you may recall I have had a few issues with my focus titanium for the past 12 months (link to one issue below) since ford replaced with a new engine almost a year to the day!
anyway it went into fords a couple of weeks ago for a service and they did a PCM software update & air filter change for me.
Starting issue seems to have gone away touch wood, however have noticed an intermittent problem happening with the car since the service!
[b]Revs drop and Battery light flash upon harsh braking[/b][u][/u]
Noticed a few days after the service that When I brake hard, clutch down (not emergency stop btw) but harsh braking coming up to turn into a junction for example I have noticed my revs drop really low and battery light flashes on as if about to die but then engine seems to correct itself, however it cut out on me last night as I braked to drive over a speed hump - restarted okay mind (had headlights on heated rear screen prior to it stalling).
doesnt always cut out or flash battery light on - say for instance I am driving along in traffic and slowing while approaching traffic lights the engine drops to normal revs upon stopping.
Well i've phoned ford today and re-booked it in for them to check - my initial thoughts are it could be air leak or something to do with the air filter change they did, have they possibly disturbed something near to the air filter housing??
[b]Idle Valve Fault Check[/b][u][/u]
I also thought Idle valve may be the problem but I read somewhere that you could do a check with your car to eliminate a faulty ICV so I have just been out to car to do this.
1. Warmed car up to normal temp
2. switched all electrics on (heated rear / front screens, headlamps, air con, wipers)
3. Rev up to 3000RPM and held for few seconds.
4. Let go of pedal and watched revs drop slowly to normal idle revs
I read that if the revs drop straight to about 600RPM upon doing the above then the valve is faulty so hopefully I have eliminated it being the idle valve.
I couldnt really look to see around the air filter housing as too dark but will check at weekend.
[b]Dash Diagnostics Trick[/b][u][/u]
I put car into diagnostics dash trick mode so I could have a look at a few other things (i.e. digital revs and battery voltage). When I did the dash trick the gauge sweep happended and the speedo needle got stuck on 80mph and wouldnt move, I turned ignition off and turned on again but needle still stayed at 80mph. turned off again and did the dash trick again got to the gauge sweep mode and needle moved back to 0. Not sure if this could have been a sign of anything wrong or not?
I also checked the battery voltage, this was reading 13.9v whilst car idling with just headlights on.
I switched air con on, heated front & rear screens, fog lights and wipers and battery level dropped and fluctuated to between 11.9v - 12.0v - presume this is because of the electrical load on it and the fact I was stationary so alternator was not turning as fast! Battery returned to 13.9 v when turning above load off.
Hopefully I will get sorted on my next visit to fords next week as I have had about enough of niggly little problems with this car.
Link to another post of mine below