Tach and shift light wrong with new thermostat?
Thread Starter
Safety Car
Joined: Nov 2005
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From: Huntsville Alabama
Tach and shift light wrong with new thermostat?
Did a cam swap and while doing so a 160 thermostat... Car stays 165 on interstate and comes and goes warmer at red lights and stuff. Ok cool.. the tune has it marked as a 160 thermostat so no codes from it not getting to full temp/190 and the fans are adjusted as well.
BUT THE TACK. I keep it in sport mode most the time and it shows the red line where it changes when cold. And this also moves where the factory shift lights come on... the car at normal temp is now 165. The tach and shift lights are messed up thinking the car is cold.. so is there a fix somewhere else in the tune? Or do I just have to go back to factory thermostat?
BUT THE TACK. I keep it in sport mode most the time and it shows the red line where it changes when cold. And this also moves where the factory shift lights come on... the car at normal temp is now 165. The tach and shift lights are messed up thinking the car is cold.. so is there a fix somewhere else in the tune? Or do I just have to go back to factory thermostat?
Last edited by mittens; Dec 18, 2017 at 09:22 AM.
Tech Contributor
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From: Charlotte, NC (formerly Endicott, NY)
What is your oil temperature when you are running at 165 on the interstate? There is a certain floor where most track drivers believe the oil isn't warm enough to support driving the car harder or going to extended WOT operation. GM may have set the tach warnings/settings to trigger off the oil temperature. We definitely know they put the car in limp home mode if oil temp exceeds 300+ degrees so they may have decided to use oil temp to advise the driver when the engine is warm enough to start pushing hard. You may have to run the car at speed in 4th gear instead of 6th or 7th to get the rpms higher to bring oil temperature up.
Bill
Bill
Last edited by Bill Dearborn; Dec 16, 2017 at 01:35 PM.
Le Mans Master
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From: Redmond WA
You've changed to a lower thermostat.
The engine coolant is now cooler (sometimes).
The engine oil is now cooler.
The tach will say shift earlier because it thinks the car isn't warmed up yet.
The engine coolant is now cooler (sometimes).
The engine oil is now cooler.
The tach will say shift earlier because it thinks the car isn't warmed up yet.
Thread Starter
Safety Car
Joined: Nov 2005
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From: Huntsville Alabama
I am fully aware of why the car is doing it. It’s cooler and the car is acting like it’s cooler.. My question is, is there a way to adjust this part? Just like you can adjust the temp the ECU looks for it to reach as full operating temp? and to not toss a code that it won’t warm up.
Which is set and why no codes on my car... and the fans work as well. But will the tach and shift lights always be wrong?
Oil temps 170 on highway. When Car is 165. So oil is warm enough to do its job.
Which is set and why no codes on my car... and the fans work as well. But will the tach and shift lights always be wrong?
Oil temps 170 on highway. When Car is 165. So oil is warm enough to do its job.
Last edited by mittens; Dec 18, 2017 at 09:25 AM.
I'm Batman..
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From: Lehigh Acres FL
Tech Contributor
I am fully aware of why the car is doing it. It’s cooler and the car is acting like it’s cooler.. my question is, is there a way to adjust this? Just like you can adjust the temp for the code that it won’t warm up. Which is set and why no codes... and the fans. But will the tach and shift lights always be wrong?
Oil temps 170 on highway. When Car is 165. So oil is warm enough to do its job.
Oil temps 170 on highway. When Car is 165. So oil is warm enough to do its job.
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
I am fully aware of why the car is doing it. It’s cooler and the car is acting like it’s cooler.. my question is, is there a way to adjust this? Just like you can adjust the temp for the code that it won’t warm up. Which is set and why no codes... and the fans. But will the tach and shift lights always be wrong?
Oil temps 170 on highway. When Car is 165. So oil is warm enough to do its job.
Oil temps 170 on highway. When Car is 165. So oil is warm enough to do its job.
Honestly, I think the gains from a thermostat are chimerical and I'd put the factory one back in if it were me, but you can update the car to compenstate if you like.
Problem is, I don't know if the RPM shift decisions and that stuff are really controlled by the ECM or if it's the BCM or some other module (whatever is displaying the shift light, for example).
My guess is those assumptions about "how cold is too cold" are probably baked into the other modules. I doubt they're configurable by engine, but you never know.
In other words, I think it'll be a LOT of work to get everything to reflect your new operating parameters.
Last edited by davepl; Dec 17, 2017 at 11:58 AM.
I'm Batman..
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From: Lehigh Acres FL
Tech Contributor
Sure, fix the tune. You changed the thermostat without telling the car.
Honestly, I think the gains from a thermostat are chimerical and I'd put the factory one back in if it were me, but you can update the car to compenstate if you like.
