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Thanks to the incredible TLC that the previous owner gave my Camaro (I'm being very sarcastic), it has all sorts of wiring issues. I've had to pull over and shut the car off 4 times now because it's overheating. Every time, the issue is fixed my messing with the fan relay located at the driver side firewall (single fan system), but there never seems to really be any real solid way to fix it but it seems to have to do with the connection between the relay and the connector, it goes out randomly and sometimes I'll have to mess with it for 10 minutes before it just kicks back on. I should also mention that I there is a 4-way splice going into the relay, which makes it kinda hard to follow a wiring diagram because it doesn't explain it very well and the wires aren't all the same color as they originally were. The fan is also always on when the car is on, it doesn't go by a temp reading. How would I get it to go off of temp, and does anyone know if this would more likely be an issue with the relay itself or the connector that goes into it?
The fan is controlled bye the relay getting grounded bye the cylinder temp switch. The switch is located in the passengers side head between cylinder 6 & 8.
The grand national sw555 head switch is a better choice for lowered on and offs.
If you need the coolant temp pigtail it often gets damaged due to heat and age. https://m.ebay.com/itm/GM-Knock-Sens...UAAOSwNSxVNx-6 http://tpiparts.net/inc/sdetail/761/4572
Ac delco 15-8240 relay and pigtail PT1115.
What difference does the amperage make in a relay? I O'Reilly's has 15 and 30 amp relays, what effect would each have on the performance of the fan? also, the motor in my car isn't the stock 305, its a 350 out of a chevy truck. Would it still have the same switch and switch location?
It should have the fan switch located in the same spot. I would use a 30 amp relay startup amps can be high. A spdt relay would work fine but are not weather proof like later model gm relays/ pigtails.
Last edited by Tuned Performance; May 18, 2018 at 02:13 PM.
I would pick up a new relay at the Auto parts store and some terminal connectors and wire it in . Parts less than 20. bucks, a lot less. Which actually I did when I had this same problem on my single fan 86
I'm looking at 5 terminal relays made for cooling fans, they've got ones nearly identical to the one that's in my car right now for about $12, it's a 30 amp. I'm hoping the connectors will be the same. The fan being on whenever the key is on wouldn't cause any issues, right?
the block sensor is the ground when it hits it's trigger temp it will ground the relay which will close the relay allowing power to flow from 30 to 87 and to the fan.