I've change the:
thermostat
thermo fan switch
radiator cap

It's still running hot, around almost 7/8 to overheating. But it doesn't overheat.
There are 2 more sensors/switches below the distributor cap, should I change those as well? There is good flow of the coolant, so I don't suppose its the water pump.

Anyone?

Its a 99 Accord 4Cyl LX Manual 5 speed

 

Heres some information that may help you out:

There are 4 sensors that have to deal with the cooling system.

-The one 2-wire sensor located on the thermostat housing is a thermostatic switch that controls the cooling fans when the ignition is on; when the switch reaches approx. 195F the switch will close and both the "condenser" and "radiator" fans will turn on.
-The 2-wire sensor located below the distributor is the coolant temperature sensor for the engine computer. This is a variable resistance sensor, NOT a thermostatic switch.
-The single-wire sensor located below the distributor is the coolant temperature sender that sends the signal to your temperature gauge in your instrument cluster. Again, it is a variable resistance sensor. The sensor gets its ground-side through the cylinder head.
-The last sensor located on the coolant outlet housing (connects to your upper radiator hose) is a 2-wire temperature switch that controls the cooling fans when the ignition is OFF (This sensor is responsible for the fans continuing to run when the car is parked and off). This switch will activate if the coolant reaches around 225F, and will turn on only the "condenser" fan.

-By the way, although both cooling fans are technically just "radiator" fans, the terms caught on mainly from reference from older cars, that the "condenser" fan is the fan on the left, and the "radiator" fan is the one on the right (when viewed from the front of the car).

Heres an easy test to insure that your cooling fans, relays, fuses ect. are in working order:

Disconnect the connector on the 2-wire thermostatic switch located on the thermostat housing. Turn the ignition key to the on position. Use a small wire to jump the contacts on the connector. Both the condenser fan and the radiator fan should turn on. If not check fuses, relays, connectors, grounds etc. (this same test can be used to test the thermostatic switch located on the coolant housing near the front of the car, but jump the connector with the ignition key OFF and only the condensor fan should turn on).

Make sure your system is properly bled-out. With the engine cool, and turned off, loosen the bleeder screw located on the thermostat housing (12mm wrench). Add coolant through the radiator cap until a steady stream flows out of the bleeder scew, then re-tighten the screw.

I hope this all helps, try these tests and see what happens. Its also possible that the temperature sender for the instument cluster could be bad, or the new thermostat you bought could be faulty.

Also there is a ground connection that if not hooked up will cause your temperature gauge to read hot (even though the engine is NOT overheating). If you look at your battery on the negative side there will be 2 ground cables. The one longer/thicker cable attaches to the transmission/engine area near the front of the car. The second smaller cable is only about 6" long and attaches to the inner fender well. Make sure this cable is intact and clean. When I rebuilt my engine a few weeks ago, I forgot to re-attach this cable and the gauge read too hot (even though the actual engine temperature was fine). Once I re-connected and cleaned up that ground, the gauge read just fine.

-Good luck!

This information applies to the F22Ax and F22Bx engines as well, in the 90-97 accords.

 

when is the last time you FLUSHED and filled the coolant? might want to try that as it is cheap and easy.

 

Thank so much , the ground to the fender from the battery fixed my gauge ,and saved me from changing the pump 🙏