last weekend while it was raining i drove my car and it sputtered and stalled at a light. i pulled over and it ran poorly for a minute and seemed to straighten itself out.
this weekend after sitting for a day it wouldn't start. it would crank hard, but just wouldn't turn over. eventually after several attempts i got it to start, but it eventually stalled when i turned the interior fan speed up. my father thinks it's a fuel issue.
also worth noting, the coolant has been low recently. due to rain, i haven't been able to tell if it's leaking or where.

any advice is much appreciated!

 

Believe your father. Check a few threads about stalling and read up on fuel pump relays. Jump the relay and see if it starts.

 

i've read some threads and i'm still not clear on how to determine if it's the pump or the relay. i also don't understand what "jump the relay" means or checking fuel pressure "from the rail."
there are a lot of threads on the topic, they just don't explain what i want to know.

 

Pull the fuel pump relay and install a wire or paper clip from pin 18 to pin 57.
https://volvoforums.com/forum/volvo-...p-relay-56681/

Once you get the wire installed try to start the car. If it starts and runs, you likely have a bad relay. If you do not hear the pump running, then you likely have a bad fuel pump.

If you hear the pump and it still doesn't start, maybe you have another problem like a bad maf or some other issue.

 

cool, thanks!

 

the fuel pump is making noise when i turn the key. does that automatically mean it's neither the pump nor the relay?

 

When you turn the key you hear the fuel pump ... in a perfect world that would mean the wiring, fuse, relay and pump are all good. It's still good to know but in the real world you can still have a problem with the pump making noise as it's getting electricity but it may be very worn and not able to consistently pump enough quantity of fuel or at a high enough pressure. Then it could be that the pump is great and has years left but because of a bad connection anyplace in the circuit it's not getting enough voltage or amperage to pump the fuel it can. That would include burned contacts inside the relay. You turn the key and the circuit to pull in the pump contacts pulls them in but the contacts are pitted and or burnt and a bunch of the power that should go to the fuel pumps motor gets lost at those contacts. Or, a bad connection someplace along the harness. You need to find the valve on the fuel rail and beg borrow or buy a fuel pressure gauge to see if you're getting the correct pressure. On an 850 I think it's about 42-46? If you have the pressure then you usually have the volume but to test that you need to disconnect the fuel line where it comes over your timing belt and run a hose to a container so you can measure how much in a certain period of time. The other thing to check would be to test for voltage at the fuel pump lead in at the tank. You can go through the access hole in the floor to get to the wiring. Sooooo much easier than dropping the tank, thank you Volvo! You should get about battery voltage from that lead to a good ground. If you drop below 11 volts you have something wrong eating current upstream on the way back to the battery positive. You can either take it in and have someone trouble shoot it or take a gamble if the reading is low and try a relay.

 

If you are getting good fuel pressure like Kiss explains, you should be getting volume. In that case, when was the last time the fuel filter was replaced.

When you say you can hear the fuel pump when you turn the key, at what position do you hear the pump? Usually, when you put the key in, turn it to II you will hear the ICV under the hood. If the car is NOT running, you should only hear the fuel pump when you are trying to start it (position III) and about 3 seconds after you release the key. The motor is usually making to much noise (starter, valves, etc.) while you are trying to start it to hear it but you can usually hear it hum for the few seconds after you release the key.

 

CJAAMA --> If you hit the key and the starter motor turns the engine, then your motor is turning over it just isn't starting. I'm not sure I want to assume that. Your engine is turning over, cranking but not starting and you have checked for spark?

To edit my test for battery voltage at the pump, that needs to be done when the pump is running. Some circuits control by switching the ground which would give you battery voltage at the terminal any time the key is on but it's more likely the relay switches the positive so you'll only have voltage present for those couple seconds when you're cranking the engine over or when it's running.

Per RSPI --> I always take it for granted anyone with a fuel problem would first pull the filter and either check it (blow through it) or just install a new one and go from there. The basics can always bite you in the butt.

 

does autozone lend out fuel pressure gauges?
the check engine light has been on for over a year (while it has ran fine). if i have it checked, will it tell me if it's the MAF?

 

I don't think anyone loans them out. I think it's because they come back smelling of gas and it might be a fire hazard.

BUT, most places will loan you the code reader but to take it home you'll have to buy it and then get the refund when you bring it back. It would be nice if you had read the codes earlier so you could have erased them and then seen if they reset.

Have you checked for spark?

Have you tried to spray a bit of starting fluid in it to see if it'll fire?

 

i ended up borrowing a fuel pressure gauge, but i'm not sure where you test the pressure from (or what the "rail" means) or what kind of valve fitting i'll need.
tomorrow is the first chance i'm going to have to finally try to work on it. the first thing i'm going to do is change the fuel filter. any tips?

 

in the process of attempting to change the fuel filter, i manage to break a piece of the fuel like. the piece that came out of the front of the fuel filter into this thing:



there was a plastic nipple that came out of the thing in the picture above, which snapped. i have a feeling i now have to replace the entire fuel line from the engine back to the filter.

anyone?

 

Is it a plastic line or metal? If it's plastic dorman makes a repair kit that you can get at a parts store and the same thing if it's metal. You just use brake line and for the fuel system you can safely use compression fittings so you don't have to double flare it the way you have to for brakes.