Okay I've had my 850 a little under a year now and I can't be sure how many miles it has, exactly because the odometer busted at 104K odd-miles. And lately (after oil change) my car will sputter when I turn the key but won't actually start unless I squash the gas pedal (starts about after 3). I've replaced the pcv and fuel filter six months ago and changed the fuel pump with a compatable one (not genuine Volvo or bosch, money was tight ) Now I live in the less attractive desert part of California so it's not very moist, but it has been very hot lately and the other day after filling my tank I took my car to the carwash and as I'm pulling it in, it just gives up and completely shuts off and it took me 5-6 cranks before it actually started and now ever since it will drive but with what feels like, less power. I'm wondering if the fuel pump maybe went out? Because it wasn't an actual Volvo one or I've read that maybe the purge/evap valve has gone bad? I have the Evap valve and money is no longer issue. So should I just replace the fuel pump or is it something else that I am unaware of I don't know much about cars, so any help and advice will be greatly appreciated. PS. I wanna make this last as my daily driver so I can have my future 850R or c30 as a project but I haven't decided witch one I want yet . Any opinions on witch you like better or would rather have?

 

Consider the fuel pump relay, fuel pressure regulator as well as the evap valve. You should probably start by measuring the fuel pressure at the valve on the fuel rail to see what it is at start up and at idle. Any other symptoms - ie check engine light?

 

P0442 evaporative emissions system leak (small leak). p0172 too rich bank 1. P0304 cylinder 4 misfire, p0305 cylinder 5 misfire, p0300 multiple/random cylinder misfire. I didn't have the misfire codes the other day when I checked the codes could it be the spark plugs maybe? As far as I know the spark plugs were never replaced

 

I'd say the 0172 is due to the spark. If you haven't done a "stage 0" tune up recently, I'd do the plugs, wires, rotor, cap all at once. Once in a while it may be the coil but the old school coils are very durable.

 

Okay so I replaced the distributor cap, rotor, plugs and wires and still no luck when I first put them in the car it fired up right away but the next day when I tried it was as if the problem never went away. It doesnt accelerate AS poorly but it isn't where it's supposed to be. It idles right below 1,000 rpms as opposed to idling right on 1,000. and when I turn on the AC it nearly shuts off. I also still have all the same misfire codes, besides the po172 code. could it be the coil maybe? I've heard people say it could be a bad 02 sensor? Also the other day when my rpms started to drop I revved up the engine to bring it back to normal and noticed gray smoke had come from my exhaust (witch has never happened before) so could that be my 02 sensor? I haven't replaced them since I've owned it and I'm not sure when they were replaced last.