Differences in Temperature Readings

huntsg

Active Member
Joined
Aug 10, 2009
Anybody seen this before? Scanmaster G temperature reading is 155 F. The temperature reading in my center console pod is 195 F. I expect there to be a difference between the two, but 40 degrees?
 
Scanmaster G just displays the ECM data, what kind of gauge is in your console pod?

the sensors are fairly close to each other, so I would not expect much of a temperature difference.

Bob
 
it's an Auto Meter Pro Comp Ultra Lite 100F to 250F gauge. I replaced the Auto Meter sensor about 2 months ago with no change in results.
 
Pretty sure I did. Either that or thread sealer.

Sent from my SAMSUNG-SM-G925A using Tapatalk
 
"If" the sensor gets its' ground through the body, the tape may compromise the ground side.
Not sure if that's the issue, but that what I would look at.

If one is 155F and the other 195F; Which one do you think is closer to the truth?
What is each reading, including IAT, on a cold engine?
 
am pro ULite doesnt use ground for sensor nor does the oe clt sensor . the AM pro ul gauges i use in my vehicles are 2 wire 1/8npt sensors and they come with a prewired harness from sensor to gauge with enough wire that connections should be as from factory with no cuts
if after sitting overnight (not in sun ) the IAT and CLT say the same on SM then good chance the AM gauge is wrong
you could also get a thermal temp gun and shoot the intake near clt sensor and see which one is true

where did you install the Gauge sensor ? if its in the block drain between cylinders you could be getting a bad reading compared to the intake runner
 
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am pro ULite doesnt use ground for sensor nor does the oe clt sensor . the AM pro ul gauges i use in my vehicles are 2 wire 1/8npt sensors and they come with a prewired harness from sensor to gauge with enough wire that connections should be as from factory with no cuts
if after sitting overnight (not in sun ) the IAT and CLT say the same on SM then good chance the AM gauge is wrong
you could also get a thermal temp gun and shoot the intake near clt sensor and see which one is true

where did you install the Gauge sensor ? if its in the block drain between cylinders you could be getting a bad reading compared to the intake runner
Good suggestions. Once I get back home from San Diego I'll do both of those tests.
 
External gauge is reading right as it returns from the radiator. ECM reading from top of the intake... mine SM reads a bit hotter than the external.
 
am pro ULite doesnt use ground for sensor nor does the oe clt sensor . the AM pro ul gauges i use in my vehicles are 2 wire 1/8npt sensors and they come with a prewired harness from sensor to gauge with enough wire that connections should be as from factory with no cuts
if after sitting overnight (not in sun ) the IAT and CLT say the same on SM then good chance the AM gauge is wrong
you could also get a thermal temp gun and shoot the intake near clt sensor and see which one is true

where did you install the Gauge sensor ? if its in the block drain between cylinders you could be getting a bad reading compared to the intake runner

Car was in the garage all week. Turned the key on and the Scanmaster read Coolant 68 and Air Temperature 79. The sensor for the gauge is in the intake right here in the picture.
20180804_133500.jpg
 
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