mk1zetec

Hello to all.

I am newbie, though have looked on this site many times as i know there are a lot of knowledgable people on here.

I now find myself in a position where i need a bit of guidance so i thought i would try on here 1st.

Came back today from a weeks holiday and decided to take car out. Found the battery was flat so jump started it.
Not unusual as the car does not like to sit for very long and this has happened a few times in the 3 years i have had the RS.
It started easily and i left it ticking over for a while as i put the leads away. Started driving the car and noticed the battery light was on, decided to turn round and go home as i did not think the car would restart if i pulled over to have a look.
Then the car started to run rough so i limped back home, only 400 yards or so.
Got car on the drive and checked everything over, all looked ok. Started the car up again, battery light had gone out. Though the car was still missing, pulled each lead and found that it wasn't firing on No2. So i changed plug, no difference. Changed lead, no difference. Changed coilpack, it ran smooth as silk . Took car out for drive, got about as far as before and it began to run rough again .

Now i have two focus's (mine and the wifes, who's car i nicked the bits off to do the tests) with coilpacks that are useless on No2!

If anyone has an idea as to what might cause this i would be grateful to get to the root of the problem.

Also puzzlingly, although the car ran for very short periods of time, not enough to put any real charge into the battery. It started every time i needed it to. At least 8 times with no further need to jump it!

davecosworth

check the charge rate on the alternator as it could be the voltage regulator, or it could just be one of those things about the to coil packs i had two go on my focus and it wasnt even six months old

SafeChav

I know there was a certain type of coil pack (on the mondeos i believe) that were prone to break down on one specific connection.

Sounds like it has a few issues though mate, might be cost effective to get it on the diagnostics machine being such a new car......?

tabetha

Worth trying your original coilpack on your other halfs car to see if it runs OK.
Coilpacks are only double sided coils ie two coils in one each feeding a pair of cylinders, so hard to see how it can feed one and not the other one on it's pair, unless as suggested there is a connection problem INSIDE COILPACK, very unlikely as a known good one does the same.
It sounds as though your car has developed a fault like lack of compression due to sticky valve follower ?
The connections from loom to coil must be ok otherwise you would lose two cylinders if eithe one half stopped working ok.
You coulkd do worse than try both on other halfs car to see if they go OK on it, you say it does not fire on the car but have you put a plug in the end of pulled off lead to check it is firing ?, whilst engine is running on three ?
tabetha

mk1zetec

Thanks for the replys guys.

Have got a bit more info, it would seem it is not the coilpack afterall as i borrowed another coilpack from my brother to get the misses car running.

But her car still wouldn't run on No2 even with a different coilpack. So i nicked a spark plug from one of the RSs unaffected cylinders.

Hey presto, her car now runs fine. This i think shows me that the RS is fouling plugs on cylinder 2, but why after standing for a week doing nothing would it do this?

I have bluefin fitted and the diagnostic shows NO fault codes on the RS, which is weird as the misses car had the management light flashing and showed fault codes following me re fitting her plug which the RS had fouled.

I will try the disconnect the battery reset route and maybe swap a couple of injectors round and see if the problem moves and then fouls a plug on a different cylinder.