Peugeot 306 (1993 - 2001) - 97 1.4 Throbbing sound from exhaust

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Wed 20 Jan 2010 14:14
97 1.4 Throbbing sound from exhaust - ah207

This morning when I started the car, I noticed a loud throbbing sound - almost making the whole car shake. Its particularly noticable and loud when the car is stationary - in other words when the engine is just idling. The exhaust seems to chug and throb at the same time - almost as if its 'choking.' Petrol tank is half-full. I took the car to a car-wash two days a go - and used the (dreded) pressure jet wash. Could I have introduced water into the lambda sensor, or the exhaust system ?
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Wed 20 Jan 2010 18:58
97 1.4 Throbbing sound from exhaust - Peter.N.
Sounds as though its down on power on one cylinder, could be that you have some water in the ignition system although I would have thought it would have dried out in two days, could be a faulty coil/plug or could be that the compression is down on one cylinder.
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Thu 21 Jan 2010 17:59
97 1.4 Throbbing sound from exhaust - ah207
Spot on! You were right - the car was indeed down on one cylinder. It took the mechanic barely half a minute to diagnose the problem (after hearing the throbbing noise coming out of the exhaust pipe). So he unplugged each cylinder cap - I could actually hear the sparking! Anyway, 50 Euros (approx 45 UK pounds) was the total damage to get all the cylinders firing back-up again.

Still not entirely sure how this could have happened - I still suspect that the high pressure water from that jet-wash probably knocked something off line.

Starting to feel I can´t keep patching up fixes on this old Peugeot. I´d like to be able to get more mileage out of it (still only has 122K kilometers on the clock) - but small problems keep popping up every couple of months or so. Genuinely considering a part-exchange while its still in running order.
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Thu 21 Jan 2010 22:31
97 1.4 Throbbing sound from exhaust - Peter.N.
It will cost you a lot less to repair rhan a modern car!
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