Coolant sensor or Knock sensor??
05-11-2002, 10:45 PM
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Coolant sensor or Knock sensor??
So long story short. My fan wasn't working, I've bought my fan relay and what I thought was my coolant sensor. The sensor the parts store and Chilton's manual show a two wire connector/plug. I look under my car and find a 1 wire connector with a 1 or so inch larger cylinder on the sensor " I think this is my knock sensor" on the pass side block and a one wire sensor on my driver side head. I thought the drivers side head has the coolant sensor. I have a 91 1LE or "L98" engine. Is this driver side sensor the coorect one? Do I need to return the sensor I bought and get a 1 wire??
05-11-2002, 11:13 PM
#2
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Car: 87 Formula/ 00 Xtreme
Engine: TPI 305/ v6
Transmission: struggling t-5/ 4l60E
Axle/Gears: 3.08/ 3.23
I wish this subject would become a sticky or something...
It's not your fault bud..n/m me ramblings....
TPI (dual) fans are controlled
1) main fan (side varies depending on OEM wiring I guess but, normally I think it is the drivers side) by the ECM which switches the fan on (controlled ground) around the 220° range ± a few degrees. And the primary also comes on when the A/C is turned on (A/C pressure switch sends a 'request' to the ECM and the ECM grounds the fan relay)
2)There is a fan switch (color might vary but was black in my case) in the pass side head (not block) that controls the 2ndary fan (2nd fan comes on at 238°).
On a TPI, the coolant sensor for the ECM is in the base of the TPi intake (yellow wire & black wire (2 wires total)).
2 primary reasons of the fan(s) would not working, relay is bad, fan motor is shot.
The knock sensor (white wire) is in the lower part of the pass side block foward of the starter.
It's not your fault bud..n/m me ramblings....
TPI (dual) fans are controlled
1) main fan (side varies depending on OEM wiring I guess but, normally I think it is the drivers side) by the ECM which switches the fan on (controlled ground) around the 220° range ± a few degrees. And the primary also comes on when the A/C is turned on (A/C pressure switch sends a 'request' to the ECM and the ECM grounds the fan relay)
2)There is a fan switch (color might vary but was black in my case) in the pass side head (not block) that controls the 2ndary fan (2nd fan comes on at 238°).
On a TPI, the coolant sensor for the ECM is in the base of the TPi intake (yellow wire & black wire (2 wires total)).
2 primary reasons of the fan(s) would not working, relay is bad, fan motor is shot.
The knock sensor (white wire) is in the lower part of the pass side block foward of the starter.
05-12-2002, 03:57 PM
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Thanks for info, 1 more question
So, now that I know what's what. What is the single wire connnector on the driver side?? Almost opposite location of knock sensor but on the head under the exhaust manifold??Thanks again for any info.
05-14-2002, 04:05 PM
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Car: '92 Z28; Dk Teal; Her Pkg
Engine: 305
Transmission: Richmond 6 Spd
Axle/Gears: Moser 9", Detroit Locker, 3.70
A few corrections to the '90 - '92 dual fan operation: The primary fan is on above 226 F & off below 221 F. If the A/C is on (A/C request input to the ECM from the A/C select switch), the ECM turns the primary fan on if the above engine temperature conditions are met, or if the speed of the car is below about 30 mph. For the secondary fan, in addition to the switch in the pass side cyl head that turns the secondary fan on above 238 F, there is an A/C pressure switch in the liquid line that turns the secondary fan on when the R-12 pressure exceeds 232 psig.
05-18-2002, 04:08 PM
#6
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thats alot of temperature, howcome they programmed them to come on so late ? damn..
good luck
good luck
05-19-2002, 06:26 PM
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Car: 1991 T/A - Sold (sniff) 1980 T/A Pa
When my temp sensor went bad I bought a new one, got home, and proceeded to remove the knock sensor and give myself a hot coolant bath.
The temp sensor is real high on the block between #6 and #8 spark plugs. The knock sensor is down low by the oil pan.
If I remember correctly the temp sensor is 1 wire.
Chris G
The temp sensor is real high on the block between #6 and #8 spark plugs. The knock sensor is down low by the oil pan.
If I remember correctly the temp sensor is 1 wire.
Chris G
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