New Thermostat Replacement, Still Only Running At 180 Degrees. Why ?!

[Chaz9496]

I just got my thermostat replaced in my LS2. Before the replacement, I was getting a coolant temp of 171 to 180. Now after replacement, 180. The stat is a 198. Why only 180 ?! It's supposed to be at least 192 from what I've been reading. This was a $480 repair, and I wasn't confident this was the fix. I may be correct. I wasn't chancing doing this myself due to issues I read here tht could happen during dismantle. I'm not happy why it's not at 190+ like it should be. What should it be running at and what do I check for next ? This was on the shops snap-on scanner both before and after.

[Chaz9496]

Sorry, the above post wouldn't edit for some reason. OK, My last L200 heater got hot enough that you had to turn it to half it was so hot. This one doesn't get hot at all. I had a car in the past that everthing I did or replaced, nothing worked, it never got very hot. I hope this one isn't going to be another one. What do I look for now ?

[lrbraner]

Is there a chance the shop put in the wrong thermostat ?

[floridasl22002]

Did they burp the system after doing all the work to get air pockets out? Usually if the system has been emptied, refilled, etc, and the heater does not throw out hot air, then that's often a sign you have air in the system.

You can burp it yourself. Switch the heater to full heat, remove the coolant reservoir cap and let the engine run to get hot. Burps will show as bubbles in the tank. The coolant level may also rise and fall as air comes out. When the heater throws out hot air, you know that the system is burping itself free of air.

If that doesn't work, then there is something amiss and you need to take it back to the garage and get them to fix it. As has been mentioned before, it could be the Tstat was incorrectly fitted or possibly the wrong Tstat installed. Who knows? You might also have a coolant pipe that has collapsed internally and effectively flow. I have had that happen to me only once in a long time, but can happen.

[Rj 2000 LS2]

How are you measuring you're temperature?

What problem are you experiencing with the temp too low?

[Chaz9496]

Originally Posted by lrbraner

Is there a chance the shop put in the wrong thermostat ?

Nope, I got it from work at my cost. It's the only one we stock, 198 degree.

[Chaz9496]

Originally Posted by Rj 2000 LS2

How are you measuring you're temperature?

What problem are you experiencing with the temp too low?

Snap-On scanner. Service Soon light and warm heat. Possible open thermostat, rich code as well.

[Chaz9496]

I felt the kick panel and the core is getting hot, so I would assume something going on with the hvac box or clogged core fins. I have some work to do on it this weekend, so I'm going to pull the dash and check why the recirc door isn't working and check some things while it's accessible. Maybe I'll find something of inportance.

[02 LW300]

Is this an LS2 or a L200? LS2 is a v6 car and an L200 is a 4 banger. I have an Ls1 and an L200 both being 4 cylinder cars. If you remove the cabin air filter you should be able to see if the recirc door works.
Oe temp on the v6 is 198, Oe temp on the 4 cylinder is 180.

[Rj 2000 LS2]

Originally Posted by Chaz9496

Snap-On scanner. Service Soon light and warm heat. Possible open thermostat, rich code as well.

Are you certain they actually replaced the thermostat? If the same codes returned, they did something wrong.

Did you burp the system as described by others? If you have air trapped in the system, it could be causing your problems.

What type of coolant is in your system? Occasionally people mistakenly use the wrong type of coolant and if mixed, it will cause blockages. This could be your issue. I am just trying to brainstorm of possible issues.

Lastly, the rich code could be completely unrelated. Don't be fixated on ONE potential cause. Keep your mind open as you continue to diagnose the issue(s). Likewise, only work on one idea at a time. Some times garage gurus get lost because they did too much at one time and before you know it the forest and trees look the same.

What were the codes?

[pierrot]

Originally Posted by lrbraner

Is there a chance the shop put in the wrong thermostat ?

If one looks at RockAuto.com for a thermostat then there are three available as 192, 197, and 198 degree types. However, if one looks at Autozone and O'Reilly Auto Parts there are also 180 degree thermostats sold by both of them. These are wrong and should never even be offered for sale on GMs 3.0L V6 engine. While I cannot know what company was used to provide the replacement parts for the OP's mechanic to use, it's clear that they COULD have installed a thermostat which is below specifications for an LS2's cooling system. The mechanic must be asked about this possibility.

[lrbraner]

Originally Posted by Chaz9496

Nope, I got it from work at my cost. It's the only one we stock, 198 degree.

Possibly defective then.

[Chaz9496]

Originally Posted by 02 LW300

Is this an LS2 or a L200? LS2 is a v6 car and an L200 is a 4 banger. I have an Ls1 and an L200 both being 4 cylinder cars. If you remove the cabin air filter you should be able to see if the recirc door works.
Oe temp on the v6 is 198, Oe temp on the 4 cylinder is 180.

