Hi folks. first time here.

I've just bought a 10 year old 850 T5 upgrading from a 20 year old 740 (still weeping) there appears to be a strange humming noise coming from the rear of the car. It's not a mechanical sound like the axle or that, its there when the car is stationary. I thought it might be the fuel pump or air conditioning or something. Any ideas? it sounds like it should be there but all there is, is the petrol tank and boot! sorry, the trunk, (im in the scotland, thats what we call the bit you put your luggage in)

 

Does it do it sitting still or only while driving?

 

Both. Its very weird. It sounds like I'm sitting in airwolf or something

 

...does it sound electronic?

NM...i've no clue on this one

 

It's sounds mechanical but not in a klunky way. Imagine a quiet engine humm but from the back. Its so weird. I feel like a fool.

 

Maybe a Bad fuel Pump or the Exhaust is sitting on something.

 

am going to get it serviced. Am reluctant seeing as the the garage owner persistently keeps trying to tell me to get a citroen saxo or even a vw golf diesel or a passat diesel. He told me I was crazy for keeping my old volvo on the road i want to see his face when i roll up in the T5. CHUCKLES ALL ROUND. I have never driven a car with as much poke as this 850. I miss the whoooosh a 740 has.

 

So, next question, the lambda sond o2 sensor light has come on, on my new 850, am spending more on this than the 740, I'm going to get a new sensor tomorow for £180. How long can I expect the car to operate for before it starts stallin it's *** off? (unchuffed and hankerin for my 740 back) the 850 has a computer. woopy :-(

 

It just might run crappy till you get it replaced.

 

thanks

 

If you have ever been around an OBDI GM, that sound is from the fuel pump. To check if it's the fuel pump just have some one switch the car from acc to on (don't start it) while you listen next to the gas tank, if you here it prime (wine up) but continue to do it, might be the pump. Then turn it on and see if it is still there. On GM's, it is normal. I can here it from a mile away.