I'm sorry there are probably many threads on this subject already, but I am fairly new at this so please bear with me. My problem is I have a 97 maxima that has had a new radiator, new water pump, and two new thermostats put on in the last week. Car has 230,00 miles on it. As long as you don't drive far and keep the speed about 40 miles an hour you are ok for a little while, but will eventually start overheating. The fans run and when it gets really hot you can turn the heater wide open and the heat hand will come back down to the normal range. I have burped the air out of the car until it has literally puked. Car has been to dealership and they tried to fix and didn't know what else to do. They did a compression check on it and they said it was not showing a cracked head. Besides getting hot the car runs and drives like a dream even with all the mileage. I am at my wits end on what else to do to this car. Any help would be appreciated.

 

Did you make sure, you took both block off caps off the radiator before installing the hoses. Ive seen then happen on several occassions.. Feel both hoses while the car is running are they both hot ? or at least with in 10 degreese of each other. Verify with scan tool if possible that car is actually overheating and not just a faulty guage.

 

cats clogged causing overheat?

 

Clogged cats would show as a loss of power when the engine is warm.

Is the cat actually boiling over or is the gauge only showing a hot condition?
As mentioned, verify that the engine is really running hot and it's not just a sensor issue.

 

Check your fans. They might be intermittently shutting off and you might not be noticing it. The next time the temperature starts to climb, pull over and pop the hood and make sure both fans are spinning.

 

^^^i would check the fans too, my car over heats because i only have one fan hooked up on running. also maybe checking the radiator cap as well, may not be keeping the pressure it needs to hold

 

i know this sounds stupid but did yo check to make sure you have a 50 /50 mix of radiator fluid.Many times you forget the little things.

 

Thats true this can be causing excessive boiling and putting air into the system. My guess is that there is still air trapped in there and the coolant isn't getting around properly, try doing another complete drain and fill.

 

Was the car overheating before you had all the work done? If it wasn't, I would look at the thermostat. There have been many problems with non-Nissan thermostats or it was installed backwards. But it sounds more like a thermostat that isn't opening all the way.. Backwards installation ususlly overheats pretty quick.