blkmonday

i have a 99 cavalier with a 2.2..its overheating. at what temp should my fan be turning on? it turns on at 195..im wandering if the fan temp sending unit is ok? i changed the relay, but that didnt make a difference. the radiator is boiling over and im losing anti-freeze through the overflow spout. otherwise i dont see a leak and i dont see white smoke in the exhaust. the fan is working at 195...just not sure if thats too hot. i hope its not a head gasket i only have 60k.....maybe the water pump?

hotrod_chevyz

get a 160 thermostat.

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blkmonday

update...this morning i decided after reading a bunch of posts to purge the air out of the cooling system. there was definately some air in there. i also changed the cap. drove it around for awhile today (although it was a little chilly out and i didnt sit in any traffic) seemed to be better. it seems like the fan is kicking on at around 210 or 200...that still seems a little hot to me. im going to continue monitoring it and i guess we will see what happens. the 160 thermostat seems like the next step that and maybe a new fan switch with a lower setting...i hear there are adjustable ones out there that can be ordered through autozone. we will see

muff34

thermo stat opening spec for 2.2 is 195 degrees. fan is likely 200 -205 seeing as how boiling temp for water is around 212 degrees F. how old is the coolant ? if it is original change it, it is likely weak. Would not hurt to get a pressure test done on cooling system. just my two cents

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exalteduser

if you are boiling at 195 then you have a problem since plain water boils at 212, the correct coolant mixture should have a much higher boiling point

Jmrec100

I put in a manual switch that I can manually turn on the fan when sitting in traffic. The temp gauge goes 3/4 and more before the fan kicks in. So I manually turn it on. I have to put in a timer though because sometimes I forget to turn it off.
Id like to hear more about the adjust fan switch? I thought it was controlled by the computer?

jakegday

it doesnt matter what temperature thermostat you put in, that thermostat isnt gonna magically communicate with the computer and tell it to turn the fan on sooner, if your fan is set to turn on at 195, and you have a 160 degree thermostat in there, the fan will never turn on, cuz it will never get that hot,

and putting in a "manual override" cuz your guage goes up to 3/4 is just retarded, its supposed to go that high, thats perfectly normal, if it wasnt supposed to go that high then GM would have have put that red line on the 3/4 mark, if its below red, or the H, its perfectly fine


also blkmonday, you have a 99 2.2, these engines have a habit of head gaskets going out, no matter how many miles, just to let ya know....

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2001 Grand Prix GT: cat/u-bend/resonator delete, zzp PLOG, Custom Intake, DHP PCM,
1981 Fairmont 6cyl 3 speed

blkmonday

yea i have heard these head gaskets are garbage. so far changing the anti-freeze and bleeding out the air in the system has worked....the car really hasnt been driven much since i did the work and its been cold here in ct up untill this weekend so we will see for sure if that worked this week. now im getting a nasty grinding sound coming from the front of the engine, sounds like a bad pulley tensioner or maybe a bad ac clutch bearing. it quiets when the ac is turned on. ill have to investigate further. for a car with such low miles im pretty disapointed.

hotrod_chevyz

They have a habit of blowing head gaskets because people think 3/4 on the gauge is okay. A 160 thermostat will cure the problems, it will never run hot again. In fact you would have to put a piece of cardboard in front of the radiator just to get the heater to work during the winter, just like my dad has to on both of his cavs..wich BTW are both bored out and machined for a few extra ponies.

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z24forlife

Hello the grinding sound could also be your water pump..going

Id like to know what proceedures to take to flush my anti-freeze for fresh ant-freeze... it looks like its going on the brown side... so changing it would be a good idea..

any help or advice..
ciao

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z24forlife