E46 318 Compact. Won't start, bit odd this...

[Megaflow]

So, a mates BMW 318 Compact stalls and then won't restart. So far I have checked or replaced:

1) It's got fuel supply to the fuel rail
2) spark on number 1 cylinder
3) new spark plugs
4) new air filter
5) crank sensor. Rev counter moves on cranking and shows rpm on diagnostics.

Turns over like a good 'un, but just won't go. Diagnostics only shows valve timing errors, which it has had for a while, which I suspect is a failed vanos unit, but he can't afford to replace at the minute.

Anybody got any bright ideas, because I'm clean out of them.

[steve6304]

check the coolant temperature sensor, can give loads of problems.

[S0 What]

If it was a 6 cyl i'd say check/change the cam sensor but not sure if the 4 pot has one ?

[TheEnd]

A 4 cyl with cam sensor/timing errors is usually a jumped tooth on the timing chain.
There's a plastic guide between the two cams that tends to break up, and coupled with an old tensioner, the chain can kick and jump a tooth.

[Megaflow]

TheEnd said:

A 4 cyl with cam sensor/timing errors is usually a jumped tooth on the timing chain.
There's a plastic guide between the two cams that tends to break up, and coupled with an old tensioner, the chain can kick and jump a tooth.

Give that man a cigar... Yep, knackered tensioner caused the timing to slip.