Cutting out

Q I am very concerned about my daughter driving her Ford Puma 1.6. She is a great driver, but the car is stalling five or 10 times per day. It usually happens when braking at a junction or roundabout.

Our local garage can’t find a problem and the mechanic said it didn’t happen when he drove it. The engine management light has been on for about six months, but the mechanic says there are no error codes.

I drove it last night and it was quite nervewracking. I arrived at a roundabout and the car just stalled halfway round and I had to switch off the engine. I nearly ended up in the hospital! Peter

A My first comment would be that if the EML is on, there will be a fault present and this should show up on a diagnostic scanner. It is possible that your garage is using an EOBD system, which may not necessarily pick up the problem, and a dedicated Ford system may be required. I have personally come across Ford codes which have either not shown up when using an EOBD system or have read out incorrectly. There are plenty of scanners that can read the Ford system, so finding an independent with such a system should not be a problem.

There are many components which could cause the failure you and your daughter have experienced, but as the engine does start again once the ignition has been turned off and on again, it is unlikely to be a crank sensor or a coil, which would normally fail and not allow the vehicle to restart until it had cooled down.

I would start by checking the multiplugs on the engine components, particularly the throttle position sensor connection. The throttle body connection and the ECU connections are subject to problems from water ingress and a good check around these areas would be advisable. But I believe the root of the problem will be solved when you can access the fault code or codes which have kept the EML on for the past six months.