1994 Honda Accord EX, 2.2L VTEC, 251K Mileage

Can't tell if it is normal or something is up with my car.

I live in SoCal, and today was a hot 100F day. I had the AC on full-blast and it was cooling at around 55-60F, so the AC is cooling okay - though not the best. I found myself in bumper-to-bumper traffic for a few minutes with the AC on, and I saw the temperature gauge go above from the normal (few ticks below the middle mark) to roughly 3/4 of the gauge near HOT.

Call me paranoid, but could it just be the hot day and my AC turning on full-blast that caused the temperature to go way above normal? I immediately turned off the AC and turned on the heater to max, and the car went back to normal... Cooling fans are turning on.

Perhaps I should be a little more cautious when using AC on a hot day and in bumper-to-bumper traffic.

 

These cars have a very robust cooling system. So overheating is likely an indication of a fault. Suggest replacing thermostat. A "lazy" thermostat may not open as temp increases to allow additional cooling flow. You compensated by reducing heat load.

FYI, we have very similar cars w/ very similar mileage. I have driven mine in Houston heat, bumper to bumper w/ temp gauge staying just below halfway.

good luck

 

Thanks for the reply, TexasHonda. Was your Accord running with the AC on? So you are saying that with the robust cooling system (given no problems), the car shouldn't overheat, even with the AC on.

Also, I've measured the AC temperature at idle, and it is noticeably lower than when car is up to speed. Mine is at 55-60 during idle. Goes down to 40-45 during cruising speeds. Typical with yours?

The thermostat was replaced roughly 25K miles ago - what's the interval for replacement on the thermostat?

 

Was AC on? In Houston, AC is used nearly year round.

Your AC temps are OK, but idle temp seems a bit high. I look for 30-40 degF cooldown from air temps on floorboard pax side (recirculate air intake) to center vent exit.

Thermostats are not maintenance items. I've had them last a very long time. If thermostat was not OEM Honda part, suggest you replace. OEM thermostats perform noticeably better than aftermarket in warmup time and steady correct temp.

Make sure both cooling fans are coming on at 195F (IR temp gauge on thermostat housing). A temperature delay in the thermoswitch A closling could cause overheating. I have noticed that fans rarely come on at speed, and only come on a slow speeds w/ high heat load; traffic, AC, etc.

Another possibility is blocked condensor preventing good AC performance and radiator performance. Inspect closely and clean as indicated.

 

Discovery today... I was looking around, and realized that there are two fans for the cooling system. I just thought there was only one - the condenser fan had always been working and I hear it. On my 4 cycl, the fan on the drivers side is the condenser fan with the metal housing; fan on passenger side is the radiator "cooling" fan. I noticed after 20 minutes of driving, some idling, and getting the engine up to temperature, the condenser fan would kick on.

The cooling fan, however, did NOT... I looked at fuse No. 21 (20AMP), and it was blown. I put a new one in, turned the engine on, and turned on the AC. Heard a (boom) sound - fuse to the cooling fan popped again. (Turning on the AC turns both fans on, correct?). What is this madness?? Well I tried to hand-spin the radiator fan, and it was noticeably harder to spin than the condenser fan. This leads me to believe that the fan has a short and keeps blowing the fuse.

Well I think I found the root cause of my problem, only having one fan working. I am surprised that I just found this out... Here in SoCal, we are experiencing abnormally high temperatures, and I guess having only one fan didn't cut it. I don't usually turn on the AC and drive in traffic with the AC on.

I just ordered a replacement on Amazon as well as some more fuses. Hopefully this fixes the over-heating problem as well as my AC not working as well at idle.

 

It sounds like you have found the likely cause. Congrats!

 

Thank you TexasHonda for the feedback you've given. Happy to say that the cooling fan was indeed the culprit. I replaced it with a Dorman aftermarket one, and it works wonders. It is also quite loud...

AC also works well at idle, cooling right around 40F with ambient temps at 85F.