My 96 LE Camry, 4 cylinder started to over heat in Dec. Here is what I have done and what I still see as an issue. Any input would be helpful..Thanks

Dec:
replaced the thermostat. Car continued to run hot.
Jan:
replaced water pump, thermostat sensor at the thermostat housing, number one fan relay. Continued to run hot
Jan:
Went to radiator shop, determined thermostat was not working, replaced aftermarket with OEM and replaced heat sensor at the bottom of the radiator.

Side note is the radiator is less than two years old and an OEM part

The car runs normal while on the road with no issues. Until I come to a stop and then the gauge that is running just shy of half, which is where it has always run. Will creep up to 3/4 and stay there. I've watched to see if the number one fan comes on and it will for a few seconds then kick off. Once I start to drive the gauge will return to normal. If I turn on the AC it will run normal no matter what. That's because both fans are running

I'm really at a lose as to what it could be now. I had a local radiator shop check the temp at all ranges and its running in operating temps

Something is not telling the number one fan to kick on earlier.

Ideas???? Again thanks

 

As the engine is only overheating when the car is not moving the issue could be one or more fans.

Make sure both fans work when the AC system is on.

The test of the fan system is to unplug the electrical connection at the temp switch on the bottom of the radiator. When this switch is unplugged both fans should turn on (ign switch is on). The system is designed that when this temp switch opens (not closes) the fans turn on. If the plug is removed and the don't operate there is a problem with the wiring or a relay.

You can simulate the cooling system action by removing the radiator cap and installing a thermometer such as cooking into the coolant. Let engine warm up. Both fans should turn on when the coolant temp reaches around 199F. If not and now the temp gauge is climbing something is wrong in the wiring, one of the relays controlling the fans, etc.

 

Both fans work when the AC is on, I did unplug the temp switch at the bottom of the radiator and the fans both run all the time. I keep thinking its in the number one fan relay for some reason. I did replace that with a Bosch part, but wonder if that's what causing the fan not to kick on sooner.

I did have the radiator shop that installed the new T-stat run a test and even when the temp gauge reads 3/4 mark its running with in right temp range.

This really boils down to the gauge moving up once the motor is hot without the AC on. The number one fan will kick on when the temp gauge hits the 3/4 mark, comes back to just about half and then will go back up and repeat itself.

 

Given the shop tested the coolant temps are you sure the coolant was actually too hot?

The needle on the temp gauge should stay put even with engine idling and A/C off. The fan(s) will cycle but the needle stays put.

If coolant temps are OK might be the sender for the temp gauge is bad.

 

Where is the "sender" for the temp gauge?

 

Should on the manifold where the coolant exits the cylinder head. Has a one wire electrical plug. Wire might be yellow/green in color.

 

Thanks I'll have a look at that.

 

I wanted to followup with you in the solution. I changed the temp sender with an OEM part and that was the issue. I drove the car all weekend and the gauge did not move once! Even in the hot weather we had.

Thanks for the help, I learned thought all of this that OEM parts are the way to go on abuot any fix.