AC Knock?

[Morphyne]

So, I have a 2003 Grand Caravan and it has a slight idle knock. It goes away when you drive it. But when at idle and you turn on the AC the knock becomes horrendous. It's a transverse engine and I have taken off the passenger side wheel and cowl to listen for the knock and I swear its coming from the middle of the engine.


Any thoughts?

 

[Morphyne]

Just found out that it is the main bearing going bad. It knocks when under load. which is why I thought it was an AC knock. Looks like my wife will be walking soon.

 

[verbutani]

Just found out that it is the main bearing going bad. It knocks when under load. which is why I thought it was an AC knock. Looks like my wife will be walking soon.

What do you think caused the main journals to wear so badly that you can hear the crank slapping about?

Did it run low on oil?
Overheat?

 

[Morphyne]

It was leaking oil pretty bad. One time I got in it to drive for morning donuts for the kids and the oil light came on. Long story short, it had half a quart in it.