I have a '99 V70 5 cylinder (non-turbo) with 127,000 miles, automatic transmission. New spark plugs New air filter Belts look good No other issues with vehicle. Original engine and transmission with regular fluid changes At highway speeds, above 65 mph, the car does not run smooth. While the tachome...

99 v70 88k Live in North East Florida, so use the heat only occasionally. Fumes for a few minutes, and is then OK. Just changed the coolant. Can I use som radiator sealant (powedery stuff that comes in a tube?) If i have to change the heater core, does anybody have any instructions on how to change ...