Hi – I would like some advice on a problem I have started to have on my Astra Mk4. It is a late (2005 plate) 1.6 16V Sport – the one with the Twinport engine. The engine has started momentarily cutting out, quite exciting when it happens in the fast lane of the motorway in rush hour. The problem has the following symptoms:

- The engine cuts out momentarily (the revs dropping by few hundred) and then starts back up
- Problem started occurring 3 weeks ago
- It may only happen once, twice or not at all during my daily 20 minute motorway journey – though does appears to be happening more often
- It may be co-incidence, but the problem usually happens about 5 to 10 minutes into the drive, so may be temperature related
- The EMS light does not flicker and no error codes are reported when I do the ‘pedal test’. (The EMS light just flashes continuously with Accelerator and Brake Pedels depressed).
- The car has done 77,000 miles. The coil pack was replaced a year ago after another misfire - though that one was flagged when the EMS was checked with a diagnostic computer.
- (It may be unrelated but the car has also started having starting problems – on 3 occasions the engine has turned over, started then immediately cut-out. Then started OK the next time).

Any hints gratefully received. Is it worth getting a garage to run a EMS diagnostic - i.e. does the 'pedal test' report all error codes, or does a garage diagnostic computer give more information. If I take it to a garage and no EMS error code is flagged then that could get very expensive without actually solving the problem!!