Hi Everyone. This is my first post. Thanks in advance for your help!
It's a frustrating experience to not be able to figure out why my E36 keeps overheating. Here's the list of changes/checks I've made so far:
1) Removed the thermostat completely.
2) Checked the water pump - it looked fine. It has metal impellers, so I don't think that's the problem. Coolant definitely seems to be circulating.
3) Had a code that the Camshaft Position Sensor was bad, so I replaced that.
4) Removed the Catalytic Converters completely (thought they might be clogged). Now I'm running straight pipes (I live in an area where emissions testing isn't needed anyway).
5) Did a radiator combustion gas test - came up negative.
6) Flushed the radiator and engine block. Seems to be flowing fine.
7) Checked the operation of the auxiliary fan. Works fine on A/C and also kicks in when car is running hot.
8) Used compressed air to clean out the radiator and transmission radiator. The transmission radiator was pretty clogged up - looked like it had been leaking. I will probably replace that.
Here are the symptoms:
1) Starts great. Lots of power when the engine is cold/warming up. No overheating immediately. Can run A/C without any issues.
2) Even without the thermostat, the car slowly approaches, then remains at normal operating temperature for about 15-20 minutes.
3) Starts to heat up after that. Stop-and-go driving definitely speeds up the overheating, but it overheats at a slower rate even on the freeway.
4) Running the cabin heater pulls the temp down immediately, but it still creeps higher after that, especially if I'm still in stop-and-go traffic.
5) No smoke of any kind in the exhaust.
6) Coolant level does not seem to be diminishing.
Could it be that all I need to do is a better job of bleeding the system? I am also going to go ahead and replace the fan clutch also but are there any other possibilities that I should check? Thanks, everyone.