Still no fuel pressure

drew525 · Post by **drew525** » 18 Jan 2007, 21:58

So I'm still having issues with my 95 850 turbo. I replaced my fuel pump with a pump that turned out to be defective. I received a replacement for the replacement and made sure this one worked before I installed it. So new pump is in and I can hear the pump running when I turn the key, yet the engine is still not getting fuel. I know the pump is working and I very recently changed the fuel filter yet there is still no pressure and the valve in the engine compartment. Is there something additional I need to do? I've tried turning the key on and off about 10 times before restarting it to build up pressure but still nothing.

Post by **pfeener** » 19 Jan 2007, 08:17

There's no "magic" here. It's just a pump. If you have no pressure, it's either the pump or a clog in the line. If it were me I would remove the fuel filter and the fuel pump and blow air through the line from the tank to the filter to be sure it's clear. Hitch it back up, put a hose on the fuel filter line and put the hose into a container and see if you can pump fuel. If the pump is running and nothings coming out, you have another bad pump. You didn't say what brand pump you have, but I would spend the extra and go with a genuine Volvo part. I've been burned so may times by after market parts.

Post by **MadeInJapan** » 19 Jan 2007, 08:38

Does gas come out of the shraeder valve at the end of the fuel rail?

bobsnow100 · Post by **bobsnow100** » 19 Jan 2007, 13:07

The pump should only run for a few seconds with the key in the ignition 1 position and once it gets full pressure in the system it stops, if it is continually running then you might of done something incorrect with your installation. Did you get a whole pump unit or just a replacement pump that you install in your existing pump housing. If you got a replacement pump, then did you tighten up the hose connectors to the pump with clamps and make sure they were hooked up correct. When you had the pump housing out did you see gas in there? Did you push on the fuel lines tightly and correct on top of the tank? Make sure no lines are pinched? There is a return line. When the pump is running does the gas come back through the return line? if so maybe the fuel pump regulator is bad. I would start back at the pump and keep working towards the engine.

CarVolvo · Post by **CarVolvo** » 19 Jan 2007, 14:58

All good advice above.

Just wanted to add you can see if there is pressure in your system either by the schrader valve MIJ pointed out but also if you have to start the diagnosis of where there is a plug you can do the following.

Remove the quick connect that goes to the fuel pump and remove it and place the end in a glass container. Make sure you dont do this in a enclosed space and make sure it is not near any flames.

Have someone turn the ignition on to position two and see if the pump is priming and shooting fuel. If it is then you know there is pressure.

If it is move to the other side of the fuel filter and do the same. Keep in mind that the fuel filter will always have some fuel in it.

If your getting sufficient pressure then the line must have a blockage or a kink in the line betwen the fuel filter and the rail.

If nothing is coming out of the schrader valve the it will confirm this.

I woudl not be surprised if your having this much problems with your pumps that you might have a large blockage which is flowing though the system. Its also possible that the gunk is also messing up the filter you installed.

drew525 · Post by **drew525** » 19 Jan 2007, 15:10

Thanks for the suggestions. The pump I put in is genuine volvo, it is good condition used out of a 96 850. There is no fuel at the valve on the rail, but if I push on the valve near the fuel filter there is fuel but only when the pump is running as soon as the pump stops there is just air in the lines.

CarVolvo · Post by **CarVolvo** » 19 Jan 2007, 19:53

so it could be airlock... just start doing the procedure i mentioned in the earlier post.

drew525 · Post by **drew525** » 21 Jan 2007, 09:17

Okay so I pulled the line off in front of the fuel filter and ran the pump. Gas did come through the line but it just trickled out, it didn't seem to me that there was a significant amount of pressure. This leads me to believe that this 2nd pump is also defective as it can't provide enough pressure. I'm going to order a brand new walbro pump kit and hopefully this fixes my issues.

CarVolvo · Post by **CarVolvo** » 21 Jan 2007, 10:54

OK so you took it off before the fuel filter and you got a dribble? THis is after someone tried to start the car as you observed right? ( and the gas tank is atleast half full?)

One last thing before you go after the rebuilt.

Would it be possible that the line is kinked up. Try to see if the pump shoots fuel from the pump itself.. run a vacuum line to it and clamp it down letting the tube go into a bottle to prevent spillage in the car.

Also it seems highly unlikely that all these pumps are not working. Did you test the two relays or did you already replace them and if you did..were they new parts?

drew525 · Post by **drew525** » 21 Jan 2007, 20:42

Yes I got some gas after i pulled the line but there was very little pressure and the gas tank is over half full. I also checked to see if the pump was shooting fuel by itself and it was but again with what seemed like very little pressure. I have ordered the rebuild kit and will keep you guys updated with progress. By the way I replaced the fuel pump relay with new OEM and tested the main relay which checked out fine.