Error code cylinder 4 misfire on 01 Opel Astra 1.4L

Calahonda52

Have an OBD Link which gives the above when the engine light comes on.
I have had the sparking coil replaced which failed to solve the problem.

After I clear the code, it comes back on after about 3 or 4 kms and the performance suffers, up to cutting out.
Engine temp is normal
The garage which replaced the sparking coil says its difficult one to diagnose so I wonder is it worth running the OBD analysis software on the cell phone while the car is driving and try interpret the reports?

Any other ideas would be appreciated.
Thanks as always.

GerryDerpy

Current ramp the injector
Check that spark plug is sparking

Is it coil on plug or coil pack?

Calahonda52

GerryDerpy wrote: »

Current ramp the injector
Check that spark plug is sparking

Is it coil on plug or coil pack?

Thanks, its a coil pack which they replaced the first time, for about 170 euro, am only interested in getting it fixed as opposed to any "row" with the garage.:)

It got new plugs in November.

Will ask them about current ramping the injector
Thanks.

Calahonda52

So back again.
Issue is recurring, but very intermittent, can go 4-6 weeks with mixed driving ( town/motorway) and the light stays off.

Got the OBC kit to run with the phone and its Error 504.

When it happens, the light begins to flash at 60km/h and the car loses power above 60 but is fine below.
The light then stays on and is fine bowl 60 km/h
clearing the error code solves the power loss problem and it might be fine for another few weeks.

So am wondering if clearing the code will damage the the car or mask some underlying problem with cylinder 4.
Thanks as always