Thermostat on a California '99 z28

**Gblo6689** · 03-24-2010, 11:21 AM

The Camaro I just bought was originally bought in California, from the business card in the original owner's manual. It is currently in Florida, where we have no emissions tests.
I started having some concerns when the car was running at 210 going down the road on a cool day. I pulled the coolant level stick and it is a little cruddy so I'm having that flushed regardless. The thing that confuses me is that if it was over heating It would move past the 210 mark, however the needle stays steady.
This has lead me to confer that the thermostat that is in it is a higher temp than the 195 stock. Could this be due to California emissions or just because someone replaced it and didn't put the correct one back in.
Also I was looking a getting a 160 to replace it. Can anyone recommend that temp or another?

**bamaz28** · 03-24-2010, 11:30 AM

mine ran about 208 in the summer here in bama, replace the sensor also for good measure if your concerned its cheap.

**Conflict** · 03-24-2010, 11:34 AM

that's not the actual temperature, In 99-02 they put the cold-Normal operating temp-explode coolant gauge in because people would freak out if the coolant cycle started.

**00z28bubba** · 03-24-2010, 11:57 AM

Originally Posted by Gblo6689

The Camaro I just bought was originally bought in California, from the business card in the original owner's manual. It is currently in Florida, where we have no emissions tests.
I started having some concerns when the car was running at 210 going down the road on a cool day. I pulled the coolant level stick and it is a little cruddy so I'm having that flushed regardless. The thing that confuses me is that if it was over heating It would move past the 210 mark, however the needle stays steady.
This has lead me to confer that the thermostat that is in it is a higher temp than the 195 stock. Could this be due to California emissions or just because someone replaced it and didn't put the correct one back in.
Also I was looking a getting a 160 to replace it. Can anyone recommend that temp or another?

180 will be fine for replacement. 160 you will need to change the fans settings to come on at much lower temps. the 160 will just stay open and just will be constantly recirculating the hot coolant as opposed to a lower temp coolant that was cooled by the fans. but the 180 will keep it around 200. if you have a tuner or access to tuning equipment go the 160 route and make one fan come on at 170 and both at 190. it should never go beyond 200 unless something is fudged.

**Cutlass** · 03-24-2010, 05:46 PM

The gauge isn't accurate on these because these cars run warm and that freaks people out. So GM just made them so they just sit there around 205 to 210 when the engine is up to operating temp which is anywhere from 190 to 225ish. It nothing to worry about.

**c5z28** · 03-24-2010, 05:50 PM

nothing to worry about about I have a 160 thermostat and it still reads at 209ish(dummy gauge)

**pajeff02** · 03-24-2010, 06:09 PM

Same. After installing a 180 degree thermostat the factory temp gauge still reads 205 all the time. On a scanner, the engine runs anywhere from 183 to 195 depending upon speed and load.

If you flush the cooling system -- which is strongly recommended -- be sure to drop the block drains as part of the process as quite a bit of fluid remains in the engine after draining the radiator and even pulling the thermostat.

**2000dreambird** · 03-25-2010, 04:38 AM

Originally Posted by pajeff02

Same. After installing a 180 degree thermostat the factory temp gauge still reads 205 all the time. On a scanner, the engine runs anywhere from 183 to 195 depending upon speed and load.

If you flush the cooling system -- which is strongly recommended -- be sure to drop the block drains as part of the process as quite a bit of fluid remains in the engine after draining the radiator and even pulling the thermostat.

Where are the block drains??

**2000dreambird** · 03-25-2010, 04:39 AM

Is there a way to tune the car so the gauge works right or would it be a senser swap

**pajeff02** · 03-25-2010, 04:54 AM

Originally Posted by 2000dreambird

Where are the block drains??

There are two. On the driver side there is a large brass plug above and behind the alternator. It takes a 17mm allen head socket to remove it (which you can get at any auto parts store). On the passenger side there is a smaller allen head plug above the starter that points straight down. It is metric, but I found that a 5/16" allen head had the tightest fit on our car to remove it. Upon re-installing the plugs, I utilized a thread sealant paste in lieu of teflon tape.

Originally Posted by 2000dreambird

Is there a way to tune the car so the gauge works right or would it be a senser swap

Nope. Some guys run aftermarket temp gauges on a pillar mount gauge pod. I have a Hypertech attached to my center console that monitors all sorts of things, including engine temp.

**Gblo6689** · 03-25-2010, 07:07 AM

So much info, thanks guys.
I'm actually having a friend of mine do the flush, he works at Firestone and it will just be a ton easier. I'm sure he'll do the drain plugs too, I'll remind him though just in case.
Glad to know that it isn't actually running at 210... Would hate to warp the heads or anything. Definatly going to put a realy gauge in it then.
I'll also be going with a 180 thermo. Don't want to screw with fan wireing or tuneing.
Thanks again guys.