Air vent is only putting out cold air.

BrokenArrows

I have a 99 Nissan Micra.

Last week the air vent suddenly stopped heating up.
Any idea what could have caused it and how can i fix it. Its cold these days. lol.

Voodoomelon

You may have a coolant leak, or air in your cooling system. Have you checked your coolant levels? If they are fine, you may have to have the system bled, much like a radiator. My two cents.

BrokenArrows

Voodoomelon wrote: »

You may have a coolant leak, or air in your cooling system. Have you checked your coolant levels? If they are fine, you may have to have the system bled, much like a radiator. My two cents.

would not have thought it was something to do with coolant. would that not smell strange. havnt noticed any stains under the car but ill check the levels tomorrow.

would it not be something more like a panel that switches between hot and cold breaking?

peasant

yepp ..heater valve could be broken...or just the lever to open/close it.

salad dodger

Could be the head gasket.

Similar happened mrs dodgers astra before xmas, only blowing cold air no matter what the heater settings were.

I'd get it to a garage sooner rather than later. If the head gasket goes it'll ruin the engine. Unfortunatly it's not a cheap fix either.

crosstownk

As already stated - check your coolant level. You shouldn't really drive much further until you are confident that you coolant level is correct. If it is post back and let us know. Then we can take diagnosis to the next level.

BrokenArrows

ill check the coolant tomorrow but ive driven about 500km since this started.

youtheman

1. Is the engine warming up, i.e. is there a temp gauge on the dashboard. If it is not warming up then your thermostat maybe knackered, they always fail-open thus causing excessive cooling via the radiator and hence no heat. If you have no heat from the engine then you have no heat for the duct heater.

2. If there is no temp gauge fitted and you want to confirm that the thermostat is at fault do the following : cover the radiator with carbboard or the like, and then take the car for a SHORT drive. Put the cabin heater onto hot and see if you get warm air out. After a few miles stop and remove the cardboards over the radiator, you don't want todrive too far as you would eventually damage your engine.

BrokenArrows

Coolant is fine. Full to the brim.

Engine is heating up but not overheating. The gauge rises about 50% of the way up the meter maintains it there. It might get a little higher on long journeys but not much.

Barr

exact same thing happened on my friends fiesta - turned out to be the heater control valve

Armadillo

I drove a 00 micra recently that blew hot air to the windscreen and side and lower vents but blew cold air through the vents located above the radio in the middle of the dashboard without adjusting the temp controller - very strange...

fryup

it could be an air lock in your cooling system, which may be preventing warm coolant getting to the heater core

try empyting the cooling system and then flush it out by running water through it using a garden hose