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Discussion Starter #1
I already added the tranny aux radiator and flushed the tranny with all new fluid even replaced the pan with one that has a drain bolt.
Everything else has also been replaced. AC Delco 190 thermostat, AC Delco water pump, radiator is 2 years old. Fan Clutch is also new off the market. New CTS also. I tested the wires from the PCM to the relay 45 and fan harness and they show continuity. Using a OBD2 Autel I can read fan speed and it goes to 800 on the freeway. The fan seems to engage but when it goes hotter it doesn't seem to go faster. Truth be told I didn't check fan speed at higher temps. It gets up to 128 or 130 on a relatively short hill on the 405 at Sunset. I tested compression and it's at 205 on all. I used a vacuum gauge and it stays in the green. I tested the exhaust and the gauge showed 0 so no restriction from the cat. I flushed the radiator and filled it to specs.
The only thing I can think of is the speed of the fan. The 45 and 46 relays are side by side and one night the lights went out while on the freeway, and I know it's from the relay. I used the fog lights to the destination which was 2 minutes away and after shutting the car off and back on it was ok. I have a tendency to switch those 2 relays around so maybe that's why I sometimes get hot and sometimes not. On the relay number 4 contact that goes to the white wire on the fan harness shows ground only. I actually took out the relay and jumped 2 and 4 and the clutch got louder but not airplane loud.
on the tester.
Any advice would be appreciated.
 

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For the price of a couple of relays, I think I'd replace them.
 

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Are you using dexcool? If so you can pull the plugs and see if you have coolant stains which would indicate a a cracked head.
 

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Are you at a 50 / 50 mixture or protected to minus 34 below??? Is there any opem air space between the radiator and the fan(s)???
 

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Discussion Starter #6
I do have as close to 50/50 dex as humanly possible. as far as open air between the radiator and fan?! don't know what that means but yeah there is space for the fan to turn, and it has air all surrounded by a beautiful shroud , so I'd say it's opened but not. I know I will be looking for at least one relay probably both so I don't have to experiment.
 

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4.2 I assume.

Unfortunately 230 is kinda typical with the unbalanced cooling system they have. Its a tiny radiator and most of the fluid is in the hot block, not an even split. That is why it has the huge mechanical fan and not an electric one.
 

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Discussion Starter #8
I didn't use to get to 230 before. This happened only recently and it's not supposed to do it without load. I have tested it with Tech 2 and when I command the fan to raise the speed it doesn't do it. if I jump the relay 45 it does do 100% on the fan. So I first have to find the P0442 small leak that I think is causing the Shrt Trim and Long Trim to go up to 12 or 16 plus or minus. After that I have to see if the fan is doing the job from the PCM. Fan clutch is new.
 

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So, you know you have a bad relay.
You switched the relay with an other relay
The lights work
The fan doesn't
Seems simple to me
 

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Discussion Starter #10
Yeah I am ordering the relay from Amazon. The lights had a hick up that one time on the freeway when they went dark on me. So there is a problem with one relay for sure. Intermittent but there nonetheless. Will post if any progress.
 
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