Brickers:

First and foremost, a happy holiday to all on the board.

Now, on to business. My 745t's engine has a slight knock, and I'm wondering if someone can tell me all about engine knock.

1) What problems, aside from piston rings/engine age, causes it?

2) What's the best way to go about getting rid of it? Cleaners, lubricants, etc.?

3) Will buying a CO reader and checking the mixture help? I've heard knock can be an indication the engine is running lean... correct?

Recently I did a weak Throttle Body Cleaning. I basically took off the air inlet pipe from the Intercooler and sprayed soem throttle body cleaner on the walls of the visible insides of teh throttle body and sprayed in the edge around the plate to clean out some of the gunk. I'm afraid some overspray may have leaked around the plate and been sucked into the engine when I next ran it. Yeah, I know, should have taken my time, but something came up and I had to hurry.

It may be my mind runing with two coincidental events, or maybe I just didn't notice the very slight knock before, but could they be related? What would the effect of some TB Cleaner being sucked in? Will any efect be mitigated and non-existant over time? The TB Cleaner has to be sucked out or burned off at some point.

Any help on this would be greatly appreciated, I'm trying to silence my engine a bit and am approaching all the little things (outisde piston slap, which I can't help) to fix it up.

Thanks,
Rick