My car's broken :(

[Gizmo!]

Driving home from Waitrose earlier, it just cut out at 40mph in a straight line. Revs dropped straight to zero, I dunked the clutch, killed the ignition, tried to restart it while rolling, no joy.

Pulled in to a side road. Popped the bonnet: nothing obviously wrong. No dropped cables or pipes, all the fuses look OK, belts still attached, etc. It turns over perfectly, but there's absolutely no 'life' - it's not 'not catching', it's just turning over.

Got a lift home, did some research, went back. Fuel pump relay under the steering column is still firmly attached.

Any ideas?

[Defcon5]

Crank it, then pop a plug off and see if there is any fuel in the pots. Check the sparks whilst you are there

[Gizmo!]

Sparkplug 1 is out... Can't smell any petrol in the cylinders, but can't see any spark either when I turn it over. Are sparks normally visible in daylight?

Assuming that only one thing has gone wrong I'm now suspecting the coil pack...

[NiceCupOfTea]

Immobiliser?

[Gizmo!]

NiceCupOfTea said:

Immobiliser?

Did wonder that, but it wouldn't stop it working while driving along though, surely?

[NiceCupOfTea]

A story for you!

Once, when I was a kid, we were driving up to my grandparents in my dad's old Saab 900 (fairly new car at the time). It was just before New Year, very cold day. Just outside Chester, the car just conked out. Tried bumpstarting it while still moving but nothing. Just turned over once we stopped but no catch.

Waited long hours for the AA on a busy day. He couldn't find any fuel getting through, so all the luggage came out of the boot to check the fuel pump. Nothing wrong.

It turned out that the immobiliser switch the dealer had fitted (in the cubby hole) had been fitted the wrong way round (low gauge wire where the high gauge should have been) and had just burnt out! Bloody dealer!

So, my point is, if the immobiliser fails for any reason, it will just cut the engine.

Do you have the standard Mazda one? (grey square on fob, red LED on top of steering cowling) Does the LED go out when you are trying to start? Or is it aftermarket?

(Mind you, thinking about it, the standard immob on my car doesn't allow the starter motor to turn while it is engaged... )

[Gizmo!]

Totally standard immobiliser as far as I know. The only key I got with it was a standard fob one, I'm now using a replacement after the original one cracked

[Defcon5]

How does your immobiliser work? For example mine will let you start the engine, then cuts out after 5 secs

[Night Runner]

Gizmo! said:

Totally standard immobiliser as far as I know. The only key I got with it was a standard fob one, I'm now using a replacement after the original one cracked

How long ago did you get the replacement key?

See what I'm thinking?

[Gizmo!]

Update

Apparently the cambelt's gone. Oopsy.

Still: non-interference engine, so it should be OK. I'll ask the garage bloke to set the timing to 14 deg BTDC while he's there.

[NiceCupOfTea]

Ah - was it turning over more quickly than normal? Usually a pretty good indicator of no compression...

[Gizmo!]

NiceCupOfTea said:

Ah - was it turning over more quickly than normal? Usually a pretty good indicator of no compression...

Difficult to tell how fast it usually turns over... it usually catches on the first turn anyway

[anonymous-user]

Maybe a daft question but when you say cambelt gone do you mean gone as in snapped, fell off, nowehere to be seen gone?!

[Mr MXT]

yellowbentines said:

Maybe a daft question but when you say cambelt gone do you mean gone as in snapped, fell off, nowehere to be seen gone?!

[Slinky]

I was just reading the opening post and thought ... "cambelt"..

Fortunately, it's a relatively easy fix (as you say, non-interference engine, which is helpful).. Get them to do the water pump while they're at it..

[Gizmo!]

Gone as in broken

Good point on the waterpump. It's at the local (as in: I pushed it there!) backstreet spannerer so I'll mention it.