 A140 one piston not firing
Hi,
I just bought an A140 S reg (1999), and I've got couple of problems with it.
The engine sounds like running on 3 pistons only (sounds like a diesel engine). First, I changed all the filters, oil and spark plugs, no change. I took it to garage, they hook it up to the computer and gave a faulty air mass sensor (it shows low voltage). The guy who did the test said that in his opinion it's not the sensor but a weak contact or damaged wire.
Today I took out the spark plugs(which were fitted 3 days ago), and one od them it looks brand new (like it never fired), rest of them are slightly black (burned), so I guess one piston is not firing.
Could be a connection between air mass sensor and ignition module??
If anyone had this problem before, or knows what it might be, please advice.
Thank you
Paul | 