Problem is, I don't know if the RPM shift decisions and that stuff are really controlled by the ECM or if it's the BCM or some other module (whatever is displaying the shift light, for example).
My guess is those assumptions about "how cold is too cold" are probably baked into the other modules. I doubt they're configurable by engine, but you never know.
In other words, I think it'll be a LOT of work to get everything to reflect your new operating parameters.
Honestly, I think the gains from a thermostat are chimerical and I'd put the factory one back in if it were me, but you can update the car to compenstate if you like.
Problem is, I don't know if the RPM shift decisions and that stuff are really controlled by the ECM or if it's the BCM or some other module (whatever is displaying the shift light, for example).
My guess is those assumptions about "how cold is too cold" are probably baked into the other modules. I doubt they're configurable by engine, but you never know.
In other words, I think it'll be a LOT of work to get everything to reflect your new operating parameters.
Le Mans Master
Joined: May 1999
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From: Windermere FL
FWIW, I first tried a 180 stat, and now I am running a 170 stat.
As the others have stated, unless you are willing to do a tune, and void your power train warranty, the fans will only come on above 190, so in traffic and hot weather, your engine will not run much cooler.
But I did not experience any of the above described issues. No codes, no messages, no warm up issues.
As the others have stated, unless you are willing to do a tune, and void your power train warranty, the fans will only come on above 190, so in traffic and hot weather, your engine will not run much cooler.
But I did not experience any of the above described issues. No codes, no messages, no warm up issues.
Last edited by Flame Red; Dec 17, 2017 at 12:47 PM.
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Thread Starter
Safety Car
Joined: Nov 2005
Posts: 4,386
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From: Huntsville Alabama
While I appreciate responses some of the responses are like they did not read the thread.
Where is this adjusted? The tune has the thermostate peramiroer set to 160. That’s why no codes as I stated before. And the car is tuned I am not worried about a warranty I just finished a cam install and DOD delete... so far from that.
So if you have lower thermostat, and your tach does not show it being cold. Please let me know how and where to adjust. Because the normal spot is done already and yet Car thinks it’s cold
Where is this adjusted? The tune has the thermostate peramiroer set to 160. That’s why no codes as I stated before. And the car is tuned I am not worried about a warranty I just finished a cam install and DOD delete... so far from that.
So if you have lower thermostat, and your tach does not show it being cold. Please let me know how and where to adjust. Because the normal spot is done already and yet Car thinks it’s cold
Last edited by mittens; Dec 17, 2017 at 04:57 PM.
I'm Batman..
Joined: Apr 2014
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From: Lehigh Acres FL
Tech Contributor
While I appreciate responses some of the responses are like they did not read the thread.
Where is this adjusted? The tune has the thermostate peramiroer set to 160. That’s why no codes as I stated before. And the car is tuned I am not worried about a warranty I just finished a cam install and DOD delete... so far from that.
So if you have lower thermostat, and your tach does not show it being cold. Please let me know how and where to adjust. Because the normal spot is done already and yet Car thinks it’s cold
Where is this adjusted? The tune has the thermostate peramiroer set to 160. That’s why no codes as I stated before. And the car is tuned I am not worried about a warranty I just finished a cam install and DOD delete... so far from that.
So if you have lower thermostat, and your tach does not show it being cold. Please let me know how and where to adjust. Because the normal spot is done already and yet Car thinks it’s cold
If YOU tuned the car, well then that I can understand if you are asking because you don't know where it is. I don't officially remember where the setting is, just that I am pretty sure its there. Like you, I'd have to dig through HPT looking for it..
Ant
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From: Albuquerque NM
Simmer down, Mittens. Im not trying to pick a fight, but go back and reread your posts. You ask "CAN this be adjusted?" Not, "Exactly where do I go in the tune to change this?". I know the car is tuned, you specified this. I did not see you answer this so I will ask again, who tuned the car? You probably need to have your tuner sift through the billion settings in the tune to see where it needs to be changed.
If YOU tuned the car, well then that I can understand if you are asking because you don't know where it is. I don't officially remember where the setting is, just that I am pretty sure its there. Like you, I'd have to dig through HPT looking for it..
Ant
If YOU tuned the car, well then that I can understand if you are asking because you don't know where it is. I don't officially remember where the setting is, just that I am pretty sure its there. Like you, I'd have to dig through HPT looking for it..
Ant
Thread Starter
Safety Car
Joined: Nov 2005
Posts: 4,386
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From: Huntsville Alabama
I did not tune it a long time tuner and Friend did Clyde Carlson. He is great on LS stuff but the limited amount of E92 cars under his belt so its a little new. So while I am not tuning it I am asking IF and where it can be found.
My response was not to you, but more so the guy that stated you have to be willing to loose your warrenty....... like WTF read man Cam, tuned, all kinds of other stuff going on here, and he like warrenty........
