Scottie_

Hi folks, Need some assistance. (F reg 2.9 XR4X4)

I am having an intermittant problem with main beam, Flick the swith once and side light come on, Flick it up to main beam and they go very dim. Next time i try they work fine. I have checked wiring around the headlights and fuses but everything looks fine. I have also changed the switch itself with a known working one so can rule that out.
Familiar to anyone?

I also have rear dicso lights but think that is just a bad earth?

At the same time this happened the car also started to idle badly, Every 30 seconds or so dropping a cylinder and sounding like it is about to cut out but instead it picks it self up as if you had given the throttle a blip. When driving it seems fine. Any ideas?

Could all these be connected?

Any help appreciated.

Cheers

dojj

iTrader: (3)

rear lights is a bad earth, you may need to change the whole unit as well as clean the contacts on the plug

the hunting you get is the idle speed control valv, found on the drivers side of the inlet manifold butterfly/throttle housing
clean it out over night by laying it in a container full of petrol and see if it solves the problem

not too sure abou tthe headlights though, alternator charging properly?

Scottie_

Hi Dojj, Thanks for reply.

Rear lights i am not too concerned about, know that is an easy fix, Earth straight to the light unit. Headlights are the issue, Its a bit strange as i hadn`t linked it myself, Spoke to an autospark and he asked if it ever dropped a cylinder and is thinks that they are are realated somehow?
He is coming to look at it tomorrow but would like any input.
Its very strange that sometimes they will work fine and then for no reason they dont, Have tested with engine running and off but but it makes no difference, With no vibration or anything going through the car it still has the intermittenent problem.

Quite stuck here, Could it be as simple as a main earth? eg Gearbox. Never thought to check earlier when i was at the car?

tabetha

It is designed by ford to do this, ie be a pain in the rs!!
If you look at the earth connection in the headlight plug, not the bulb plug you may even see it all green and rotten, the cable builds a massive resistance, earth is brown btw.
The front light problem is a bad earth also, when you switch to main beam and the inner lights come on along with the outer main beams, it draws more current that the earth side can supply, so it searches for an earth path, this it finds through bulbs that are already connected to earth, hence the problem.
If you want the best lights, put in seperate relays, 2 each side one for dip and 1 for main beam, these can be hidden inside the headlight casing, that's what I do, have done on me xr4i and me sapphy, makes a massive improvement, renewing the earth at the same time direct from the battery, then put in philips extreme H4, you'll think it's hid, the difference is that dramatic, done this on me dad 4i also.
If not wanting to do it as best you can, then simply run a wire from the battery earth to the inner headlight earth connection point, that you can see when you remove the little cover for bulb replacement, fine to elave the other earth as it is, as this conenction goes to both main/dip bulb and the inner bulb.
The best cure for the disco lights is to hard solder the wires direct to the bulb holder tracks, I have done this all the time, use a dremel etc to drill a small hole say 3mm in each light track, then solder the wires in after tinning the wires, the hole has the advantage that it is a clean edge and so the solder will take 100% perfect, then for the earth(brown) on each light panel simply solder a wire onto here and extend it to the light mounting bolt in the boot, after rubbing down to bare metal, put a ring terminal on the end, bolt up, then cover with coppaslip or similar, you will 100% not have any more disco lights.
I also do the brake light fog light mod at the same time, simply place a rectifier diode across the brake and fog light tracks, this will light the fogs under braking, but the fogs will still light up from the switch seperately, without lighting the brakes, the rectifier diode is a one way electrical valve, so current flows from brake to fog but not the other way around.
tabetha

Scottie_

Thanks for all the help, All sorted now and got the MOT. Still need to solder the connections on to hopefully never have disco lights again. Idle control valve still needs looked at but will get to it. Thanks again.