compression test advice

[Deefadog]

Hi all i just bought a compression tester from Halfords, now I need to get the car to running temp and then disconect the coil, how do I disconnect the coil? I don't know where it is i am really stupid Is it where the middle ht lead comes out of?

A pic would be great

Also when I do the readings what should they be?

[16v Matt]

Yes mate, its the middle one. Make sure the disconnected lead is'nt touching anything or ANYONE when you crank it. Not sure what's good but my valver was 10bar in all cylinders. Would be interested to see what you get. Its important that all the cylinders have a simlar compression too.  
Cheers,
Matt.

[Deefadog]

Cheers, so it's the middle ht lead from the coil I disconnect, yes and rap some insulating tape around it to keep everything safe? any more tips when doing this?

[16v Matt]

You might want to wait for expert  But thats all i did. Just Take one spark plug out at a time screw the compression tester in & crank the car for a few seconds take the reading, put the spark plug back & move on to the next one.

[16v Matt]

Oh & i think there is wet & dry compression tests. I'm sure someone will tell me if i'm wrong, but the above is a dry test?  Not sure what the wet test tells you, someone here will defo know. Cheers.

[Deefadog]

Thanks Matt

[mk1]

I would not leave the coil lead open circuit as this will cause a massive voltage build up and can damage the ign amplifier . Recommend disconnecting the low tension wires to the coil, and when cranking the engine hold the throttle open to give the most accurate reading.
Steve.

[Deefadog]

Thanks

Is this the coil?:



And if it is I have a spade free as you can see, should I have something connected here?


MK1 -  When you say "Recommend disconnecting the low tension wires to the coil"

Are these the other spade connector to the coil?

[mk1]

Yup, thats the coil. (nice picture )
Spare terminal on the coil is OK, disconnect either side and it will be OK.
Steve.

[Deefadog]

Cheers mate, funny thing is when I came home today and let my car run on idell for a few minutes(as I always do, since ot started smoking) it did not smoke, but my mileometer stoped working, but rev counter was fine, if it aint one thing it's another

Happy days