My response was not to you, but more so the guy that stated you have to be willing to loose your warrenty....... like WTF read man Cam, tuned, all kinds of other stuff going on here, and he like warrenty........
Le Mans Master
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From: Redmond WA
I'd help you out but all I can do is proffer that it might not all be in the tune. Imagine the engine broadcasts on the CAN bus that it's at 5400rpm. The dash sees that packet. Should it turn on a shift light? Well, it knows the temp from broadcasts too, but how cold is too cold?
WHAT DEFINES WHEN THE SHIFT LIGHT SHOULD COME ON?
Is that up to the dash? Unless there are proprietary PIDs out there for the ECM to communicate the shift windows, I think its up to the dash, not the tune.
Last edited by davepl; Dec 18, 2017 at 12:11 PM.
Thread Starter
Safety Car
Joined: Nov 2005
Posts: 4,386
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From: Huntsville Alabama
That's right, don't take any guff from these strangers. You demand the help you deserve! Tell 'em who's boss!
I'd help you out but all I can do is proffer that it might not all be in the tune. Imagine the engine broadcasts on the CAN bus that it's at 5400rpm. The dash sees that packet. Should it turn on a shift light? Well, it knows the temp from broadcasts too, but how cold is too cold?
WHAT DEFINES WHEN THE SHIFT LIGHT SHOULD COME ON?
Is that up to the dash? Unless there are proprietary PIDs out there for the ECM to communicate the shift windows, I think its up to the dash, not the tune.
I'd help you out but all I can do is proffer that it might not all be in the tune. Imagine the engine broadcasts on the CAN bus that it's at 5400rpm. The dash sees that packet. Should it turn on a shift light? Well, it knows the temp from broadcasts too, but how cold is too cold?
WHAT DEFINES WHEN THE SHIFT LIGHT SHOULD COME ON?
Is that up to the dash? Unless there are proprietary PIDs out there for the ECM to communicate the shift windows, I think its up to the dash, not the tune.
Back on topic, that's also part of the question IS it changeable, do others with a lower temp state have this issue or is it fixed somehow. If its in the BCM or something that just reads the temp form the ECU, then it make not be fixable. or like you said maybe the dash just reads that PID and does what its told...
Just would like a answer. and one guy above saying at 165 his is normal... so that seems its a fixable issue, just not sure how or where.
I'm Batman..
Joined: Apr 2014
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From: Lehigh Acres FL
Tech Contributor
I did not tune it a long time tuner and Friend did Clyde Carlson. He is great on LS stuff but the limited amount of E92 cars under his belt so its a little new. So while I am not tuning it I am asking IF and where it can be found.
My response was not to you, but more so the guy that stated you have to be willing to loose your warrenty....... like WTF read man Cam, tuned, all kinds of other stuff going on here, and he like warrenty........
My response was not to you, but more so the guy that stated you have to be willing to loose your warrenty....... like WTF read man Cam, tuned, all kinds of other stuff going on here, and he like warrenty........
Thread Starter
Safety Car
Joined: Nov 2005
Posts: 4,386
Likes: 942
From: Huntsville Alabama
Same problem, and we checked every where we could in HP tuners...
Mechanical thermostat is set to 160
The desired coolant temp table to 160
The fuel cut off start up modifier is also adjusted down to the proper intake temps as well.. but same result (even tried the whole table at 6800 once just for good measure)
Is this nor possible to fix in the tune, if not will swap back to the stock one.
Mechanical thermostat is set to 160
The desired coolant temp table to 160
The fuel cut off start up modifier is also adjusted down to the proper intake temps as well.. but same result (even tried the whole table at 6800 once just for good measure)
Is this nor possible to fix in the tune, if not will swap back to the stock one.
Last edited by mittens; Dec 26, 2017 at 09:17 AM.
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
Same problem, and we checked every where we could in HP tuners...
Mechanical thermostat is set to 160
The desired coolant temp table to 160
The fuel cut off start up modifier is also adjusted down to the proper intake temps as well.. but same result (even tried the whole table at 6800 once just for good measure)
Is this nor possible to fix in the tune, if not will swap back to the stock one.
Mechanical thermostat is set to 160
The desired coolant temp table to 160
The fuel cut off start up modifier is also adjusted down to the proper intake temps as well.. but same result (even tried the whole table at 6800 once just for good measure)
Is this nor possible to fix in the tune, if not will swap back to the stock one.
Thread Starter
Safety Car
Joined: Nov 2005
Posts: 4,386
Likes: 942
From: Huntsville Alabama
so what Therm are you running and it doe snot do this? It seems watching a scanner. if the car hits 175... it thinks thats fully warm tach and Shift lights wise... its below that when this issues shows its face.
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
I run a 160 stat myself. I'll have to pay attention next time I take it out and see where the temp is when the bar goes away.