knocking when idle turned down

[bub2002]

I recently purchased a 1994 eagle talon 1.8l non-turbo front drive (base model I know). After I purchased it, I noticed that the idle was turned up way to high, idling at 1800-2000 rpm. When I turned down the idle, I noticed a knock in the engine. I figure it is a rod or something like that, it has 140000 on it. Does anybody else have any ideas what it could be? Please let me now asap, as I will be rebuilding the engine soon.
thanks

[SJC]

Lifter tick is notorious on these cars, and loud. You can try switching to a thicker oil, and making sure the oil is topped up. Even 1/2 litre low makes a world of difference.

If that is the problem, don't worry about it as it shouldn't cause any harm. In extreme cases there can be "phantom knock" which will retard timing, but I'm not sure if the 420A even had a knock sensor...

There are revised lifters for the 4G63, but again not sure about the 420A...

A wealth of knowledge is at: http://www.dsmtuners.com or http://www.dsmtalk.com

[Moe Man]

diesel?

jk top up the oil man

[kevie88]

Sounds to me like the former owner knew the knock was audible at idle and turned it up to mask the sound.. I think you may have been scammed.

[knucklebuster]

Seeing that the knock wasn't noticeable at higher rpm's, I guess when you give it gas in quick bursts, the knock goes away?Or does it get worse. Maybe the knock goes away when the rpm's are up because the oil pressure is built up. But in short bursts, the oil doesn't have time to build and a rod knock would be more audible. If it actually goes away in short bursts, it may be the mains because as the motor spins faster, it tends to balance itself out (like a gyro) and therefore, less or no knock. This is, of course, assuming it is not something else!