Poor Heaters

[mr impact]

Hi guys, need some ideas on the heating system on my is200 sport please.

Basically the heaters only get 'luke warm' even on a long drive. Its not like they are stone cold, it warms up abit, just nowhere near as hot as they should be. I have drained the radiator and re-filled with antifreeze, also tried to wash through the heater matrix. It started to flush through some 'muddy' water, then it ran clear. We tried to back fill the matrix in a bid to stop any air locks, then ran the engine to top up the rad which expelled a few air bubbles.But the heaters are the same as before.

The radiator holds water level ok, there are no leaks and the car runs ok with no over heating or anything. All the pipes get hot, including both pipes in the matrix. The only thing I have noticed is the bottom radiator pipe dosnt get warm until you have gone for a pretty long drive.

So could it be the thermostat or water pump not working properly?

I also hear a water 'gurgling' noise from the matrix when you go round corners sometimes, like there is still air in the system.

Any tips on a better way to bleed the air out of the system?

All the interior vents blow the same temp air, as Ive been told sometimes the passenger side can be warmer than the drivers side, but mine are all the same. Only just warm, no where near as hot as they should be.

Any help would be great.

Nick.

[clifton 94]

Hi if you let the car just run and the fan kicks in does the heater get hotter . Also when you turn the fan on does the heater loose the heat after a little while

[mr impact]

I actually havent heard the engine fan kick in at all to be honest. Even leaving on tick over after a drive. The only fans that seem to kick in are the aircon fans when you switch that on. If you rev the engine it seems to get abit warmer then goes back to normal when you go back to idle.

Surely if it was thermostat, the pipes into the matrix wouldnt get hot? And if it was water pump, the engine would run hot?

[clifton 94]

What does the temp gauge read when driving

[ChrisIS200SportTTE]

If the bottom radiator hose doesn't get hot then the thermostat isn't opening

[ChrisIS200SportTTE]

The temp gauge should be at 9 o clock. And it should never fluctuate. It should gradually rise until it hits 9 o clock then stay at 9 o clock. Does it take a very long time to get to 9 o clock? Or if it doesn't get there it's def the thermostat

[mr impact]

It seems to get to half way on the temp gauge as normal and never gets any higher. I even took the car on a local drift track at the weekend and even with some thrashing it only went a little over half which is usual for any drift car really. The bottom rad pipe does get warm eventually, just seems to take longer than it should.

It seems like there is air in the system, but just doing the usual thing of running the engine to temp with the rad cap off dosnt seem to do the trick for some reason.

[shortfuse]

are both the heater feed pipes in the engine compartment hot?.

if so your heater matrix needs changing.

i had the same problem tried everything to no avail.

but when i changed my matrix this solved my problem

i now have a very warm car interior

[mr impact]

Yeah both pipes to the matrix get hot, so I guess its matrix change time then! Although I dont have any water on the inside the cabin. When one of my dads cars heater matrix went, it soaked the carpets on the inside. I do know someone who is stripping an is200 for racing so I'll see if he can get the matrix out of his.

Thanks for the advice.

[shortfuse]

its not the fact that its leaking, just totally gunged up

the radiator specialist i used took two hours of constant flushing

along with air pressure to un block it