My 96 Honda Accord LX 4 Cyl Non-VTech is having another weird problem again, in fact it's three issues tied into the same problem with a minute of a coolant leak.

TO kick things off the car is over heating, first thing I noticed is that the fan didn't spin when it got hot {roughly 75% on the meter}. Now because my speedometer sensor needed to be replaced I had to take apart the thermostat housing and I figure while I'm at it replace the thermostat and the sensor to boot. So it can't be the thermostat or the thermostat sensor. In fact I've replaced ever sensor left/top left of the engine at this point.

I also observed when the car started to over heat that the Oil Light came on while it was in idle but disappeared when the car is in motion, later it would flash on and off. Prior to driving I was topped off on all fluids, my coolant, oil, transmission, everything was at optimal levels and the light was still going on.

With my last Oil Change I replaced the Oil Pressure sensor and I've even plugged in my OBD to check for any other trouble codes, besides the O2 sensor a new trouble code came up: p1491 Cnf Mod- Definition Not Found. But this only came up after I got done fixing my surging issue with my car. As for the tiny coolant leak once the cars been driven long enough a small drip-drop leak can be spotted far back behind the engine, I didn't see any leaks coming from the hose mainly because the hoses come up over the transmission into the thermostat housing.

If anyone has any ideals to solve this puzzle box please do assist.

 

Lets take this a little bit at a time........

You have a coolant leak, you need to fix that. Then be sure to properly bleed the air from the cooling system.

Next, pull the connector from the fan switch on the t-stat housing. Use a paper clip or something and jump/connect the wire side terminals. Turn the key to the on position (pos II) - BOTH fans should run, do they?

PS- I would also fix that exhaust leak you have at the exhaust manifold....might just solve your O2 code you are getting.

 

Also, if your oil pressure light is coming on(even after you replaced switch). Especially at low rpm's I would suspect true low oil pressure(