gerry

I own a 1989 dual fan 350 5.7 iroc-z. I want to know where the coolant temp sensor, coolant temp sending unit and the fan switch are located in my car. Other than the above mentioned sensors are there any more coolant related sensors
in my iroc-z that I need to know of. If so, where are they located? I need help! None of the mechanic shops (pep boys, firestone etc.) around my town seem to know anything about where they go. On seperate occasions a fan switch was installed on the drivers side in between the 1st and 3rd cylinders. I have recently found out that the switch actually goes on the passenger side in between the 6th and 8th cylinders. Is this true? A mechanic at another shop used an infrared tool to get an actual temp reading. The temp is off by 30*. He suggested that I get new temp gauge. I replaced it with a new one, the guage is still reading 30* higher than what the temp actually is. What can I do? I'm going to have a jet performance low temp fan switch installed. I need to know exactlly where it goes. Any help would be appreciated.

Thanks,
Gerry

P.S. Any help would be greatly appreciated.

[This message has been edited by gerry (edited November 21, 2001).]

[This message has been edited by gerry (edited November 21, 2001).]

[This message has been edited by gerry (edited November 21, 2001).]

86TpiTransAm

The coolant temp sensor that the computer uses to go from open loop to close loop operation is located on the very front of your intake. The sensor that is located between cylinder #1 and #3 is NOT the fan switch.... that sensor is the one that goes to the gauge inside the car and tells you your eng. temp. The fan switch, unless I'm mistaken, does indeed go in the passenger side head between the #6 and #8 cylinder. The back side of the passenger side head is a complete bitch to get to. For $20 at my local parts store I bought an adjustable fan switch that I mounted on the firewall with my relays. This fan switch utilizes a temp probe that you attach to your radiator and the wire going to the fan(s) that originally went to the stock fan switch is used as well. I wouldn't give this fan switch up for nothing. I can adjust when my fan kicks on and off with just the turn of a **** which is very nice when I switch to cooler or hotter thermostats.

86irocL98

correction, the thing between cylinder 1 and 3 is a water temp sending unit...a sensor needs 2 wires to operate, if you look, the sending unit only has 1 wire.

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-mark
86 iroc
-comp cam .444 lift with manley valve springs
-comp magnum 1.5 rockers
-tpis adj. fuel pressure regulator
-tpis airfoil
-homemade ram air with modified maf
-k and n
-3 inch random cat, 3 inch intermediate pipe and flowmaster muffler
-msd cap adapt with blaster gm coil, msd 6al and accel 8.8 wires
-ads strip chip
-console megashifter
-phantom gauges
-stereo system
-91 rs ground effects...soon

Moulder

I've got an L69 and I'm having the same problem. There is a 'sensor' for the compooter, a sending unit for the dash gauge, and a switch for the fan.
From what I can tell, the sensor is on the thermostat housing, the sending unit is between #1&3 (just below exh manifold), and there is a round plug (like the one on the thermohousing) between #6&8.
So is this is the fan switch? If so, where is my knock sensor?
Brent Pedersen

deadbird

The one in the head on the pass side is the fan switch. The knoch sensor is on the same side in the block right next to the starter with 1 wire comming from it.

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Tim Burgess

All "senders" are actually "sensors", and must have at least two wires connected to them internally to perform any useful function. In my opinion, the terms sender and sensor are interchangable - as is the case with the terms "condenser" and "capacitor". In some cases, one of the internal sensor wires is attached to the body of the sensor, in which case connects that sensor wire to the chassis ground circuit. Body grounded sensors are generally used in systems not requirinig precision voltage measurement.

One other temperature sensor in your '89 is the intake air temperature (IAT) sensor. It is located on the underside of the plenum, toward the rear. At some time, you may want to relocate it to the air box, such that its reading will be more accurate - not affected by the high temperature of the plenum. Also note that factory temperature gauge is not linear. In other words, if the gauge needle is midway between the 100 & 220 marks, the temperature is not [(220-100)/2 + 100]=160; it's actually more like 190.

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Tim

1992 Z28, 305 TPI 5 speed, 12.0 sec @ 114.8 mph

1984 Berlinetta 305 TPI Auto, 13.8 sec @ 99.7 mph