Fault on number two cyl

Been looking back through this thread, and have you conclusively ruled out
the distributor cap?
Did you manage to get an old plug and connect it to the missing cylinder
then start the engine and verify the HT is ok to the plug (by physically
seeing the plug fire?)

Mike

(if you havnt already done so then have a scrape at the contacts inside the
cap to get rid of the burnt stuff -actually oxidized metal-and try again.

 

I don't have another cap to try (which would give a definite diagnosis of
the cap) though I have tried hard to make sure there's no cracks or fault
around the cap - I've used a screwdriver to clean the inside of the cap.
I've swapped plugs around, also checked for a spark with an old plug
touching the engine. I've had a look at this car in the dark to check for
arching across and around the cap. I keep thinking about daft things that I
may have missed or overlooked so your suggestions help me rethink this
through, I would rather change a cap or leads than have to take the head
off. (I don't have the time at present)

Bill

 

Gotta say that although I havnt been loosing any sleep over this, I have
been thinking about it quite a bit.

Just to recap my thinking:

1-cant be a sensor problem, as AFAIK this motor doesnt have any cylinder
specific sensors.

2-we've ruled out a fuel problem because its a single point injection system

3-if its firing a plug touched to the engine then that would tend to rule
out an ignition problem (assuming the plug thats in is clean and correctly
gapped so it too will fire)

4-youve said that it suddenly came on, which would lead me in the direction
of a sudden component failure, rather than something that had developed over
a period of time. (but this is by no means conclusive).


Youve said that the plug was sooty when you removed it originally. if the
motor has been run much since then whats the condition of the new one?
still sooty? how about running the engine from cold for about 30 seconds
then pulling the plug and seing if its wet (with fuel). while we're at it,
is there any indication of a blown head gasket? you know-over pressurising
the coolant, or mayonnaise in the oil filler. (if it was the gasket then
from your description it would only have blown to oil or water, not between
cylinders.

Also, although a compression test has been mentioned, I dont put much faith
in these. all they do is tell you if something is wrong-they arent much use
at telling you what. far better off with a cylinder leak test if you know
someone who can do this. For the benefit of anyone who doesnt know, you
remove the plugs and use a compressor to pump air under pressure into each
cylinder one at a time, making sure that it is first at TDC on compression
stroke. then you listen for escaping air. if it comes out of the
radiator/coolant bottle then head gasket. oil filler usually means worn
rings or bore, but also could be gasket. from the exhaust or air filter is
the relevant valve.

Mike

BTW lack of any sudden noise doesnt always mean anything. when our zafira
snapped its cambelt, bending lots of expensive valves, all my wife said was
"...it just stopped...."