rottweiler68

Found this hanging, appears to be broken off. It's bottom of passenger side near rear motor mount on '89 5.7

TTOP350

iTrader: (8)

secondary fan switch harness. It goes up between cyl 6 and 8 in the head.

rottweiler68

Thanks, going to try and track that part number down.

RunawayRadio

iTrader: (2)

Here you go:

https://www.rockauto.com/en/moreinfo...251414&jsn=506

rottweiler68

Awesome, thanks so much! Is this the same part number used for the knock sensor connector as well? I see it referenced as such elsewhere.

rottweiler68

And another dumb follow up question, sorry new to much of this, what is the connector to the right of the dangling fan harness wire that is connected properly in the pic?

Ghettobird52

if thats the 'secondary fan switch' whats the first....?

ploegi

Knock sensor.

rottweiler68

Thank you!

TTOP350

iTrader: (8)

ECM runs the primary fan from the cts info.
Since this is a 89 350 car it will have 2 fans, this switch (and A/C psi switch) run the secondary fan.

rottweiler68

I already have the 180* thermostat in so was thinking about going with the Hypertech 4028 switch to run a bit cooler. Does sound correct?

TTOP350

iTrader: (8)

This may work as well
https://www.thirdgen.org/forums/engi...itch-part.html

Ghettobird52

Ok so on the single fan setups they just work off the coolant head switch right?

TTOP350

iTrader: (8)

I'm not well versed in single fan setups

rottweiler68

Does anyone have an actual pic of this sensor location that would be the same the '89 350? I though it was between plugs 6 and 8, but can not find it for the life of me. I have found the knock sensor from below, but should I be able to see the this fan sensor as well from the top or bottom?

Ghettobird52

If you still have the complete ac box and heater hosing along with smog equipment all intact, it can be pretty hard to see it from up top. But its right there on the head between 6&8. The electrical connector might be snapped throwing you off.

https://www.thirdgen.org/forums/cool...an-switch.html see thread for pic.

Tuned Performance

iTrader: (92)

henryd3

iTrader: (128)

It's in the same spot(with the head turned around for the other side) as the sensor for the temp gauge on the driver side

rottweiler68

Crazy! I must be missing something it simply as Ghettobird alluded too because of being broken off. But I thought this secondary was at the rear of the head by 6 & 8, my gauge temp sensor is at the front of the drivers side, between 1 and 3.

rottweiler68

I also found posts with some accessing it from the underside. "This little switch is located in a hard-to-reach location on this Third-Generation Camaro. In other vehicles it may be easily accessible. The sensor is located on the passenger side of the engine, just below the heat shield connected to the block."

Time for a break

Ghettobird52

ok wow yeah that looks like the location, but that looks like someone just plugged it?

rottweiler68

Sorry was editing that post with picture, but yes you are right, they probably got tired of losing coolant and plugged it. That's why i'm stumped lol.

TTOP350

iTrader: (8)

Looks like factory it could be factory paint down in the plug, your car does have dual fans right? Or its just been plugged due to leak, breakage or during a rebuild. Either way, if you have dual fans, put the switch in that spot.

rottweiler68

Yes I do have the dual fans so will attempt to unscrew whatever it is that is in there.

rottweiler68

Is there a simple way to tap the second fan into the first (not sure if that's the term) but so that the second fan would run whenever the primary ran? Can't hurt to have this type of setup can it?