The fact that you have your power back at night time is odd to me. I would of course first start with basic tune up items like spark plugs (PROPERLY GAPPED!! i prefer NGK BPR6ES plugs), fresh bougicord wires, fresh bosch cap and rotor. IPDUSA.com has the good stuff. Aftermarket wires can suck big *****.

What is the weather like during day/night where you live? Humidity and different temps can cause electronics to behave differently. If your wires, cap, rotor are old they can be sensitive to heat/humidity.

My 240 wouldnt even start in cold or rainy weather. It turned out plug wires were bad. Spraying water on them at night revealed sparks shorting out to ground from the wires.

I would also check your fuel pumps. Especially the one in the tank. It could be dead and cause low power issues. Open gas filler and stick a hose in your ear and down in the hole and listen for the tank pump with the car running.

If your fan is always running loud the clutch on it is probably shot. Either try another clutch, or convert to electric fan. I like the reliability of the mechanical fan, but I like the how much quieter, smoother, and faster revving the engine is with an efan. It might be beyond your means to get one installed right now anyways. Requires some reasearch and know how. One thing at a time.


Main pump is probably fine since your car runs. At least put a fresh BOSCH filter on there too. IPD also sells those. Fram and other aftermarket filters suck.

Oh hey, I still completely insist that you do your multimeter tests AT THE ECU.

PLOP!!!!!!!!! (electronically slams it on the table in front of you, again.....)

http://www.volvowiringdiagrams.com/v...20Complete.pdf

 

I will definitely do that multi meter test. I am curious to see how that goes I have never done it myself only seen others do it. I am not familiar with how the fan assembly actually works, there is a clutch in the fan? Apologies if that sounds stupid. Would make sense though, it only seems to work extra hard after I stop at a red light, or when I first start up the car. Possible that it is trying to get all of the hot air out of the engine bay thats not going anywhere while I'm sitting there? At night time when it is cool I never hear it winding up super loud, even if i stop for a long time. It doesn't sound like there is anything neccesarily wrong with the fan, just when its super hot its working really hard to get the hot air out of the engine bay.

 

Google it. Yours sounds fine but...

If noisy on cold start, that's not right, but ya its noisy when it gets hot enough to engage. Go spin with your hand cold and should spin " rather " freely.

 

Not the case. Fan clutch does engage on cold start for about a minute or two.

 

ok. Mine isnt noisy on cold starts.....

 

If your fan clutch does not clutch up on a cold start, then the fan clutch is beginning to go out. One can take a rolled up newspaper or similar and judiciously interfere with the fan blades to ascertain whether the clutch is operating or not.