2ltr xsi Missfire

[ru55howe]

Hi everyone,
recently bought an R-reg 306 xsi 2ltr 16v

over the last few days it's developed a missfire / hesitation.

Starting from cold, it idles fine.
pulling away normally, feels fine, but when put under load (any more than part throttle) below 2,000 revs, and instantly it either hesitates and holds in that state (ease off the throttle slightly and it clears, and pulls better) or miss-fires properly and seems to be off on one cylinder

Once you clear 2,000 revs it sometimes clears, and then pulls like a train up through the gearbox

however once the engine get's warm, the miss fire get's worse, and the threshold at which it goes away moves further and further up the rev range,

I had it almost on the limiter at one point and it was still iffy.

If you drive it everywhere just touching the throttle enough to make it accelerate a little, it purrs along nicely.

My gut feeling is that it's electrical, because when it clears (even for a moment) POW! it comes alive and absolutley flies!

The previous owner tells me that the spark plugs arn't very old, and it's had a replacement coil pack previously.
could an injector be at fault?
I've got no engine management light at all illuminated.
trying to find someone with diagnostics to hook it up.


Sorry for the long message.

Russ

[ru55howe]

Bump.
Problems worse now, was running on 2 cylinders today.

[bettyswollocks]

Check your wiring , sounds like a broken wire.

[chopper1192]

Do these beasties have coil packs, like on the XU10J4?

[ru55howe]

i've had various things apart, but it's not gotten any better.

it seems that when i take off one of the rubber bungs that sits onto the spark plug, the car runs as rough as a dog & then my MIL light comes on
I cant pinpoint it to just one cylinder, if i plug them all back in, it runs, just quite choppy, but with no MIL light

looking up into the rubber bung/stem there's a spring inside it, one of those has got a great big kink in it (pictures to follow)

could this be the cause?
if so where can i get a replacement spring?

[ru55howe]

I hopped outside with my digital camera to take a few snaps of my setup,
where i noticed the following misdemeanour's

Coil pack:


but wait a minute....!

Thats not good!


Thats definitely not good:


Dont like the look of that either:

[ru55howe]

Spot the difference:


So in my conclusion I'm in need of a coil pack, judging by the corrosion in picture 008, it's been giving up for a while.