I have 2 general problems.

- When I start my 190E and turn on the air conditioning, there comes a very loud e...e...e...e... noise from the front. The noise stop after I drive for half a kilometer. If I stop and engine and start immediately, the noise does not happen. It seems that the noise only happens after the car has stopped for a few hours and only when I turn on the air conditioning.

- I replace the tires, but with a incorrect thickness. 60->65. Will this affect the speedometer to produce the incorrect reading? or the difference is negligible?

Thank you.

The 65 represents the ratio of sidewall height to the width of the tire. So if you have 255/65 it means the sidewall height is 0.65 x 255mm which is 190mm. Add this to the rim size of 15 or 16 inches (why can't we just use metric?) and get the circumference from 2 x 22/7 x radius. Also, these measurements aren't exact. Different tires with the same "size" will have different measurements.

Kuan

The noise when your A/C is turned on is likely the belt slipping. Either the tension is too low, or the belt surface is glazed.

If the tires are 195's, the '60' profile will cause your speedo to read higher than actual speed, by a small amount. A falsely high vehicle mileage will accrue on the odometer, as well.

Steve