Hello, I am barrowing my step-father's Honda. I think it is an accord.

can you verify for me, what is this sensor?

Also, what size is the engine in liters? It has MANY problems. I am diagnosing them one by one. For starters, the headgasket is blown and leaking into cylinders 3&4 (far away from distributor). It only has 1 single radiator fan, and I saw pictures with 2. That's just for starts.

Is the sensor necessary? THe one I circled in broken off. I Know it is coolant, but, the car seems to run fine without it hooked up. I would like to diagnose the o2 sensor as well, anyone have the pinout for this engine?

 

ok I found two different pinouts. Is the car (94) obd2 or 1? I do not know where the ecu is, but I think it would be in a kick panel. SO I will go to the car now, and start taking apart kick panels to find the ECU. Then by the looks of the diagrams, the OBD1 has 2 rows... where the obd2 has 3 rows. That should tell me amirite?

 

Its obd1 and its a 2.2l engine. Not too sure what that sensor is.

 

I found the ecu! its under the carpet, haha. Yes I confirm, concur, OBD1 it has 2 rows not 3. Thank you for the post. Now, on to the diagnosis....

1. First, I used "copper head gasket sealer" to attempt a temporary head gasket fix. Last night I follow the procedure. Seems to be ok so far today I drove it about 10 miles and no issues yet.

2. I am going to discount to buy some new plugs, and get either a multi meter or a air/fuel gauge to test the closed loop operation. I want to see if the engine is using closed loop before I take any further steps regarding the tune/coolant sensors/map sensor/ etc... to verify the engine injection capability health.

 

Fan switch sensor. Cylinder 1 is the farthest away from the distributor.

 

96 Is when all cars were mandatory OBDII, it is OBD1 being a 94. That is the fan switch B which controls the cooling fans after the car is turned off.

Read this for all sorts of information on the cooling system.

https://honda-tech.com/forums/honda-accord-1990-2002-2/diy-c-cooling-system-2793650/

 

Thanks! So the leak is on cylinders 1&2 then. And I wont be needing that sensor, since the fan is hardwired on ignition already. *sigh


So I Went to the auto store and barrowed a multi meter (I AM OUT OF TOWN) And I could not get a reading from the white/red wire at the ECU for the o2 sensor. Either the o2 sensor is bad, or the wire is wrong, or the multi meter wasn't working for some reason, Or I had the wrong O2 sensor? Or maybe the car needs to be driving to be in closed loop?

Does anybody know if the ecu will use closed loop and flip the o2 sensor voltage while parked at idle? It normally goes 0v-1v back and forth but Ive never tried on a Honda before.