My series 1 will not start. when i turn the key the fuel pump primes. The car wants to start and you can hear little backfires. I have checked spark plugs for spark, I am getting no spark, I have checked coil and i get a reading, Changed HT leads. The only thing that I can think of is the distributor the contacts look slightly worn, as well as the contact on the rotor arm. Can anyone point me in the right direction what could be the problem. Thanks