Sorry to start a new thread on this subject, but I think I'm finally tracking this thing down. FIrst of all about 4 months ago, I had a starting problem that turned out to be a fuel pump relay. They didn't have a black one like the one that was in it, but they said they white one would work. I'm giving this info just in case it has any bearing on my problem. Now, My battery will drain overnight for no good reason. I noticed a hissing sound under the hood on the left side of the engine that would stop when I disconnect the negative battery cable. This morning I also noticed a humming behind the drivers side rear wheel..... in tank fuel pump I suppose. It seems to be running when the engine is off. It doesn't do it all the time. I suppose also that that could simply be the fuel system repressurizing from where I had the battery cable off overnight. I did pull teh negative cable off teh batery and put a test meter on it to see if there was any draw, but there didn't seem to be (although there was no hissing or "pump humming" at the time. I suppose if it's doing it again, I could disconnect teh fuel pump relay and see if it stops to try to isolate it.

Any ideas would be GREATLY appreciated! Sorry for being so long winded.

Stevo

 

Your car should have the white 6 terminal relay on the passenger side.

Did you figure out what part is humming under the hood? Can you take a picture and post it of the part that was humming?
That might make it alot easier to find the problem.

 

Alright, I checked all the fuses with a test light and couldn't find a parasytic draw. I also couldn't isolate the hissing sound under the hood. I finally admitted defeat and took it into my trusty mechanic, boxy swedish auto. These guys are world class volvo mechanics and quickly figured out my problem. ADVANCE AUTO SCREWED ME!!!! A few months ago, I was having an intermitent problem with my 240 not starting. Turned out to be a fuel pump relay. Well I went to Advance and the pulled the specs on my car and had the relay in stock. Only it wasn't the same color. It was white, or black I can't remember, anyway it wasn't the same color relay but they said it was the one I needed. Guess what..... NOT!!!! The WRONG relay was making my fuel pump run while the car was turned off and was draining the battery. Nice to have a working car again! Thanks to tech for all the help!!!!!!

 

Glad it is all fixed now!!