An LS2. I had an L200, I sold last year. Actually I got the recirc door to close. I pushed the button to on just to see if it would activate again. Come to find out, it did sitting at a McDon
ald's drive thru this week. I heard it close, when last weekend I tried to close it and it wouldn't. Most of the time it didn't work at all. I kept it closed to check the heater temp to see if it gets any hotter. So far, it hasn't been cold enough to really tell. Tomorrow morning "Fri" may be. We'll see.

[Chaz9496]

Originally Posted by pierrot

If one looks at RockAuto.com for a thermostat then there are three available as 192, 197, and 198 degree types. However, if one looks at Autozone and O'Reilly Auto Parts there are also 180 degree thermostats sold by both of them. These are wrong and should never even be offered for sale on GMs 3.0L V6 engine. While I cannot know what company was used to provide the replacement parts for the OP's mechanic to use, it's clear that they COULD have installed a thermostat which is below specifications for an LS2's cooling system. The mechanic must be asked about this possibility.

It really doesn't matter, because I bought the stat from work at O'Reilly's and it was the only one we had in stock, a Murray 198 degree as stated above and the shop's not going to change ir out for free, I wouldn't figure if they did everything correct. The stat would be my problem.

[pierrot]

Originally Posted by Chaz9496

It really doesn't matter, because I bought the stat from work at O'Reilly's and it was the only one we had in stock...... The stat would be my problem.

Ooo... that's kind o' painful to see. The cooling system is linked to the emission system and, as a result, the correct minimum temperature of the coolant mixture is required for the emission system to operate correctly. Since the thermostat now opens too soon - resulting in a lower operating temperature of the cooling system for an extended period of time - it could result in the unnecessary appearance of a DTC or two. (I'd be happy to be wrong about that!)

[Chaz9496]

Does anyone know a part number for the recirc door actuator ? I can't cross one at work or find one online. Rock Auto doesn't even list one, that I know of. Is there a chance it's the hvac button that controls it is not working ? It works intermittantly, but most of the time, it doesn't. I guess I can test the switch with a multimeter as well. Thanks for the great replies to help.

[pierrot]

Originally Posted by Chaz9496

Does anyone know a part number for the recirc door actuator ? I can't cross one at work or find one online. Rock Auto doesn't even list one, that I know of. Is there a chance it's the hvac button that controls it is not working ? It works intermittantly, but most of the time, it doesn't. I guess I can test the switch with a multimeter as well. Thanks for the great replies to help.

In the link below the item you're looking for is #4, air inlet actuator, p/n 22732652.

https://www.gmpartscenter.net/v-2000...ter-components

This part is NLA from GM. Look for it in wrecking yards as I have. I picked up my replacement and a spare from Pick Your Part wrecking yards. Otherwise, look up wrecking yards through www.car-part.com.

[Chaz9496]

Yep, that's the part I tried to cross at work last week that came up "No Rusults" trying to cross it. It's the same number I found as the recirc actuator. Anyway, I did take out the air cabin filter and with the recirc light on, the flaps were still open, but the switch was activating, then stopped again. It still wasn't opening and closing like it should. There is an L100 at the yard here that has the column gone, so if it takes removal of tbe dash to replace, which I imagine thats the simple way, It's a little more easier to remove, at least for the column part of it.

[pierrot]

Originally Posted by Chaz9496

...There is an L100 at the yard here that has the column gone, so if it takes removal of tbe dash to replace, which I imagine thats the simple way, It's a little more easier to remove, at least for the column part of it.

I presume that you're referring to the steering column. If so, that part has nothing to do with removing the air vent/recirculation actuator. That part is located very near the interior firewall on the passenger side and close to the farthest righthand side of the evaporator/heater core case. I had to remove the glove box (which includes its door and the BCM which sits atop the box [separate the BCM from the glove box]) and the passenger side lower vent plenum to have access to the actuator. When removing the actuator press it forward towards the firewall in order to separate it from the rod which is part of the vent door. I failed to do this and ended up breaking that rod , forcing me to pull a donor vent door assembly from another wrecking yard car so that my replacement circulation actuator could work again after installing it.

The rod and door are molded as one integral piece. Gluing that special plastic is an inadequate repair for the continued use of that part. I know from experience. So DON'T DO WHAT I DID! BE SMARTER THAN I WAS!!

[Rj 2000 LS2]

For sheets and giggles, I would change the temperature sensor and see what happens. Also, make certain there is no air trapped in the coolant system.