325i running issues - a bit of background, help needed

[treble_c]

Hi all, my 325i track slag is a little poorly - i'll start from the top.
When i bought the car a couple of months ago it ran sweet. Pulled good and strong and really was a good drive. Since i've had it home its hardly moved being a track toy and needing prep work doing to it, and having no insurance, MOT etc. all it moves is out of my friends work unit about 40 feet in the morning, then back again in the evening.

In the run up to these probs we had another 325i in for breaking which had about Ԛ£15-20 worth of fuel in, so this was taken out and put into the slag, however, this 325i had been sitting for quite a while so i'm not sure in hindsight if the fuel was off - is that possible???

A couple of days after putting this fuel in the slag developed a misfire - only running on 3 cylinders. After a few more days because of time and work commitments meaning we couldn't look at the prob, we finally let the car warm up, which eventually got the car to run on 5 cylinders, but never 6.

A new rotor arm was purchased and fitted, along with some assured good O.E 2nd hand leads. The rotor arm was fitted along with some good used plugs from the other spare engine we had, dizzy cap cleaned up and the car started to run fine, so the leads were left unchanged. All was well in camp Jamie for about 2 weeks of its 80ft daily travel, when the problem has started again, but will only fire - either cold or warm - on 4 cylinders. The leads were fitted to no avail, and i'm now wondering what it could be, as the 2 cylinders are recieving a spark but not firing.
Could this be the petrol in it being a bit gangster????? I've nearly ran it down to the petrol warning light now so was gonna put some good quality juice in it along with some redex to see if it clears up. I know it probably could do with a good run but its not insured or MOT'd so its kinda out of the question. Has anyone got any ideas????? Haven't whipped the plugs out yet mind as i won't have opportunity to for a few days, just wanted to bounce some ideas around maybe???

Thanks for the patience guys

Jamie

[Karan]

could be fuel shitting up the plugs

[beardymat]

is the water disapearing from the header tank?

could be water in the cylinders preventing them from firing,as the engine warms up the water is displaced and then the cylinder starts to fire.you sometimes get clean plugs on the affected cylinder due to the steam cleaning effect.

[treble_c]

No mate, as said no matter warm or cold the engine refuses to fire on cyl's 3 and 4 always.

[SGP]

lash a strong injector cleaning agent in,listen to the suspect injecters with a screwdriver to your ear,should hear them firing if they work.

[SGP]

Don't suppose you have a spare throttle body by any chance?I'm looking for one.