-Thermostat replaced 1yr ago..Bottom hose is warm
-Fan Switch works (on thermostat)
-Burp system (3 cycles)
-Overheats random and at Idle

Went for test drive with A/C off then let it idle waiting for fans to work they cycle twice and all while temp is normal and 15+ minutes pass and the fans havent turn on temp still normal then after its start creeping no fans and passed the 1/4 mark ...Turn it off let cool off turn on start to let it idle at 1/4 no problem no fan still...then creeps and TURNED on A/C for FANS... I noticed the fans turned on min.later then off with the A/C still on....it kept this cycle On/ Off min. burst with the A/C on..while starting to creep up in temp so I let cool and I burped the system for air then test drove around car runs normal

BTW While burping the system CEL - ECT sensor ( 2 wire Under Distbr.) HIGH AND LOW Circuit Input..

 

Check the resistance across the ECT, should be between 200-400 ohms when engine is heated up... and 1.5k-5k ohms when system is cool. then check voltage of the wire, should be 5v between the 2 wires, and should be 5v between the red/wht wire and body ground.

Check radiator make sure there's air moving though it and that the fins are straight and not stopped up with bugs or anything, and make sure there's good air flow coming from your fans and that they are pressed up against it enough where it's not just sucking all the air in the side of the fan body. Also may want to check the hoses and fittings to make sure nothing is stopped up in there or corroding closed like cholesterol does to our arteries.

 

when was the radiator last replaced? scaling is a major cause of overheating when everything appears to be working correctly

anymore i just replace radiators when cars are 10 years old. their ability to remove heat starts falling off and with the age even the newest integras are, if they are still on OE radiators they need to be changed out

 

You keep saying 1/4, proper operating temp. is at the 1/2 way mark, rad fan should turn on about the same time temp. gauge reads 1/2 way, [assuming ECT sending unit and gauge are good] when idling or in stop and go traffic, neither the rad fan or condensor fans need to be on when car is moving, [non stop and go], engine temp will stay at just under 200 degrees, and A/C head pressure will stay at around 150 or so PSI.

I will question the way the rad and condensor fans is working, on most Honda /Acura, if engine temp. reaches 200 degrees F. the rad fan will turn on, [pass. side fan] only, on USDM Integra if oil temp. sensor triggers the Rad Fan Control Unit, both the rad and condensor fans will turn on, it is the RFCU and oil temp. sensor that will also turn on the fans even ig ign. switch is of, [engine not running].

Depending on a number of things, once the engine temp. has reached that 200 degrees F., the rad fan will cycle on and off as needed, to keep engine temp. below 200 degrees.

When A/C is turned on, the rad and condensor fans should both be on as long as A/C clutch is engaged, [A/C turned on and compressor running]. 94

 

That's where it sits ..but creeps past to almost H when the fans dont turn on....(sometimes) fans they kick on while its already creeping toward 1/2 they bring it down but they turn off /on in short burst without bringing it down to pic above..(sometimes) its sits there like in the pic and both fans will come on and temp will stay the same...

Where is the RFCU ?
A/C on: both run...A/C off: (when kicked on)Both fans on. I haven't seen 1 fan on by itself.
Also its driving normal since the Burp..like I said its overheats random and only on Idle..

 

Sorry, not sure where the RFCM is, we do not have them on the CDM Integra.

It is beginning to sound like the ECT switch may be the problem, or possibly the rad fan relay, the rad fan is controlled "directly" by the ECT switch, if engine temp. is at 200 degrees or above the rad fan will turn on and stay on untill engine temp. drops below 200degrees.

If the rad fan is turning on and off with the temp. gauge showing more then 1/2 way, unplug the ECT switch and jump the connector, if rad fan runs continuously, replace the rad fan switch, if the rad fan is still turning on and off, jump or replace the rad fan relay, if there is still a problem check wiring to and from rad fan relay. 94