ARMERCEDES

My '96 E320 makes a sort of grinding noise sometimes when I start it up. It also sometimes makes this noise under low acceleration. The noise can best be described as the sound a lawnmower makes when it hits some tall grass or some cement. The noise is most appearant when the car is cold. Anyone know what I can do about this?

saturnstyl

Timing chain or camshaft adjuster possibly...

Dan's 1993 190E

The first thing that popped into my head is something I fix every year here in central NY. The heat shields on the catalytic converter and around the exhaust etc. One time I've even had an exhaust clamp rust through with both nuts still in place, I had to have the mechanic rev it up to the suspect RPM while I was under the car on the lift and I could see a slight vibration. This kind of problem is usually evident only at certain RPM ranges until it gets really bad, then it's always there when you accelerate and usually right before the transmission shifts.

Dan

PS if it is the heat shield on the catalytic converter you can take metal hose clamps (a few big ones looped together for at least a 24" circumference) and clamp it tight again. Use a few strategically placed nuts to keep an open space. If it's a heat shield between the muffler and the car and it's too far gone to fix, I usually just remove it. You do want to preserve the catalytic converter shields though, especially the bottom, because it gets hot enough to start a fire if you park on dry leaves or grass.

If you do business with a shop like monroe or midas and you bring it in and tell them you think you've got a loose heat shield, most will fix it for free; especially if you're in for an oil change anyway.

Dan