1995 Volvo 850 Two Wheel Drive Automatic 160000 miles
I have the car above its a 850 glt non turbo with 5 cylinders. The problem I have is the car lacks power between the 1500 and 3500 rpms, for example when I start driving after leaving the parking place, if I try to climb a hill with a speed less then 60 miles the speeds drops until 25 miles, but if I climb the same hill with a speed which is higher tans 60 no prblems. Also there is a rattling sound coming near the exhaust manifold under steering wheel, if I press the accelerator a little more rattling increases if I move my feet a little from the pedal rattling decreases but there is always a slight rattling. This car is a well maintaned car I'm the third owner, and I personally know the previous 2 owners also there are 2 things which were never changed in this 12 yrs old car. Those are the fuel pump, and the catalytic converter, rear muffler is also never replaced, 02 sensor is not replaced, I doubt that the car's converter is plugged do you think a 12 yr old cars converter is plugged, cause some people say these converters last the life of the vehicle and should never fail. Also I need to tell yo, all the engine mechanical and electrical checks are made, there is no compression loss, valves, igniton system are ok. Transmission is also tested and is ok. One last thing the rear exhaust pipe has black deposits and they are very intense. Does this mean this car is running rich on fuel? And the converter might be damaged? And also does this mean the o2 sensor is bad too?
I have been asking too much and writing too long but I hope you can help.