I have a 98 - two years ago my truck did the same thing. Dealer check revealed is was some type of vent breather that is located in the very rear, under the pickup bed. It has somethign to do with the fuel system vent. Had a real fight with them about whether this was covered by my 100k mile warranty and finally won. Jim Moore
Water in engine-head gasket most likely.
A bad thermostat can cause overheating in a Nissan Frontier when the air conditioning is turned on. A bad compressor can also cause this.
A Nissan Frontier may be overheating because the radiator is cracked. A thermostat failure can also cause it to overheat.
There are pages and pages of things that can cause a check engine light. You need to have it checked with a scantool. Then the code can be diagnosed and repaired.
I had the same thing happen , i just kept driving it and it cleared itself!
A bad transmission gear can cause your 1999 Nissan frontier to shift hard. Low transmission fluid can also cause the transmission to shift hard.
If it is not speced correct for it then, yes.
yes
yes
With a scan tool after repairing the cause of the fault code.With a scan tool after repairing the cause of the fault code.
If the system has a full charge then the thermister is most likely the cause for it not working.
several things 1. no radiator coolant 2. thermostat is bad 3. needs new water pump 4. make sure engine/radiator fan is running