idosubaru Posted July 16, 2008 Share Posted July 16, 2008 EA82 MPFI XT with no fuel in the engine bay prior to the fuel filter. in diagnostic mode i hear the relay clicking and can hear/feel the gentle hum of the fuel pump as it cycles on. i added gas and tried again just in case there was some crazy way i lost fuel. no dice. car has very little rust, whatever it has is surface from sitting for the past couple years i've had it. so i doubt the tank is rusty. going to pull the fuel pump lines tomorrow and check it out. anything else i'm missing? any chance the pump is whirring but not making noise? can they seize? Link to comment Share on other sites More sharing options...
bheinen74 Posted July 16, 2008 Share Posted July 16, 2008 check hoses they could be doubled over, bent enough to cut flow off. Link to comment Share on other sites More sharing options...
McDave Posted July 16, 2008 Share Posted July 16, 2008 Any luck? I would run a hose off the back of the pump to a gas can just to see if the pump is actually working. If it does then look for a pre-filter between the tank and pump, and/or kinked or cracked hoses. If all is well there then the sock filter in the tank is suspect. Link to comment Share on other sites More sharing options...
MilesFox Posted July 17, 2008 Share Posted July 17, 2008 Any luck? I would run a hose off the back of the pump to a gas can just to see if the pump is actually working. If it does then look for a pre-filter between the tank and pump, and/or kinked or cracked hoses. If all is well there then the sock filter in the tank is suspect. this does not apply since the pump is external. there is only one filter onthe firewall. the fuel return is after the injector, so make sure the lines are not backward Link to comment Share on other sites More sharing options...
McDave Posted July 17, 2008 Share Posted July 17, 2008 this does not apply since the pump is external. Yes, I figured the pump was external. Why can't you hook up a hose to the inlet and run it to a gas can to see if it will pump? Or did you mean to say the pump is internal? there is only one filter onthe firewall. the fuel return is after the injector, so make sure the lines are not backward He already said it's not even getting fuel to the engine bay filter. What does possible switched lines at the injector(s) have to do with that? Sounds like either the pump is bad or fuel is not getting to the pump. Surely these cars have some sort of filter before the pump, even if it's just a sock filter in the tank? Link to comment Share on other sites More sharing options...
Robert M Posted July 17, 2008 Share Posted July 17, 2008 Last time I had a fuel pump go out on my 87 wagon, it whirred and hummed just fine...but no fuel came through. They can run without actually moving gasoline sometimes. I think sometimes they will still 'run', but can't achieve the needed pressure. This is also why I bought TWO fuel pumps when I replaced it. The other is in my rear storage compartment, just in case it happens again offroad. No pump, you are going NOWHERE. My advice to the guy: Take a quick look at the fuel lines. If they look undisturbed and normal, get a new pump. Link to comment Share on other sites More sharing options...
idosubaru Posted July 17, 2008 Author Share Posted July 17, 2008 Why can't you hook up a hose to the inlet and run it to a gas can to see if it will pump? yes, the pump is external - and i've done that before. He already said it's not even getting fuel to the engine bay filter. What does possible switched lines at the injector(s) have to do with that? yes, no fuel to the engine at all (pre-filter) Surely these cars have some sort of filter before the pump, even if it's just a sock filter in the tank?you're basically correct - the fuel pump has a sock built into it! i haven't had a chance to mess with it yet but thanks for posting Robert M, looks like mine might be doing the same thing. car has little to no rust, low miles and hasn't seen much use recently so i'm not inclined to think the lines are in bad shape. i have extra pumps laying around so that shouldn't be a problem. Link to comment Share on other sites More sharing options...
McDave Posted July 17, 2008 Share Posted July 17, 2008 you're basically correct - the fuel pump has a sock built into it! Thanks for that tip GG. I never would have thought to look for a filter there. I'll be the first to admit I'm weak when it comes to Subaru layout and their idiosyncrasies, that's one reason why I'm here, to learn. But automotive diagnostics is my specialty. I'm usually not outright wrong. Link to comment Share on other sites More sharing options...
idosubaru Posted July 17, 2008 Author Share Posted July 17, 2008 i've yet to pull one that had even a dirty sock, i would expect contamination is rare. i never could figure out how to remove them either - the OD of the top seemed larger than the ID of the nipple in which they set in the pump. but i guess it doesn't really matter, not like they're hard to clean out. Link to comment Share on other sites More sharing options...
idosubaru Posted July 18, 2008 Author Share Posted July 18, 2008 Any luck? Pump was not pushing any gas, nothing. even though it was "humming" fairly normal - though it sounded "less" than it's replacement pump. not sure if that means anything though, but the new pump solved it. also checked the sock - it wasn't clogged. that would have sucked. Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now