Car Clinic: What could be causing my BMW not to start?

Q. IT’S INCREASINGLY hard to start my BMW. I’ve replaced the battery and had the fuel line checked. What next?

CP, Ruislip, London

A. Check the battery connections and tighten them with a spanner if necessary. Remove any corrosion with a wire brush; a poor earth connection can result in insufficient voltage at the spark plugs, hence a weaker spark and sluggish starting.

Also, look for leaks around the fuel injectors and get a specialist to check the fuel pressure and fuel pump — a problem with either could mean fuel is not being injected into the cylinders properly.

If none of that helps, the fault could be electrical, requiring a full diagnostic check at your dealership or a BMW specialist.

INSPECTOR GADGET
Dave Pollard has written several Haynes manuals and has tested just about every car-related accessory — read more from Dave here.

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