Recent Topics
Chevy Commercial Parody
by 02SE. 12/17/18 02:37 AM
Fluctuating Tachometer Fixed!
by jerseyguy123. 12/17/18 02:10 AM
2015 MB GLA250: OEM oil vs Mobil1 Formula M
by SlavaB. 12/17/18 12:39 AM
Shotgun Ammo
by user52165. 12/16/18 10:24 PM
Bought a Model 3 for wifey
by JeffKeryk. 12/16/18 09:01 PM
Maybe I'm crazy.
by TRDPRO85. 12/16/18 07:50 PM
Pacer EON E-11 Synthetic Motor Fluid
by Brandon9797. 12/16/18 07:46 PM
Reuse transmission fluid??
by FFeng7. 12/16/18 07:35 PM
Amsoil SS color change
by BigShug681. 12/16/18 07:21 PM
Why don't owner's manuals specify the oil type
by OilUzer. 12/16/18 07:13 PM
belt tensioner problems
by mobilaltima. 12/16/18 06:57 PM
How bout them Patriots
by 53' Stude. 12/16/18 06:36 PM
Hand held Ham radio suggestions
by littleant. 12/16/18 05:20 PM
Ford 2.3 EB's using 87 vs 91/93 octane
by Whimsey. 12/16/18 04:48 PM
Oil analysis pump tube?
by maximum6. 12/16/18 03:56 PM
Mahle charcoal lined filter..the best!
by TiGeo. 12/16/18 03:45 PM
Newest Members
stantaur, Brandon9797, Landngroove, DanielH, Cpcz9382
66700 Registered Users
Who's Online Now
27 registered members (53' Stude, ctechbob, bbhero, ChristianReske, 1345, Bama, 3 invisible), 854 guests, and 44 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics295,172
Posts4,929,126
Members66,700
Most Online2,553
Oct 27th, 2018
Donate to BITOG
Previous Thread
Next Thread
Print Thread
Hop To
Page 1 of 2 1 2
Failing Thermostat? #4582713
11/23/17 09:08 AM
11/23/17 09:08 AM
Joined: Apr 2014
Posts: 1,343
South Central PA
Delta Offline OP
Delta  Offline OP
Joined: Apr 2014
Posts: 1,343
South Central PA
So recently with it getting cooler the truck is not warming up like it should or staying where it used to. This is about a 20 minute ride around town:



Normally it would be at the notch right before 210. Was that way last winter. The odd thing is I do have heat, although I don't think it is as warm as it once was. Upper radiator hose is warm, but not hot. Lower is barely warm enough to tell. Clutch fan seems to operate as normal. Could this be a sign the thermostat is going out, or something else?


'17 VW GTI 2.0T - 6MT - 11K - Edge 0w40
'15 Camry SE - 2.5 - 22K - PP 0w20
'99 S10 - 2.2 5MT - 157K - PP 10w30
Re: Failing Thermostat? [Re: Delta] #4582716
11/23/17 09:11 AM
11/23/17 09:11 AM
Joined: Feb 2013
Posts: 11,100
Phoenix, AZ
Nick1994 Offline
Nick1994  Offline
Joined: Feb 2013
Posts: 11,100
Phoenix, AZ
Probably a bad thermostat. My grandparent's Trailblazer did the same thing.

Do you have a code reader? Or know someone with one?

If so, plug it in and see what the computer says the temperature is, sometimes those gauges aren't that accurate.

Also, OEM thermostat or nothing. We had a Stant put into their Trailblazer and it started running hot, Stant replaced with another Stant still running hot. Then got an OEM and it was a lot better. Turned out the Stant had a smaller opening that the OEM, we used a micrometer and it was somewhere around a 10-12% smaller opening.


2015 Hyundai Sonata 2.4L 89k Motorcraft Synthetic Blend 5w30 & OEM
2000 Toyota Camry 2.2L 231k Valvoline 5w30 & Fram Ultra
1996 Jeep Cherokee 4.0L 147k Mobil 1 HM 10w40 & Fram Ultra
Re: Failing Thermostat? [Re: Delta] #4582760
11/23/17 09:58 AM
11/23/17 09:58 AM
Joined: Sep 2014
Posts: 1,491
Toronto Canada
WobblyElvis Offline
WobblyElvis  Offline
Joined: Sep 2014
Posts: 1,491
Toronto Canada
Most likely the thermostat. As Nick said I would consider an OEM unit. The quality of the aftermarket parts has taken a nose dive.

Re: Failing Thermostat? [Re: Delta] #4582802
11/23/17 10:49 AM
11/23/17 10:49 AM
Joined: Aug 2008
Posts: 21,314
ON, Canada eh?
StevieC Offline
StevieC  Offline
Joined: Aug 2008
Posts: 21,314
ON, Canada eh?
Thermostat. Surprised the ECU hasn't set a code for the engine not reaching operating temperature.


