Misfiring Granny

[chriswarren]

Hi All,

Have had a 2.0i DOHC Granada for the last 2 years (new top end last year), and it's now driving me mad.

The symptoms:

- on medium to hard acceleration, anything below around 2000rpm, it starts firing on 3 (perfectly regular misfire) and it just won't accelerate until I ease off the throttle
- this happens intermittently, sometimes I can go without noticing it for days, other times it's there pretty much all the time
- have changed the coil, distributor cap, leads and plugs, idle control valve
- if I blip the throttle hard and look at the leads at night, if it misfires, I can see arcing along some of the leads in time with the misfire

Is any arcing definitely a sign of bad/inefficient leads, or can another electrical fault inevitably cause even the best leads to show some arcing?

If anyone has any other ideas what may be wrong, I'd be forever grateful to hear them.

[chriswarren]

..I should mention that the leads all end up lying beside each other and touching the metallic inlet manifold - not the best arrangement I'd have thought...

[slikk]

If you can see arcing between the leads, they are doing you no good whatsoever.

Reminds me of my GFs car (3.0L V6) - one of the leads had melted through on the exhaust manifold, and the two ends had stuck to it with a gap of about 20mm. The damn thing still ran perfectly !