HI there i don't know if anyone can help me. I recently bought a 2015 Transit connect, i had for just over 3 months when i notice the coolant had got really low, so i topped up. Then I noticed a few weeks later that pressure had built up forcing coolant into the expansion tank. When I opened the cap when it was cold, the coolant came gushing outa the expansion tank. I've had it back to ford twice now, they replaced the thermostat. That still didn't cure the pressure build up. So i took it back and got them to do a block test and they also did a system pressure test, and also found no contaminants in the antifreeze, ruling out a blown head gasket. They basically coulndnt find anything wrong. Two days later i was getting the same pressure build up and coolant being forced into the expansion tank. I was wondering if anyone out there has had a similar issue? Would like to hear anyones feedback.

Isnt that why there is an expansion tank? Or am i missing your point.

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