque. Genuine numbers are shown only where a listing quotes one.

Petrol engines in this generation	520i 163, 170 and 184 HP; 523i 204 and 211 HP; 528i 218, 243, 245 and 258 HP; 530i 258 and 272 HP; 535i 305, 306 and 326 HP; 550i 405 to 452 HP; M5 560 to 600 HP; ActiveHybrid 340 HP
Spark plugs (aftermarket)	NGK 97506 (iridium, 14 mm Bi-Hex, M12x1.25); NGK 91874 (iridium, gap 0.8 mm, M12x1.25); NGK 95712 (platinum, 16 mm, M14x1.25); Bosch 0 242 145 541 and 0 242 145 515 (gap 0.8 mm, M12x1.25); Bosch 0 242 236 653 (gap 1.0 mm, M14x1.25); Champion OE242 and OE243 (platinum, gap 0.8 mm, M12x1.25); Denso SXB24HCF-D7 (iridium centre, platinum earth, M12x1.25); Denso IKH20TT (iridium, M14x1.25)
Genuine (OE) numbers quoted	Denso SXB24HCF-D7 quotes OE 12 12 0 050 948
Fitment notes	The main family is 14 mm hex, M12x1.25, used on most of the turbo petrol engines; a smaller group of 16 mm, M14x1.25 plugs (NGK 95712, Beru Z235, Denso IKH20TT, several Bosch and Hella) is listed too, so the engine decides

BMW 5 Series Spark Plugs: A Cheap Part That Causes Expensive-Feeling Problems

On the BMW 5 Series, there's rarely a clear signal when spark plugs wear out — just a rougher idle, marginally less pep off the line — vague enough to get pinned on other engine issues. Since the part costs so little, it's also one of the easiest things to keep putting off.

Before you buy: plug type and gap specification vary by engine size and generation. Always confirm against your VIN before ordering.

BMW 5 Series Spark Plugs: What They Do

On the BMW 5 Series, combustion efficiency, fuel economy and smooth running all trace back to spark plug condition, since these are what ignite the compressed fuel-air mixture in each cylinder. Petrol engines depend on them entirely — diesels skip spark plugs altogether, igniting fuel through compression instead.

BMW 5 Series Spark Plugs: Generations, Engines & Spark Plug Count

Diesel variants (520d, 525d, 530d, 540d and similar)	Not applicable — diesel engines use compression ignition and have no spark plugs at all
Petrol four-cylinder (520i, 530i, 530e plug-in hybrid)	4 spark plugs — one per cylinder
Petrol six-cylinder (540i)	6 spark plugs — a genuinely different engine family (BMW's inline-six B58) from the four-cylinder units, not a bored-out version of the same engine
Petrol V8 (M550i, M5, M5 Competition)	8 spark plugs — BMW's twin-turbo V8 (N63/S63 family); confirm your exact engine code before ordering, since M-division tuning of this engine uses different plug specifications from the standard M550i

BMW 5 Series Spark Plugs: Watch: Replacing It

🎬 Watch: BMW How To Replace Spark Plugs N55 F10, F01, F02 535i 2010 - 2016

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F10 535i N55

BMW 5 Series Spark Plugs reference plate

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Confirmed: A Genuine Technical Bulletin Worth Knowing About — BMW 5 Series Spark Plugs

If the engine has turned over but failed to actually start on a repeated cold-start attempt, this is genuinely worth knowing on models fitted with certain petrol engines: a confirmed technical bulletin identifies exactly this fault, where the car may start normally on the first attempt, but then fail to start if switched off immediately and tried again shortly after. The cause was identified as unfavourable engine management software combined with the original spark plug part, since superseded twice with revised versions.

A genuinely useful diagnostic technique worth trying: swapping a suspect coil to a different cylinder is a direct way to confirm whether a misfire is genuinely coil-related — if the misfire follows the coil, this confirms it; if it stays on the original cylinder, the cause is more likely the plug itself.

It's also genuinely worth knowing that coil packs have been documented failing even on cars with genuinely low mileage, worth knowing that mileage alone isn't a reliable indicator of whether this specific component needs replacing.

BMW 5 Series Spark Plugs: Warning Signs, DIY Difficulty & Aftermarket Advice

These are the same regardless of make or model — see our full Spark Plugs Guide for symptoms of worn plugs, why matching your exact plug specification matters, and trusted brands to buy from.

More BMW Spark Plugs

The same part, covered across other BMW models.