My Honda Accord LX (1994, 2200cc) is overheating when doing more than 70mph on the Interstate on the flat or when going uphill at 30-40mph. I have done the following:

1. Flush/cleaned the radiator system and refilled with 50:50 water:AF. The system seemed fairly clean anyway.
2. Cleaned the outside of the radiator with a water blaster.
3. Checked the fans are both working - they are.
4. The A/C trips out at 3/4 on the temperature dial - I guess that's a self-protection mechanism.
5. The coolant level is stable - no leaks.

What else can I do? It's embarrassing chugging along on the Interstate in uphill sections doing 30-40mph, sweating with no A/C, to prevent a 'meltdown'? In idle, or stop/start traffic it works just fine. What can I do to improve the cooling capacity? Or is it just something to put up with, with the higher ambient temperatures of summer (90-100F)?

 

could be head gasket. bad thermostat. bad water pump. or clogged passages.

 

Check the lower hose to see if its getting hot. It should be hot to show that the thermostat is opening and allowing coolant to circulate. If not, it's the thermostat sticking closed. If stuck closed, then buy a Honda OEM thermostat from the dealer.

If not thermostat, then it could be your water pump gone out.

 

Thanks. Both hoses are hot. All signs seem to be pointing towards the (expensive to replace) water pump.

 

Is it the original radiator, radiator cap? It could be clogged. But again, if the water pump isnt pumping enough, that could be it also. When was the last time the timing belt/water pump was replaced?