engine knock problem

hi, we have a 99 dodge caravan 3.0L with 85k miles. the engine knocks upon start up, i was wondering if this is common, and if its the valvetrain, could it be a bent pushrod or somthing.

also the belt has one less rib bc it gets torn up. after it gets torn up, it works fine. are the pullies misaligned? we had the tensioner pulley replaced and still same problem. thanks

You say that the engine knocks, what does it actually sound like. Is it a mild tic tic tic or a metal to metal knock? One is no problem the other can be very expensive. Is the noise constant or only at start-up? If it goes away and it is a tic then it is probably a lifter that has leaked down, nothing to worry about. If it is a heavy metal knock you could have a rod bearing ready to go out or a rod ready to break. I would bet on the valve lifter!

thanks, it is kinda louder then valvetrain noise, but it does go away after 5 mins. i hope its just a lifter.
thanks

My 94 3.0 does that occasionally too, especially in cold weather. It's done that ever since we bought it in 1997. Someone told me it's common with these motors, but other than the ticking which goes away after a few minutes, the motor runs really good.