240 Fueling/Electrical? Help please
#1
240 Fueling/Electrical? Help please
Hello I just recently purchased a 91 240 non turbo. It fires up and runs for a few seconds then dies out. Ive been reading that this model actually has 2 fuel pumps and am partial to starting there first however I am very green to antique volvos. Any tips/advice/direction is really appreciated.
#2
Yes there is a feeder pump in the gas tank, generates maybe 15 psi. On some cars there is a schrader valve under the car before the main pump to check feeder pump pressure. Main fuel pump is under the car, near the drivers seat. The fuel pump relay (it has a white plastic cover) is above the passengers feet under the dash and are known to get cracks in solder joints on it's circuit board and cause fuel pump power failure. If you turn the ignition on and bump the starter, you should be able to hear the relay click under the dash and the main fuel pump should buzz for a second. The relay turns power off if there is no spark present - but you can't hear the pump if the starter is spinning the engine over. You can always just pry the white plastic cover off the relay and close the relay contacts yourself to make the fuel pumps run. If there is not a schrader valve on the injector rail (can't remember when they started putting one there) you will need to t into the feed line, normal fuel pressure is about 45 psi from what i remember. Usually the cars will run with a bad feeder pump, but that made the main fuel pump fail early.
There are fuses for both pumps in the fuse box next to the drivers left leg.
There are fuses for both pumps in the fuse box next to the drivers left leg.
#3
Check out this site. Has a very nice description of diagnosing and replacing the in-tank pump.
In the Tank - 240 Volvo Tank Pump and Sender
In the Tank - 240 Volvo Tank Pump and Sender
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Often Befuddled (07-17-2020)
#4
I have a 93 240 wagon I'm working on. I've had trouble starting it at times. If you crank, it usually catches and starts immediately . But if it fails, then you better wait 5+ minutes.
Yesterday, while it was on the rack, we noticed one of fuel pumps was audible for a few seconds, pre-crank. But only once, then not again for several minutes. My guess was that was the fuel rail being pressurized, and it stopped when it was. But then why would I have to wait to succeed?
I read the linked article above, but it was about the submerged pump, not the inline one. Is my observation a dead end vs. a clue?
And if I need a pump, Rock Auto does not seem to differentiate between them in their listings.
Suggestions?
Yesterday, while it was on the rack, we noticed one of fuel pumps was audible for a few seconds, pre-crank. But only once, then not again for several minutes. My guess was that was the fuel rail being pressurized, and it stopped when it was. But then why would I have to wait to succeed?
I read the linked article above, but it was about the submerged pump, not the inline one. Is my observation a dead end vs. a clue?
And if I need a pump, Rock Auto does not seem to differentiate between them in their listings.
Suggestions?
#5
I suggest getting Volvo parts at a place like FCPeuro or IPDusa, which specializes in Volvos and similar imports, and have a reputation for only stocking good parts.
a defective in-tank fuel pump will cause stumbling and performance issues when you're below 1/3rd tank of fuel, but will seem to run OK with a full tank. however, the main pump will be noisy the whole time, because its having to work harder.
both pumps should come on for 1-2 seconds each time the ignition is switched on, regardless of fuel pressure. There's also a paperclip test on that website for testing both pumps individually via jumpering at the fuse panel with the tank pump fuse removed. one fuse terminal will power the in-tank pump (often only audible if you remove the gas tank and put your ear right near the filler pipe), and the other fuse terminal will power the main pump (usually easily heard from outside the car).
there's lots of other causes of hard starting like this, everything from weak spark to intake air leaks.
a defective in-tank fuel pump will cause stumbling and performance issues when you're below 1/3rd tank of fuel, but will seem to run OK with a full tank. however, the main pump will be noisy the whole time, because its having to work harder.
both pumps should come on for 1-2 seconds each time the ignition is switched on, regardless of fuel pressure. There's also a paperclip test on that website for testing both pumps individually via jumpering at the fuse panel with the tank pump fuse removed. one fuse terminal will power the in-tank pump (often only audible if you remove the gas tank and put your ear right near the filler pipe), and the other fuse terminal will power the main pump (usually easily heard from outside the car).
there's lots of other causes of hard starting like this, everything from weak spark to intake air leaks.
#6
Thanks, in my limited driving I've never had it stumble once running, full or not.
I'll jumper test the pump per the link. But I'm wondering about the mentioned relay & SOP.
If the pump should run for a few seconds every key-on, is it likely the white relay is the cause when it does not?
(On Hondas of the same era, the infamous Master Relay cracked solder joints is a "when not if" fail.)
I'll jumper test the pump per the link. But I'm wondering about the mentioned relay & SOP.
If the pump should run for a few seconds every key-on, is it likely the white relay is the cause when it does not?
(On Hondas of the same era, the infamous Master Relay cracked solder joints is a "when not if" fail.)
#7
Thanks, in my limited driving I've never had it stumble once running, full or not.
I'll jumper test the pump per the link. But I'm wondering about the mentioned relay & SOP.
If the pump should run for a few seconds every key-on, is it likely the white relay is the cause when it does not?
(On Hondas of the same era, the infamous Master Relay cracked solder joints is a "when not if" fail.)
I'll jumper test the pump per the link. But I'm wondering about the mentioned relay & SOP.
If the pump should run for a few seconds every key-on, is it likely the white relay is the cause when it does not?
(On Hondas of the same era, the infamous Master Relay cracked solder joints is a "when not if" fail.)
#8
It usually takes a magnifying glass to find the cracked solder joints on the circuit board - seen as a little fuzzy ring around the joints carrying the most current.
It's easy to take the cover off the white relay and observe it working, or manually close the contacts to test the pumps.
#9
Hmm, thanks. The pump we heard was running for 2-3 seconds pre-crank. I'd assumed that was precharging the fuel rail; I think that's how my CRX and E30 work[ed]- a short run prior to starting. I guess Volvo is waiting for actual cranking.
Is this white relay a plug-in one? I'd first try to clean and re-solder the connections; that's the fix for the Honda plague.
I'm not going to do ANYTHING for a week plus; we're having a horrible heat wave here.
ps: The E30 pump makes 100-150 psi. A previous owner snarked it was designed by a Messerschmitt pilot who never wanted to lose power during hi-G maneuvers...
Is this white relay a plug-in one? I'd first try to clean and re-solder the connections; that's the fix for the Honda plague.
I'm not going to do ANYTHING for a week plus; we're having a horrible heat wave here.
ps: The E30 pump makes 100-150 psi. A previous owner snarked it was designed by a Messerschmitt pilot who never wanted to lose power during hi-G maneuvers...
#11
Relay is located above the passengers feet, dangling from 6 wires under the dash, (was originally clipped onto something) sometimes gets positioned facing down, water leaks from windshield and fills it with water!
#16
References
Hello I just recently purchased a 91 240 non turbo. It fires up and runs for a few seconds then dies out. Ive been reading that this model actually has 2 fuel pumps and am partial to starting there first however I am very green to antique volvos. Any tips/advice/direction is really appreciated.
https://www.240turbo.com/volvorelays.html#fprfailure
#17
It usually takes a magnifying glass to find the cracked solder joints on the circuit board - seen as a little fuzzy ring around the joints carrying the most current.
#18
If so, can I tell which it is by a VIN lookup?
#19