My daily driver has developed an odd noise. 2001 Dodge Stratus R/T, 3.0 liter DOHC (non-turbo), 5 speed manual transmission. Oil pressure is steady at 70 psi. Original engine with 196k miles (I bought it with 125k miles). Always maintained, oil was changed 2 weeks ago with a Napa filter and 10w40 High Mileage oil. Here’s the odd part - noise goes away above 1400 RPM. Drives fine with no noises at cruising speeds. Here’s a video at idle and reving it up over 1400.

 

Ouch! That is painful to listen to. When was the timing belt changed last? I think they are supposed to be changed every 60,000 miles.

 

The odd thing is it clears up over 1400 RPM. The timing belt is due, but I took the covers off and it's not flapping around or hitting anything. I'm not familiar with the gears they use to connect the intake & exhaust cams, but I'm thinking the problem is there. I'll pull the valve covers tomorrow and see if something is amiss in there.

 

The noise may be in your valve train. A flat lobe on a camshaft or collapsed lifter can cause similar problems. Something is definitely hammering itself to death.

 

Thats a new one for me. Like mentioned, any idea when the timing belt was last serviced? The timing belt tensioner can make a similar noise, its hydraulic and can fail.

 

And that's what it was.... the timing belt tensioner had lost it's oil, so the spring was being pushed back quickly by the varying forces of the belt as the engine turned. The belt seemed tight sitting still because it was, but turning the engine over with a breaker bar I could watch the tensioner deflect. I installed a new belt//tensioner/water pump yesterday and it's happy once again. Thank you everyone!

 

Did you slap a new belt in there while you were at it?

 

new belt//tensioner/water pump yesterday and it's happy once again.

 

While these engines aren't as robust as the ones from the 1950's through 80's, they are pretty good engines. Belt failure is what ruins a bunch of them. You've probably extended the engine life for quite a bit. It may out last the rest of the car.