Review on Bosch SP0F000042 Mechanical Vacuum Chrome by Chris Moody

Used as a coolant pressure gauge on my 1998 Jeep Wrangler Sport (TJ). Since I can't find a dedicated engine coolant gauge, I decided to give it a try. Using this gauge, I was able to determine that my airtight cap was not holding the correct coolant pressure (0psi all the time). He also noticed a vacuum in the cooling system when the engine was cold (12 inch HG). The failed cap should allow coolant from the expansion tank to flow back into the radiator. It was a very useful sensor. good illumination over the entire perimeter.