Ford Focus Revs Issue

[WinDrop]

Hi All,

Hope all of your cars are running nice and smooth :)

Couple of weeks ago I noticed that when I turn on A/C revs drop down from 900 to 800 (something like that...) which I think is normal...not sure but I think it's normal.

BUT then couple of days ago I noticed that when I turn on my headlights the revs drop as well. They also drop down from around 900 down to 820-800

If in the first case with A/C I think it's normal then with the headlights it's quite odd...Isn't it?

I can also notice that on my cars performance while I'm driving. It's not accelerating as fast and I can feel that the engine is struggling...

When headlights and A/C are turned off cars runs nice and smooth, but as soon as I turn on one of them (or both) on that's it...that's the point where it starts to struggle.

What could be the cause of this?

And is the fact that revs drop down when I turn on A/C normal?

Kind Regards,

Arturs.

[artscot79]

Firstly the idle speed is actually 670 rpm plus or minus 30 rpm so not 900 or 800 this isnt changeable secondly the revs will drop with aircon on im afraid as it saps power from the engine like all engines the more power you demand the harder it works what you describe is perfectly normal do the dash trick and youll find the rpm isnt actually changing it will show on a warm engine 640-730 max switch on the aircon it will dip briefly then fluctuate between those figures add lights its still the same however move to battery voltage it will be 14.4 even with aircon around 14v with aircon and lights all as it should be its simply the demands on the engine and the fact that at idle the car will try to find the lowest emissions altering the idle speed and fueling

[WinDrop]

Firstly the idle speed is actually 670 rpm plus or minus 30 rpm so not 900 or 800 this isnt changeable secondly the revs will drop with aircon on im afraid as it saps power from the engine like all engines the more power you demand the harder it works what you describe is perfectly normal do the dash trick and youll find the rpm isnt actually changing it will show on a warm engine 640-730 max switch on the aircon it will dip briefly then fluctuate between those figures add lights its still the same however move to battery voltage it will be 14.4 even with aircon around 14v with aircon and lights all as it should be its simply the demands on the engine and the fact that at idle the car will try to find the lowest emissions altering the idle speed and fueling

So you want to say that it's normal that when I turn on headlights my cars engine starts to struggle and starts to wobble (have a feeling that it will stall in a second...)

I would totally agree if a/c would do this but headlights...c'mon...they are only light...they only depend on the battery.

Maybe that could mean that battery is getting old and need to be changed?

Arturs.

[artscot79]

its a 2001 model which is a mk1 by the way and yes it can be normal if the battery has a faulty cell do the dash test and check the rpm on a warm engine and battery charging voltage then post up the results and we will see if the cars behaving normally it mnay be an idle control valve issue without the dash trick info its hard to say

[jeebowhite]

Agree'd the battery is certainly a risk, but on the age, it could be a faulty alternator.

Best thing to do is get it checked by SEVERAL garages (especially kwik fit) get multiple opinions on the battery and charging systems. I did this recently and had one garage tried to diddle me, one lied and one gave the same conclusion I did...