I seem to have sprung a leak

[A5man]

Hi all, I've got an overheating problem on my Mazda MX5. My gauge went up into the red for the first time yesterday and steam was coming out of the back of the bonnet. I had to add three pints of coolant to top up the radiator today and started her up to see where I thought the steam was coming from. It's hard to tell, but it appears the steam is coming up from the region between the spark plugs and the two hoses at the rear of the engine. Of course it's a devil of a job to get your hands down to detect any wet areas. Any ideas with regards to what's wrong? Many thanks in advance.

[MX-5 Lazza]

Most probably one of the coolant pipes that run run to/from the heater matrix.

[PATTERNPART]

Happened to my sister's car. Dramatic. Replace those hoses with silicone ones which are more resistant to oil.

[snotrag]

Oil leak from Cam sensor, oil degrades the hose till it bursts

[A5man]

Thanks guys. I hoped you'd say it was probably just one of the hoses. I'll let you know the outcome.

[VladD]

As was mentioned, it may have been caused by oil leaking from the cam sensor and corroding the pipe. If that's the case you'd be wise to stop the oil leak too.