1992 accord, overheating

[j gresh]

Temp gauge reading high. no electric fan(s) operation while engine is running with ac off. both fans do come on when ac is on, but still the gauge reaches the red. No signs of leaks and the the coolant been change within a year. Engine does not make any noise. 40k on the vehicle. This is what i done and replace so far. Replace thermostat and gasket. With engine running temp gauge reading high. 1) jump temp sensor on top radiator hose outlet- no fan action. 2) jump temp sensor at lower radiator thermostat housing - both fans come on. 3) swap power window and electric fan relays - no fan action. With engine off and hot I jump the top radiator hose sensor - radiator fan on the pass side came on. when the engine is running and I urn on he heat the temp gauge drops down o normal. What else can I check. Is there any more relays, sensors or modules that can be tested? thanks for any help you guys can offer.

[accordztech]

is both hoses hot when it over heats, or one is cool? Check that.

Does the temp go down while driving?

[dj_ender]

Yeah I know, dumb question, but did you check and make sure the Thermo wasnt in backwards?

[j gresh]

Thanks for the response. No I did not check the radiator hoses. But when I replace the thermostat and bleed the system that hose was hot. I'm kinda sure the top radiator hose was hot. While driving at 65 mph the temp gauges reads 3/4, then goes to H while stuck in traffic. the only way I can get the temp down is by turn on the heat. It seems the car is using a little more gas than normal. The engine rpms are about 1500 when started in AM when the outside temp is about 75 degs.. Also the engine is starting buck and hesitate on acceleration after about 20 mins of driving. thanks for any clues to fix he problem.. last thing - the D display was flashing yesterday.

[99CcordMTF23]

The flashing D would be the transmission probably telling you that something is wrong with the engine. Did you replace the gauge sending unit? The tiny one?

[j gresh]

Funny. Honda does have 2 little alignment nipples on the gasket that slotted into the lower radiator hose housing. But when I started to replace the thermostat on the first go around. I remove the top radiator hose housing to replace the thermostat there it was missing - wrong location.. note: I just drove this car for about 30 mins and it did not overheat. what gives?? thanks for any help

[j gresh]

No. why do they have all these temp reading devices. Coolant temp switch A and B. coolant temp sensor, coolant temp gauge sender. Could it be the transmission fluid was getting real hot causing the the D to flash? autozone has the coolant temp sensor under the distributor for $18.00. honda dealer has no sensors for the car. Note: I just came back from a 30 min local trip and the car ran normal. huh

[accordztech]

Your honda dealer doesnt know shit.

Check the hoses when it overheats.

Flashing D light is something with the TCU. There is a FAQ on how to read that code, its fairly easy.

[I-Deal214]

I had this same exact issue the past week. First thing was to change the thermostat. That didnt work. then I noticed my fans wouldnt turn on when running hot only when AC was on. You might have to change the temp fan switch the one in front on the upper hose going to the head that did it for me. also check you r water coolant resevoir tank make sure theres not soot like substance if so flush your system and make sure you only use coolant and distilled water not faucet or hose or drinking water the more minerals the more heat it produces and boils distilled and radiator fluid doesnt boil.

[I-Deal214]

Oh and the flashing d is a trans code theres a thread on here that tells you what the codes mean check it the same as you would the check engine light with jumping the wire on the passenger side behind the plastic plate by the ecu. its on the thread also if you dont know were it is.
hope this helps.

[Noridetoolow]

Honda's are stupid easy when it comes to cooling....all the sensors aside, LOL. I could not quite follow all you did in your first post so Ill touch on some simple basics and questions...

1. Does the car run hot when the primary cooling fan is running? Fan on the battery side of the engine is the primary fan, the other is only for when the A\C is on (im pretty sure).....

YES running hot - means that your radiator is probably clogged, pull it and have it tested. If bad you can have it rerodded or simply replace it, they are like $60 on ebay shipped if I remember right.

NO not running hot - means your fan relay or some other trigger is failing. I believe this is what you are asking about anyway if I understand your post. A SIMPLE fix is to simply hardwire your fan to a source only powered when you turn on the car. This means the fan will run constantly when the car is running\ignition is on but this is OK and is DEF what you need to do until you figure out the issue. I had a DA Integra that had a fan issue, I hardwired it and left it that way forever....sometimes trying to figure out what is causing your fan to not work is just not worth the drama.

2. Running your heat is an old well known method to help cool an engine when its running hot, people have been doing this for years and years.

3. If your radiator is good, your fans are functioning properly and your thermostat is good, your probably looking at a faulty water pump though this is usually the last resort. If a Honda has a decent functioning cooling system, my experience has shown that its RARE to ever see the temp go over about 1/3 on the temp gauge, any time I noticed higher then that I found a problem. I must admit that this is one of the best cooling systems ive ever noticed in a car before. Just one of many things Honda did right.