No hot air through heaters/aircon
- Thread starter jaxk
- Start date
check your water level.
Take the slam panel cover off and look near the expansion tank water cap and you'll find a small cross-headed pastic bolt in the top of the return pipe.
gently unscrew this and slowly add water to the system until bubbles stop coming through the hole you just unbolted.
helps to have the heat set to full and the fan set to a low speed.
you'll either have run low on water, or got air trapped in your heater matrix.
at least, that's my bet and it's the cheapest to check first, as it's totally free
Take the slam panel cover off and look near the expansion tank water cap and you'll find a small cross-headed pastic bolt in the top of the return pipe.
gently unscrew this and slowly add water to the system until bubbles stop coming through the hole you just unbolted.
helps to have the heat set to full and the fan set to a low speed.
you'll either have run low on water, or got air trapped in your heater matrix.
at least, that's my bet and it's the cheapest to check first, as it's totally free
this turned out to be a air bubble in the system.
I took it into BMW and they cleared it and topped up the coolant again and it was fine for a day.
Now I have the coolant light coming on regularly and doing some research through here sounds like it could be escaping through a hairline crack in the tank, or similar.
OK so when it was with BMW they did a pressure test on the coolant system, left it over night and not a single drop in bar on the test.
Would something like a hairline fracture show up or would it only be when the coolants heated up when running the car?
The coolant gauge is showing as minimum (ie float is not floating!) I'm thinking best way to check is put a bit of coolant in go for a drive, let the car heat up and then check around the tank for any moisture escaping ??
I took it into BMW and they cleared it and topped up the coolant again and it was fine for a day.
Now I have the coolant light coming on regularly and doing some research through here sounds like it could be escaping through a hairline crack in the tank, or similar.
OK so when it was with BMW they did a pressure test on the coolant system, left it over night and not a single drop in bar on the test.
Would something like a hairline fracture show up or would it only be when the coolants heated up when running the car?
The coolant gauge is showing as minimum (ie float is not floating!) I'm thinking best way to check is put a bit of coolant in go for a drive, let the car heat up and then check around the tank for any moisture escaping ??
Even a hairline crack should show up in a pressure test run that long, assuming the gauge is reasonably accurate. Still, it is possible for heat to open it up, then upon cooling, the crack pretty much seals up again. If you're adding coolant, it's being lost somewhere regardless what some test says. Try very hard to find out where it's being lost, because if there is no external sign, it's being lost internally, either into the oil or vaporised in the cylinders. Neither of those will be an easy fix.