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> 2.0/ four question, question about sensor on number 3 cylinder head
pete-stevers
post Jun 13 2006, 06:15 PM
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What is this sensor used for??
what should it be conected to??
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SLITS
post Jun 13 2006, 06:19 PM
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Sensor is the CHT (Cylinder Head Temp). Sends signal which affects mixture to brain.......It connects to the same colored wire on the FI harness.
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pete-stevers
post Jun 13 2006, 06:27 PM
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so its a fuel injection sensor?
is it deleted if running carbs.....
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Mueller
post Jun 13 2006, 07:00 PM
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QUOTE(pete-stevers @ Jun 13 2006, 05:27 PM) *

so its a fuel injection sensor?
is it deleted if running carbs.....


correct, FI only....I guess you "could" use it for a temp sensor if you had a corresponding gauge (my laptop read this sensor when it's plugged in) , but you are better off using a sensor that gets mounted under a sparkplug for that....toss it or give it to someone with FI to test it or play with...
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pete-stevers
post Jun 13 2006, 07:15 PM
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thanks muller (IMG:style_emoticons/default/boldblue.gif)

pretty soon (IMG:style_emoticons/default/driving.gif)
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Mueller
post Jun 13 2006, 07:17 PM
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QUOTE(pete-stevers @ Jun 13 2006, 06:15 PM) *

thanks muller (IMG:style_emoticons/default/boldblue.gif)

pretty soon (IMG:style_emoticons/default/driving.gif)


no problem, but I thought you had a /6????
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bd1308
post Jun 13 2006, 07:19 PM
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nope...the sensor's operability range is only good from a "cold" condition to a "warm AKA operating temp" range....

anything above, from like let's say 275 to 400+ I wouldnt think it would accurately measure...since at operating temp, the resistance is only around 150 or so ohms right?

b
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pete-stevers
post Jun 13 2006, 07:26 PM
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its my brother Greg's car...(pete-greggers)
the six got its first breath of life late last nite
yup EEEETS AHHHHHLIVE too!
greg is replacing his old tired motor with the 2.0 we pulled out of mine....
and just put fresh heads on....
how's that for trouble
two brothers
two teeners
.....eight jackstands
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Mueller
post Jun 13 2006, 07:34 PM
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QUOTE(bd1308 @ Jun 13 2006, 06:19 PM) *

nope...the sensor's operability range is only good from a "cold" condition to a "warm AKA operating temp" range....

anything above, from like let's say 275 to 400+ I wouldnt think it would accurately measure...since at operating temp, the resistance is only around 150 or so ohms right?

b


sorry, you got it wrong...it's linear..as for being used with FI, the brain sees it as an on/off switch, but in reality it is not..

oh your brother!?!?!?

that is too cool (IMG:style_emoticons/default/drunk.gif)
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bd1308
post Jun 13 2006, 07:38 PM
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so what's the effective range of this sensor?

b
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Mueller
post Jun 13 2006, 07:47 PM
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QUOTE(bd1308 @ Jun 13 2006, 06:38 PM) *

so what's the effective range of this sensor?

b


i've only read mine from ambient temp (about 70°) to operating temp (I want to say 300°, but it's been awhile since I've looked at), I'm sure it'll operate at lower and higher temps
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bd1308
post Jun 13 2006, 07:47 PM
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Normal Value(s):
* 0 280 130 003 and 0 280 130 012: about 2.5 K ohms at 68 deg. F, less than 100 ohms with hot engine.
* 0 280 130 017: about 1.3 K ohms at 68 deg. F, less than 100 ohms with hot engine.
* See Notes section below for more data on the resistance vs. temperature values of these sensors.


lets define a "hot" engine as one operating at idle head temp. Show me where there is room for any ADDITIONAL scale? 100 ohms isnt much.

b
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Mueller
post Jun 13 2006, 08:10 PM
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QUOTE(bd1308 @ Jun 13 2006, 06:47 PM) *

Normal Value(s):
* 0 280 130 003 and 0 280 130 012: about 2.5 K ohms at 68 deg. F, less than 100 ohms with hot engine.
* 0 280 130 017: about 1.3 K ohms at 68 deg. F, less than 100 ohms with hot engine.
* See Notes section below for more data on the resistance vs. temperature values of these sensors.


lets define a "hot" engine as one operating at idle head temp. Show me where there is room for any ADDITIONAL scale? 100 ohms isnt much.

b


well, you can have a resistance of Less than 100 ohms you know.....i'm sure (I know for a fact) that if you take one of the CHTs mentioned and put it in cold water, it'll read more than the 2.5K or 1.3K listed or if you heat up more than what the standard operating temp is, the number will go down)..those number posted are what the ECU expects to see or what can be easily checked
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bd1308
post Jun 13 2006, 08:15 PM
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even if that is true, it has also been noted that the best and accurate measurement of CHT would be measured at the #3 plug, rather than a predrilled socket just forward of the cylinder.

Do what ya'll want, I'll stick with my CHT guage. The range of the stock sensor isnt designed for complete analysis of CHT on the right bank, it was used just for warm-up mix control.

b
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Mueller
post Jun 13 2006, 08:35 PM
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QUOTE(bd1308 @ Jun 13 2006, 07:15 PM) *

even if that is true, it has also been noted that the best and accurate measurement of CHT would be measured at the #3 plug, rather than a predrilled socket just forward of the cylinder.

Do what ya'll want, I'll stick with my CHT guage. The range of the stock sensor isnt designed for complete analysis of CHT on the right bank, it was used just for warm-up mix control.

b


listen numbnuts, did you read my post where I said pretty much just that?? (IMG:style_emoticons/default/biggrin.gif)

QUOTE
correct, FI only....I guess you "could" use it for a temp sensor if you had a corresponding gauge (my laptop read this sensor when it's plugged in) , but you are better off using a sensor that gets mounted under a sparkplug for that....toss it or give it to someone with FI to test it or play with...
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bd1308
post Jun 13 2006, 08:38 PM
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I just dont want to give anybody the impression by suggesting that the stock FI CHt sensor could be used to accurately meausure head temperatures....

although its easy to measure head temps when your car is up on jackstands!

b
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Mark Henry
post Jun 13 2006, 08:48 PM
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GBallantine
post Jun 14 2006, 07:10 AM
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I used a VDO CHT gage with the ring connector that fits under the spark plug. It's a giant PITA and gets completely chewed up on the tin and makes spark plug removal difficult. In fact the sensor ring becomes entangled in the threads of the plug. It did work well on my 2270 race motor giving readings of 325 to 350 degrees`. I tried relocating it in the original FI CHT hole but no go/ no reading.

GB
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DNHunt
post Jun 14 2006, 07:31 AM
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I have both on my car. The CHT under #3 plug is a thermocouple. 2 different metals that generate a small current when heated. The stock CHT has decreasing resistance with increasing temperature and is linear. It works well for warm up enrichment (what it was designed to do) and both sensors agree pretty well until the car is warm. After 300 degrees the stock sensor doesn't have enough resolution to be of much good for a gauge. With carbs rip the little POS out and try to sell it at a swap meet.

Dave
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rhodyguy
post Jun 14 2006, 09:41 AM
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with carbs (that's what your bro is doing, right?), just unplug it, leave it alone.

k
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