Correct. Insofar as when the fan comes on. A: It's in stages. B: The stage (on or not) is dependent upon the system pressure in the A/C system and/or the radiator coolant outlet temperature. Both instances of coolant outlet temperature and A/C system pressure can be present at the same time. Whichever value is greater (demanding the most fan intervention) will be the dominant one until it's satisfied than the lower threshold takes over.
Example: You're returning to the car in a parking lot after 5 minutes. Engine was already warmed up. The car is hot and you want everything the A/C system has.
Starting the car and going full A/C could see two things happen:
The A/C system pressure raises significantly (High value) AND the hot coolant has just exited the block and the temp sensor @ the bottom of the radiator is activated. (usually a lower value than HOT car & full A/C.)
The DME needs to drop the pressure of the A/C system fast, the fan will ramp up to a higher stage. Then will lower and the "high demand" is satisfied for a bit. At the same time the DME sees that the coolant outlet is still a little high (it did benefit some from the fan running for the A/C system) and needs a little more. Now the lower threshold for the coolant outlet will usually see the fan run at a lower stage until that's satisfied and/or the A/C system pressure again asks for some more.
I had recently purchased headers that were made for the m54 engine under the impression that they would fit on the m56, then I noticed they didn't have the same bolt pattern. Since the two engines aren't the same size (m54 being a 3.0l and m56 being 2.5l) the headers won't work right?
hello. i am new to this site. it is my first post. i apologize if i could have found this answer somewhere on the site already. i dont really know how to navigate the site yet. anyway. is it a good idea to get a grease gun and needle, puncture the boot around the ball joints and fill them with...
Hey everyone, with spring on the way, I wanted to test my AC. Turned the dial to max three blue dots, the temp down and turned on the ac switch but it never kicked on. At first I thought refrigerant, but the ac compressor clutch isn't kicking in either and the secondary fan in front of the...
Good afternoon guys,
I was currently removing my intake mainfold when these two plastic fittings appeared. I don’t know what they’re used for, let alone where they belong. Can anyone bestow some knowledge upon me? Please and thank you
Hi fanatics, I need help dealing with this annoying/ embarrassing squeak that’s coming from my engine bay. I’ve tried replacing some old parts that could be related.. This is a list of parts ive changed to brand new OEMs:
Main idler pulley
Have also spun and lubricated the...
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