A140 one piston not firing

[maximallimit]

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

[lofty]

I would have thought it was more likely to be the connection between the ignition module and the offending plug, it's not the coils because each of them serves two plugs,
I feel sure you can get the bits that go to make up the contact see if you can get hold of a module to confirm the problem, the diagnostics should have pointed out the plug that's not firing if that is the case .
feed back would be appreciated

[maximallimit]

Originally Posted by lofty

I would have thought it was more likely to be the connection between the ignition module and the offending plug, it's not the coils because each of them serves two plugs,
I feel sure you can get the bits that go to make up the contact see if you can get hold of a module to confirm the problem, the diagnostics should have pointed out the plug that's not firing if that is the case .
feed back would be appreciated

Thanks Lofty. I read all your website, it's great mate...keep up the good work.

anyway....I checked and cleaned all 4 connections (springs) between ignition module and spark plugs at no avail. Is there a way to open up the ignition module, to check for broken connections or something?

[lofty]

Afraid not, open you wallet yes! £85 ish or e-bay loads of A's being broken you could well pick up a good one there .