Low idle when internal fans on

[xpeterpx]

Now I would expect there to be a lower ilde as there is extra load on the battery but its to the point where the car nearly wants to cut out when the internal fans are on? (revs dip every few seconds to be exact)

I'm thinking battery needs replacing soon here, but anyone confirm this or any other ideas appreciated 

Thanks as usual

Pete

[ayup]

have you checked the voltages with engine not running and running with/without load ie lights , radio , heater and all the other electricals on

[xpeterpx]

I will do . Just thought someone may have experienced this already this winter. Looks like its pointing to the battery?

[Lenny]

2 hours ago, xpeterpx said:

Now I would expect there to be a lower ilde as there is extra load on the battery but its to the point where the car nearly wants to cut out when the internal fans are on? (revs dip every few seconds to be exact)

I'm thinking battery needs replacing soon here, but anyone confirm this or any other ideas appreciated 

Thanks as usual

Pete

If replacing the battery I highly recommend a Bosch S4 or Bosch S5 there available in a range of sizes to match the vehicles amperage.

The cold weather zaps the life out of old batteries,

If your looking to improve the overall electral system then Fitting a genuine "Pivot Raizon" voltage stabilizer will also help regulate voltage for demand acting like a resivour of power capable of cushioning demands which relieves strain on battery to become a constant steady flow. 

Loads of cheap replicas on eBay but they have negative effect you can source geuine here: http://pivotjp.com/product/vs-m/vs-m-e.html 

Another improvement is called "The big three upgrade" 

Quite cheap really; involves some 0AWG cable and crimp ring terminals.

this helps regulate current in the complete electrical system.

 

[ayup]

buy a digital multitester , spend 30 seconds learning how they work and how to read them , they are simple

[Tdci-Peter]

4 hours ago, xpeterpx said:

a lower ilde as there is extra load on the battery but its to the point where the car nearly wants to cut out when the internal fans are on? (revs dip every few seconds to be exact)

The electrical load on the alternator should not really affect the idle speed. These engines have the idle speed continuously regulated by the pcm (aka ECU). If anything, the idle may increase a bit under heavy load electrical, to ensure it can meet it. There may be a slight change when a load goes on or off, but it should very quickly recover.

If the idle is varying, then I suspect a fault. In some Mk1 Foci, there is an idle control valve that can get a bit sticky. In all Mk2 Foci, the idle is controlled by the throttle body (petrol), or direct control of the injectors (diesel).

If the battery was really dodgy, or there was a bad connection to it, perhaps the engine or body earth, then maybe that could upset the pcm and cause unsteady idle. The voltmeter (see pete above) would be a good test for this.

If not that, then you ought to specify engine type, and Mk1 / Mk2 (2004 could be either, I believe).

[Tom1994]

I had what sounds like a similar problem to you, although on my 2013 ST.  As silly as it seems the problem disappeared when the garage I bought it off put ran some engine cleaner through it and advised that I fill up with high octane fuel just this once to see if it continued.  It has seemed to solve the issue and I now try and use Shell V Power whenever I can, or as good of an alternative as I can get.  

My revs always seemed to drop after a long motorway journey and then coming off the slip road and having to wait at the lights before setting off again.  It was a suspected sticking throttle body but we never found out as the problem went away. If this sounds similar to your problem it might be worth giving it a go, expect it would be a lot cheaper than having a garage take a look at it.

[spurswes]

15 minutes ago, Tom1994 said:

I had what sounds like a similar problem to you, although on my 2013 ST.  As silly as it seems the problem disappeared when the garage I bought it off put ran some engine cleaner through it and advised that I fill up with high octane fuel just this once to see if it continued.  It has seemed to solve the issue and I now try and use Shell V Power whenever I can, or as good of an alternative as I can get.  

My revs always seemed to drop after a long motorway journey and then coming off the slip road and having to wait at the lights before setting off again.  It was a suspected sticking throttle body but we never found out as the problem went away. If this sounds similar to your problem it might be worth giving it a go, expect it would be a lot cheaper than having a garage take a look at it.

I suppose BP ultimate (higher price) is just as good as the Shell one ? 

[artscot79]

it's worth noting that higher load creates higher emissions and the focus is meant to find the lowest least emission emitting idling so it will idle as low as is possible

[drsdriver]

9 hours ago, spurswes said:

I suppose BP ultimate (higher price) is just as good as the shell one ? 

Yes, BP Ultimate just as good as Shell V Power. 

[TomsFocus]

One of my mates basically lives in the petrol station due to owning many thirsty cars lol, he reckons BP Ultimate is best for mpg compared to VPower or Momentum99.

[spurswes]

2 hours ago, TomsFocus said:

One of my mates basically lives in the petrol station due to owning many thirsty cars lol, he reckons BP Ultimate is best for mpg compared to VPower or Momentum99.

Lol,I thought they're wouldn't be much difference but just wanted to double check. Cheers mate

[Tom1994]

14 hours ago, spurswes said:

I suppose BP ultimate (higher price) is just as good as the shell one ? 

Yeah, probably better as its "Ford recommended" but there isn't one near me so I have the next best thing