Hello to all.
I really need help, since I can't think of anything left

In my 1990 Fiat Uno 60 SX (1108 engine), the cylinder 2 doesn't fire.
- I replaced all spark plugs - still no difference;
- I replaced distributor cap and rotor - still no diference;
- I measured the resistance in spark plug wires and they are ok. Plus, I switch the spark cable wires with the one of cylinder 1: still no difference. Cylinder 2 doesn't fire any way;
- I checked the compression of the 4 cylinders: cylinder 1 shows 14 bar; cylinder 2 shows 13,6 bar; cylinder 3 shows 14,9 bar; cylinder 4 shows 15 bar.
Even though cylinder 2 has less compression, it wouldn't be too low for not firing...

What should I do now?


One more thing: it looks to me that when I screw the spark plug to cylinder 2, it turns less than the others. As if the others turned 10 full turns and this one only 5 turns. Could this be the issue? If so, how to solve it?

Thank you all for any help.

Hi, and welcome to FF,

it sounds as if your #2 spark plug is not screwing completely into the cylinder head,
SO the sealing washer is not making contact.. - no seal = limited compression..!!

I suspect you will need to use a tap / chaser / other tool to clean the threads in this damaged area..,
ideally this should be done with the cylinderhead removed.. as the debris from cleaning the thread will fall into the cylinder.

charlie