Hi, my 1997 Accord Dx 2.2L 4 cyl. 5 spd. m.t. 104000 miles. When driving on the highway the temp gauge rises to about 3/4 when using the AC. When I turn off the AC it goes down some, but when I turn on the heat full blast it returns to normal. This only happen when driving at highway speeds in warm weather. I noticed that around 30%+ of the radiator "fins" are missing. I had the coolant flushed last year but that did not resolve anything. I can hear the fans running when I turn off the car. My guess is the radiator needs to be replaced along with the thermostat. The coolant level is fine. Any help would be appreciated.

 

I tend to agree w/ your diagnosis of damaged radiator needs replacement. I've found that cooling is adequate w/o any fans as long as car is moving at 20+ mph. AC will even work at decent speeds w/o fans. So overheating at speed is likely an indicator of damaged radiator.

To be sure I would first replace thermstat w/ OEM Honda thermostat. They are worth the extra bucks. If same performance, then a new radiator. I've found the inexpensive ebay radiators work fine. They were Chinese manufactured, but don't remember brand.

A used radiator may be an option also. Check car-part.com for a unit near your zip, plenty available for around $50.

good luck

 

If 30% of the radiator fins are missing, I bet another 30% or 60% are corroded to the point that they'll come off if you sneeze nearby. That right there sounds like a good reason to get a new radiator.

 

I bought a new rad from Autozone for my 97
It was not expensive.