Mike

My engine makes an irregular tapping/clicking/rattling sound when running. Originally I thought it was a heat shield, but after significant searching it seems to be coming from the distributor cap (area). I don't think it's the injectors - I know what they sound like and they are far quieter (believe it or not!) and more regular than the sound I am hearing.

The sound becomes more frequent when I increase engine speed, but seem to diminsish a bit as the engine warms up (though this could be just an impression).

I removed the distributor cap (it was tight) and all seems well underneath. The small shield seemed OK, no undue wear on the rotor or cap, etc. I re-installed everything, and the sound remains.

Any ideas?

Danno

Hold our hand on the distributor cap when it's running and see if you feel any tapping on it from the inside. Make sure both the set-bolts on the distributor rotor and the little plug that holds the rotor to the nose of the cam-gear is tight. They are opposite each other, so you may need to turn the engine over to reach one or the other.

NZ951

I had the exact same thing! I have a pretty lengthy post on it. It may be belt slap also, the old water pump design, or maybe nothing that you can work out like me and eventually just goes away after 3 months.

Peckster

I had it, the plastic shield behind the rotor was loose.

hosrom_951

Also check the timing belt cover. i had a rattling sound coming from th cap area, gone quieter but still there when warm. Found that the cover was not installed properly.

ian kam

bad lifter ? valve?