ECT vs. Temp Guage
Thread Starter
Teching In
Joined: Dec 2005
Posts: 15
Likes: 0
ECT vs. Temp Guage I bought a Diablo programmer and while viewing live data it says my ECT is (example) 170 (have a 160 thermostat installed) however my temp guage in the car says 210.
Is the ECT tied to the coolant temp in the radiator and the cars temp guage tied to the head temp?
Also, when adjusting my setting for the fans on/off is that based on the ECT or the cars temp guage?
I know...alot of questions but this is my first LS1 and and I feel like I'm learning cars all over again
Is the ECT tied to the coolant temp in the radiator and the cars temp guage tied to the head temp?
Also, when adjusting my setting for the fans on/off is that based on the ECT or the cars temp guage?
I know...alot of questions but this is my first LS1 and and I feel like I'm learning cars all over again
It depends on what year your car is. Only 1998 Models had a real temp gauge in the gauge cluster, 1999-2002 had what is termed as an Idiot gauge. If functions just like and idiot light, but instead of turning on a light, it moves a needle to three different positions (cold (below 160), warm (range between 170-220), hot (anything over 220)). If you have a newer model, then do not base any temp reading from your gauge cluster, rather use a scanner to check the true temp of the engine ... the ECT is/should be the engine/coolant temp.
Thread Starter
Teching In
Joined: Dec 2005
Posts: 15
Likes: 0
Originally Posted by Flame Throwing SS
It depends on what year your car is. Only 1998 Models had a real temp gauge in the gauge cluster, 1999-2002 had what is termed as an Idiot gauge. If functions just like and idiot light, but instead of turning on a light, it moves a needle to three different positions (cold (below 160), warm (range between 170-220), hot (anything over 220)). If you have a newer model, then do not base any temp reading from your gauge cluster, rather use a scanner to check the true temp of the engine ... the ECT is/should be the engine/coolant temp.
Could I use the temprature sending unit from a 98 in my 2000 to make the guage work properly or should I just disreguard it all togather and get a aftermarket mechanical guage and hook it up to the head?
BTW thanks everyone for your help...
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
nope...
98s = 3 wire temp sensor... 1 to PCM, other direct to gauge
99+= 2 wire.. no wire to gauge ... it's accurate to the PCM (if you use a data scanner it's accurate) but it gets dummied down somewhere between the PCM and the needle
if you want an accurate temp gauge that bad, easiest would prolly be to install an autometer coolant temp gauge... I think you can install it on the passenger side head (both heads have a spot for a temp sender I believe)
98s = 3 wire temp sensor... 1 to PCM, other direct to gauge
99+= 2 wire.. no wire to gauge ... it's accurate to the PCM (if you use a data scanner it's accurate) but it gets dummied down somewhere between the PCM and the needle
if you want an accurate temp gauge that bad, easiest would prolly be to install an autometer coolant temp gauge... I think you can install it on the passenger side head (both heads have a spot for a temp sender I believe)
Thread Starter
Teching In
Joined: Dec 2005
Posts: 15
Likes: 0
Originally Posted by horist
nope...
98s = 3 wire temp sensor... 1 to PCM, other direct to gauge
99+= 2 wire.. no wire to gauge ... it's accurate to the PCM (if you use a data scanner it's accurate) but it gets dummied down somewhere between the PCM and the needle
if you want an accurate temp gauge that bad, easiest would prolly be to install an autometer coolant temp gauge... I think you can install it on the passenger side head (both heads have a spot for a temp sender I believe)
98s = 3 wire temp sensor... 1 to PCM, other direct to gauge
99+= 2 wire.. no wire to gauge ... it's accurate to the PCM (if you use a data scanner it's accurate) but it gets dummied down somewhere between the PCM and the needle
if you want an accurate temp gauge that bad, easiest would prolly be to install an autometer coolant temp gauge... I think you can install it on the passenger side head (both heads have a spot for a temp sender I believe)
So is it correct to say that the head temp is the same as the ECT? Sorry, a bit old school here and I like to know whats goin on with the motor. Is the same true for the oil pressure guage (that it is a dummy guage as well)?
Trending Topics
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
oil pressure is a real gauge... on F-Body's there's no PCM feed... it goes straight to the gauge cluster
I think that the coolant sensor plugs into one of the cooling passages in the head ... so it measures the Engine Coolant Temp not necessarily the cylinder head temperature
I think that the coolant sensor plugs into one of the cooling passages in the head ... so it measures the Engine Coolant Temp not necessarily the cylinder head temperature
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
See this link for sample schematic diagram showing temp and oil guages:
https://ls1tech.com/forums/showthrea...ighlight=gauge
https://ls1tech.com/forums/showthrea...ighlight=gauge
