Need help coolant

[Johnbest86]

Guys I need help.

Driving up road van over heated then temp dropped to normal then went up again.
Rac recovered me home.

I’ve changed thermostat, water pump and belt.

Now the heaters only work when stationary and the coolant is pressuring what the hell can I do next

[p2thed]

If you have changed they 3 parts and you are still getting issues with pressure excessive pressure in the coolant system then it maybe an interbal issue with the egr cooler leaking exhaust gas into system or the head gasket has failed. Did you loose coolant or find any leaks after it started to fault ?

[Johnbest86]

No I haven’t lost any coolant, no oil mixing with water, no smoke

[Johnbest86]

No steam coming out, gets up to temp fine, it doesn’t overheat, it bleeds fine.

Heaters work while stationary/idle but soon as I drive it the coolant pushes backwards into the reservoir so then the level in the expansion bottle gets higher and the heaters only come out cold.

[p2thed]

You could try a block /emissions tester on the coolant bottle to confirm no emissions. Ive had a couple of head gaskets go on these, it could be passing into a coolant jacket and wont mix with the oil.