'18 Dodge Grand Caravan GT - AMSOIL SS 5w20
'06 Santa Fe - 535,000km AMSOIL SS 0w30 / ATF
Re: Failing Thermostat? [Re: Delta] #4582826
11/23/17 11:06 AM
11/23/17 11:06 AM
Joined: Oct 2008
Posts: 967
Iowa
Nyquist Offline
Nyquist  Offline
Joined: Oct 2008
Posts: 967
Iowa
Originally Posted By: Delta
So recently with it getting cooler the truck is not warming up like it should or staying where it used to. This is about a 20 minute ride around town:


Normally it would be at the notch right before 210. Was that way last winter. The odd thing is I do have heat, although I don't think it is as warm as it once was. Upper radiator hose is warm, but not hot. Lower is barely warm enough to tell. Clutch fan seems to operate as normal. Could this be a sign the thermostat is going out, or something else?


As others have said, the thermostat is probably partially stuck open. I had this on our Cobalt, and the symptoms were similar. It would only allow the engine to reach a temperature of 168F on the open road. I would swap it out before it does move again and gets stuck in a completely closed position and will not open which would cause over-heating.

As for the CEL, it will only illuminate that if the PCM cannot reach a closed loop condition. For some engines, that is as low or lower than 120F.

Last edited by Nyquist; 11/23/17 11:07 AM.

2015 Chevy Traverse 3.6L (LLT) Mobil 1 5w30 w/ Fram Ultra
2017 Chevy Cruze Hatchback 1.4L (LE2) Mobil 1 5w30 w/ Wix
Re: Failing Thermostat? [Re: Delta] #4582883
11/23/17 12:02 PM
11/23/17 12:02 PM
Joined: Mar 2004
Posts: 1,492
Flaherty, KY
92saturnsl2 Offline
92saturnsl2  Offline
Joined: Mar 2004
Posts: 1,492
Flaherty, KY
Most modern GM vehicles will set a P0128 if the coolant temp is low, or not reaching operating temp fast enough. I believe the trigger is around 160-170F, and x number of minutes to reach it. I can easily set the code by installing a 160*F thermostat, whereas a 180F won't set it.

You should plug in a scanner and see what the actual coolant temp is. Torque app and cellphone/bluetooth adapter is an easy method. Many GM vehicles have a separate coolant temperature sensor for the gauge and ECU. If you replace the thermostat and that doesn't change the temperature reported, I would look at the coolant temperature sensor. They are cheap and usually easy to replace.


1985 F-250HD 7.5L 4x4 135k- Castrol GTX 15w-40 HDEO
04 Odyssey EX 184k PUP 0w-40
96 Maxima GLE 254k QS Defy 5w-30
07 Chrysler Pacifica Limited 4.0L 134k Chevron Supreme 5w-20
Re: Failing Thermostat? [Re: Delta] #4582939
11/23/17 01:09 PM
11/23/17 01:09 PM
Joined: Apr 2014
Posts: 1,343
South Central PA
Delta Offline OP
Delta  Offline OP
Joined: Apr 2014
Posts: 1,343
South Central PA
Thanks for the replies. I've had a sneaking suspicion the engine isn't getting warm enough, you'll notice the oil pressure sits higher than it used to. I'll get the parts tomorrow. Probably will get new hoses while the coolant is drained. If it isn't the issue it's preventative maintenance anyways.


'17 VW GTI 2.0T - 6MT - 11K - Edge 0w40
'15 Camry SE - 2.5 - 22K - PP 0w20
'99 S10 - 2.2 5MT - 157K - PP 10w30
Re: Failing Thermostat? [Re: Delta] #4583037
11/23/17 03:47 PM
11/23/17 03:47 PM
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
Garak Offline
Garak  Offline
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
I would change it out. From the vintage of your truck, it looks like you're fortunate enough to have a GM of the vintage where the temperature gauges were actually very useful at discerning stuff like this.

On second thought, that truck is a ticking time bomb with that thermostat. Bring it up here, I'll take the risk and take it off your hands. wink


Plain, simple Garak.

2008 Infiniti G37 - Shell ROTELLA T6 Multi-Vehicle 5w-30, NAPA Gold 7356
1984 F-150 4.9L - Quaker State GB 10w-30, Wix 51515
Re: Failing Thermostat? [Re: Garak] #4583043
11/23/17 03:57 PM
11/23/17 03:57 PM
Joined: Apr 2014
Posts: 1,343
South Central PA
Delta Offline OP
Delta  Offline OP
Joined: Apr 2014
Posts: 1,343
South Central PA
Originally Posted By: Garak
On second thought, that truck is a ticking time bomb with that thermostat. Bring it up here, I'll take the risk and take it off your hands. wink


Anything's possible for the right price wink

A 2wd 4 cylinder S10 would not do very well in Canadian winters, lol.


