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Cavalier's have a problem with running hot. I replaced the motor in this car due to some oil lube place EZ Lube messing up my computer. No, I can't prove it except when I brought it home, found wires disconnected. Assuming so as to buy their fuel cleaning and other recommended services. Another story.
In the previous motor I put in the lowest Tstat I could and it helped but the engine seemed to always run near the 3/4 side of the temp gage. This motor runs even hotter. I have gone thru making sure that the coolant lines are bleed out of air. The Water Pump seems ok. I'm going to go check the belt tension again tonight. I do notice that it does run warm even at freeway speeds. So I am thinking High temp Tstat? Or restriction somewhere. I'm going to drain the radiator and flush it. I am thinking to change the Tstat to one I know is lower because I did not change it from the motor I had shipped to me.  But outside of that, how can I get that fan relay to kick the electric fan on sooner? Same thing in other motor with fan turning on rather late in my opinion. I put in a manual switch and was happy except when I left it on for a dead battery. May put it back in and wire it on all the time but I'd like to leave it to turn on when needed. Also, this motor just seems to run warm all the time, even in cold of night. Other than that, it runs great.  

first...
Available engines engine for your 1999 Chevrolet Cavalier:
4 Cylinders 4 2.2L SFI OHV
Application: OE recommended temperature 180 degrees
Thermostat Opening Temperature Rating (°F): 180

radiator fan without AC



~~~~~~~~~~~~~~~~~~~~~~~~
with AC


radiator fan relay... ECM/PCM controlled..



or do you have the  4 Cylinders T 2.4L  motor.. i cannot keep track...  

the 98 sunfire models had problems with the radiator cooling fan relay socket terminals NOT gripping the pins on the bottom of the thermostat tight enough to send enough current to the radiator fan to properly cool the motor..

probing with a sharp fine tip tool can sometimes tighten the grip..


its a 99... OBD2.. plug in your scan tool.. check the engine coolant temp with the scan tool...  see if it matches the coolant temp with a hand held infrared temp gun..

you should be able in the live data mode to see the radiator cooling fan request...

with a 192F thermostat.. i usually see the radiator cooling fan turn on at 215 on normal GM cars.. and 228F on some corvettes..

the normal operation is for the coolant to circulate inside the block and head picking up heat.. until the circulating coolant reaches the opening temp of the thermostat.. at that point .. it exchanges with the cooler coolant in the radiator.. that influx of cooler coolant closes the thermostat.. at this point the radiator fan is commanded on my the ECM.. for a specific length of time.. sometimes by temp ...

this closing of the thermostat will allow the coolant in the radiator to stop so the airflow can remove some of the heat..

with a lower temp thermotstat.. you have several problems..    the internal engine circulation heats up and opens the thermotat..  exchanges coolant with the radiator.. but because this is happening much cooler that the design temp. the radiator fan does not come on. so its still hot when the stat opens again..   after 2 or 3 cycles.. there is no cooler coolant to close the thermostat..  so it opens farther and farther.. allowing faster and faster through the radiator..  the heat builds..  this is a cooling system runaway..   with the thermostat open wide.. even the ram air at speed is not enough to cool it..

i have another question.. is that car a ducted radiator car.. where the radiator gets it's ram air through a duct.. not directly through the grill..    or if with a grill.. are the flaps that keep the ram air through the grill from flowing out and around instead of through the radiator.????  if its a bottom breather like third generation firebirds and transams .. if the air dam under the core support is damaged.. it will over heat at freeway speeds no matter how much power you apply to the radiator fans..  

It's a 2.2 with AC. And your post about the under grill ducting may have an issue. And using the scan tool and compare with infrared is a good idea. I will check it later. Also, had a fender bender weds where some car pushed me into the car in front on the freeway. The brakes in this car are great. Stop well and a short distance. But not designed for two car braking. That car took off. Luckily my front bumper dove under her car. Small dent in the hood and the front bumper all scratched up. And the rear bumper has some dings in it. Her car bumper was all scratched up. When I'm feeling better , I'll go over the car in detail related to ducting etc. . I was thinking I can make some sheet metal under car louvers to force more air. Have access to sheet metal equipment at work. But Wondering if more debris being forced up would be worse. When I am over this flu, I'll be working on it and my jeep. And of course in this mix of repairs is the house. What is left is the drywall patching in the house due to a busted pipe.
Happy Thanksgiving.  

take a look at the bottom of the image.. item 41..
how is part #40 and 44 also..???






037 22581511 MOUNT. Radiator
MOUNT,RAD LWR. Required: 02For: J (1995-2005) (1995 - 1999). $6.32

040 22597499 SEAL. Radiator Support Mounting
SEAL,RAD AIR LWR(**VPI 1-877-846-8243). Required: 01For: J A/C MAN CONT(C60) (1995-1999) (1995 - 1999). $14.96

041 22699077 DEFLECTOR. Radiator Air
DEFLECTOR,RAD AIR LWR. Required: 01
DEFLECTOR,RAD AIR LWR(AT LWR RAD SUPT). Required: 01
For: JC (1995-1999) (1995 - 1999).
For: JF37 (1995-1999) (1995 - 1999).
For: JF69 (1995-1999) (1995 - 1999).
$62.96

042 22651589 BAR. Radiator and Front End Tie
BAR,F/END LWR TIE. Required: 01For: J (1995-2005) (1995 - 1999). $54.51

044 22597499 SEAL. Radiator Support Mounting
SEAL,RAD AIR UPR(**VPI 1-877-846-8243). Required: 01For: J A/C MAN CONT(C60) (1995-1999) (1995 - 1999). $14.96