Tech solutions and real world tips
SQUEAKS AND RATTLES
Q My wife complains that my Citroën AX is noisy and that she has to shout to hold a conversation. Is it just an old car 'thing'?
Ed says
A Old cars are generally not so quiet as modern ones, but an excessively noisy classic may have something wrong somewhere. If the engine is loud when revved in neutral, look for missing or ruined sound insulation felt at the bulkhead, front footwells and, for RWD, transmission tunnel. Look for holes where a rubber blanking plug has fallen out or a gaiter has rotted away. If the sound is very intense at speed, accelerate, decelerate and drop the car into neutral to see whether it's related to the engine, transmission or simply the speed of the vehicle. It might take quite a bit of trial and error, but here are some common culprits.
If the noise is related to speed alone: old tyres can become noisy, and some tread patterns are not quiet to begin with. Propshaft joints make the whole cabin boom or shudder at speed. Wheel bearings drone, rumble or scrape through the whole body shell. If the car's very loud under power, make sure the carburettor, ignition and valves are all set up correctly – including the ignition advance and the camshaft timing. An engine that's out of tune has to work extra hard and is noisy and boomy.
Hardened, collapsed or bodged engine and gearbox mountings can create tiring boom and vibration. Some exhaust systems are not great at noise suppression – but often a booming exhaust is a symptom of an off-tune engine.
Road rumble is best isolated by finding an empty stretch of ultra smooth asphalt. If the car's quiet on this, then suspect missing soundproofing or worn/ hardened suspension and (particularly) damper bushes. If still noisy at speed, suspect a wheel bearing or tyres. Slow right down: if you now feel a regular vibration, then one