'17 VW GTI 2.0T - 6MT - 11K - Edge 0w40
'15 Camry SE - 2.5 - 22K - PP 0w20
'99 S10 - 2.2 5MT - 157K - PP 10w30
Re: Failing Thermostat? [Re: Delta] #4583059
11/23/17 04:23 PM
11/23/17 04:23 PM
Joined: Jul 2017
Posts: 376
PR CA, USA
2strokeNorthstar Offline
2strokeNorthstar  Offline
Joined: Jul 2017
Posts: 376
PR CA, USA
I wonder if those temp gauges work on Chevys. Most cars since the 80s-90s just show 1/2 way from about 170-220. They don't mean much.

Re: Failing Thermostat? [Re: Delta] #4583076
11/23/17 04:48 PM
11/23/17 04:48 PM
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
Garak Offline
Garak  Offline
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
Originally Posted By: Delta
A 2wd 4 cylinder S10 would not do very well in Canadian winters, lol.

You'd be surprised. I throw my tractor wheel weights in the back of the F-150, and it's fine with two wheel drive. wink Some years ago, a buddy and I were going up a snow covered hill, with remarkably the same tires, two wheel drive, he had a GM and I had my Ford. He couldn't understand how I got up so easily when he was struggling with it. Over 300 lb of weight over the rear axle helped, I guess.


Plain, simple Garak.

2008 Infiniti G37 - Shell ROTELLA T6 Multi-Vehicle 5w-30, NAPA Gold 7356
1984 F-150 4.9L - Quaker State GB 10w-30, Wix 51515
Re: Failing Thermostat? [Re: 2strokeNorthstar] #4583077
11/23/17 04:49 PM
11/23/17 04:49 PM
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
Garak Offline
Garak  Offline
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
On the GMs I had experience with, they worked until around this generation of truck, at least. You could actually see when the thermostat cycled or the electric fan kicked in while sitting and idling.


Plain, simple Garak.

2008 Infiniti G37 - Shell ROTELLA T6 Multi-Vehicle 5w-30, NAPA Gold 7356
1984 F-150 4.9L - Quaker State GB 10w-30, Wix 51515
Re: Failing Thermostat? [Re: Garak] #4583095
11/23/17 05:12 PM
11/23/17 05:12 PM
Joined: Apr 2014
Posts: 1,343
South Central PA
Delta Offline OP
Delta  Offline OP
Joined: Apr 2014
Posts: 1,343
South Central PA
Originally Posted By: Garak
On the GMs I had experience with, they worked until around this generation of truck, at least. You could actually see when the thermostat cycled or the electric fan kicked in while sitting and idling.


Yup, especially the voltage one. During high electrical loads it will move around a bit. The temp gauge will normally move to the 210 range going up the mountain at high RPM's. Have to keep the revs up or you're in for a bad time laugh


'17 VW GTI 2.0T - 6MT - 11K - Edge 0w40
'15 Camry SE - 2.5 - 22K - PP 0w20
'99 S10 - 2.2 5MT - 157K - PP 10w30
Re: Failing Thermostat? [Re: Delta] #4583243
11/23/17 09:07 PM
11/23/17 09:07 PM
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
Garak Offline
Garak  Offline
Joined: Dec 2009
Posts: 26,258
Regina, Saskatchewan, Canada
You could see all kinds of nifty things when the cabs first got electric fans. wink


Plain, simple Garak.

2008 Infiniti G37 - Shell ROTELLA T6 Multi-Vehicle 5w-30, NAPA Gold 7356
1984 F-150 4.9L - Quaker State GB 10w-30, Wix 51515
Re: Failing Thermostat? [Re: Delta] #4583715
11/24/17 01:58 PM
11/24/17 01:58 PM
Joined: Apr 2014
Posts: 1,343
South Central PA
Delta Offline OP
Delta  Offline OP
Joined: Apr 2014
Posts: 1,343
South Central PA
Update:



Assuming the typical Chevy position (joking, been a good little truck!). Replaced the thermostat and hoses a couple hours ago. Did not change the temperature gauge reading, but I did notice the hoses were original (dated September 1998 shocked ) and the heat was noticeably warmer afterwards. Went and replaced the coolant temp sensor as well. It probably needed a coolant refresh anyways so it was all needed in hindsight. Don't know if its ever had a coolant change, but it drained fairly clean with only staining on the housing.

Here's a temp reading from the heat, seems nice and toasty now.



'17 VW GTI 2.0T - 6MT - 11K - Edge 0w40
'15 Camry SE - 2.5 - 22K - PP 0w20
'99 S10 - 2.2 5MT - 157K - PP 10w30
Page 1 of 2 1 2

BOB IS THE OIL GUY® Powered by UBB.threads™