Sad to share the story but my 2004/Imola/NaturalBrown/Auto ZHP with approx 152K miles is down with engine overheating issue. The car was perfectly fine, no issues. My son took it for a drive, unfortunately the expansion tank cracked resulting in overheating, happened just before he reached home. If you look at my maintenance history, it would be shocking how it happened, everything was refreshed on the car with BMW OEM parts.
Initial diagnosis point to a bad thermostat and faulty Auxiliary Fan Switch.
Replaced the following (BMW OEM parts):
1. Expansion Tank with new cap
2. Water pump
3. Thermostat
4. Auxiliary Fan Switch
5. Fan Clutch
Test drove the car and the temp gauge start going up after about 25-30min. Also did a combustion leak test and the liquid didn't change color.
Based on the observation:
No Exhaust gases in coolant sniffer check
No Loss of coolant with no leak
No Bubbles in the radiator or expansion tank
No Oil in the coolant
No Coolant in the oil
At this point in life I just don't have enough time/energy/resources to go after troubleshooting and spend more money on it, it could possibly be a blown head gasket I am not 100% certain. I would love to see this car restore by a zhp mafia and ready to let it go, DM me a resonable offer. Car is located in dallas, Texas(75033).
Hard to let it go, so much memories attached to this car, some smiles from my son, first time fueling and when it was at a shop for some repairs.
Maintenance History:
Reply With Quote