hi
i have a 2003 Impreza GX. I keep losing water constantly from the radiator. It runs great 80% of the time but then the rest of time it is sluggish and judders. I can also smell coolant through the heater and if I stop at traffic lights the heater will blow cold until I move off again. I have not had excess smoke out the exhaust if any at all. I have replaced the radiator also the thermostat. Does anybody have any idea what else could be causing these issues ?
Thanks

 

It could be a lot of things, but an easy one to check is to make sure the radiator isn't knackered.
Look at the radiator from the top, the sides should be straight up and down. If they are bowed outwards it's probably time to replace it.

 

I have replaced the radiator with a new one. Also put new clips on the top hose as it did have a slight leak but still the same.

 

possible air lock? These engines are notoriously easy to put an air lock in when re-filling with coolant.

 

The problem is that it is still losing water also but I can't find any leaks. I have ensured that I filled it up to get rid of air bubbles followed a video with a large funnel type thing on the radiator so the air can escape.

 

time for a compression test?

 

Ok I will try that then. Hopefully find out what the problem is. Thanks