Cooling Fan Relays

Pishaw

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I have a 2004 Grand Prix GT2. It has 210,000 miles on it. However, the engine compression checks to within 5% on all six cylinders. There is no rust anywhere. It makes no valvetrain noise. At all. No piston slap when it's cold. It doesn't burn any oil. It runs great. I paid two grand for it, and have replaced headlight assemblies, front struts, rear stabilizer bar, drivers side rear wheel bearing, wires plugs and coil packs, and the trunklid struts. Everything on the car works, except for the cruise control. But since I don't use it, I haven't bothered to check the fuse. It gets 25 average MPG, in town and rural highway. It still needs rear struts, and probably various suspension bushings. But it doesn't need them bad enough that I am buying parts right now. I'll get to it.

This is one of the most enjoyable cars I have ever owned. I am of an age that I have owned a '73 Trans Am, a '72 Chevelle, and a 1969 Mach 1 351 four speed. I f$%king love this car. It handles great, has more than enough power, and it has style and grace, if you can relate to that. I have about $2,700 in it. I have put 14,000 miles on it so far, with no problems. Except...

I am finally getting around to fixing the little stuff, like the radiator cooling fans that run all the time on high but I can't hear them in the car. Both ran on high all the time. So I removed relays #42 and #43 from the underhood fuse block. I replaced the #42 (fan1) relay, and left the other one out. Now the drivers side cooling fan runs on low speed and the other fan doesn't run at all. I'm fine with that for now. The temp sensor must still be good, because the temp gauge is right on the money at 185, right? If the sensor were bad, the gauge would be inaccurate or non functional. And as the fans both run at both speeds, I would assume the grounds and wiring are solid, right? It can be nothing but a relay problem. Right?

I am a master of procrastination. Now that the car doesn't sound like a DC 8 taking off, and it and it definitely is not going to overheat, I am still operating it without relay #43 (fan 3). Here is my question: Will that break anything, running the car without a relay in the block? The check engine light came on when I ran it without both relays, and the code said fan relay #1 was missing. So I bought a new one, and all has been well.

Should I be replacing the rest of the fan relays tomorrow, or can I get around to it when I feel like it?
 
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Did you have a check engine light on when both fans were running?
185 is cold and if the computer suspects any kind of cooling system issue the fans will run.
 
From what I have read, replacing the 195 thermostat with a 180 was something people did for some reason. But it runs at a constant 185, so I'll leave it alone for now. The only time the CE light came on was when relays 1 & 3 were both out. The car doesn't like it when relay 1 is not installed. Apparently both fans running fast is something the car does when one or more relays, or the temp sensor, fail. The sensor seems good, as the gauge works correctly, so I started buying relays. Eventually I'll replace the other two relays, but for now it runs fine.

One other question I had was that when the car is cold (first start of the day) it idles at 1400 RPM for about 3 minutes. That seems a bit excessive to me. Is this a common thing, or should I worry about it?
 
From what I have read, replacing the 195 thermostat with a 180 was something people did for some reason. But it runs at a constant 185, so I'll leave it alone for now. The only time the CE light came on was when relays 1 & 3 were both out. The car doesn't like it when relay 1 is not installed. Apparently both fans running fast is something the car does when one or more relays, or the temp sensor, fail. The sensor seems good, as the gauge works correctly, so I started buying relays. Eventually I'll replace the other two relays, but for now it runs fine.

One other question I had was that when the car is cold (first start of the day) it idles at 1400 RPM for about 3 minutes. That seems a bit excessive to me. Is this a common thing, or should I worry about it?
Cold idle sounds correct
Assuming the relays don't solve the issue you would need an advanced scan tool to find out why they run at 185, they should not be coming on till over 200.
 
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