Testing fuel pressure

[Rus]

Hello all!

I've been slowly fixing the issues on my 535i and have so far replaced the fuel filter, air filter, spark plugs, spark plug wires, distributor cap and rotor, all vacuum lines, and the rubber intake tube that attaches to the throttle body. This has resolved some of the issues, however the car still sporadically throws a code 1222 at idle and has a stumbling idle when cold. Starting also is somewhat difficult. I've tested the O2 sensor and get a constant fluctuation between .1 and .8 volts, which seems to be within the acceptable range. My next suspect is the fuel pressure. Where can I purchase a fuel pressure gauge to test the fuel system? Napa, Autozone, etc. do not stock gauges that can be used (domestic tester kits use a schrader valve attachment instead of just a T-connection). Also, how loud are the fuel pumps supposed to be in these cars? Mine is much louder than any I've heard before, so I wonder if that's grounds for suspicion. Thank you in advance!

[Bill R.]

fine , you can either remove the schraeder end from the gauge and using a T fitting some fuel line and some hose clamps. This will also allow you to bleed off the fuel pressure when your down since the autozone gauge has a fitting on it to relieve pressure. You can also get T fittings that have a schraeder on one side of the T so that you can use the gauge without modifying it. I picked some up at my local ace hardware for mine. I've heard both loud and quiet pumps and there's no predicting when they will fail, however typically the pump does get louder before it fails.





Hello all!

I've been slowly fixing the issues on my 535i and have so far replaced the fuel filter, air filter, spark plugs, spark plug wires, distributor cap and rotor, all vacuum lines, and the rubber intake tube that attaches to the throttle body. This has resolved some of the issues, however the car still sporadically throws a code 1222 at idle and has a stumbling idle when cold. Starting also is somewhat difficult. I've tested the O2 sensor and get a constant fluctuation between .1 and .8 volts, which seems to be within the acceptable range. My next suspect is the fuel pressure. Where can I purchase a fuel pressure gauge to test the fuel system? Napa, Autozone, etc. do not stock gauges that can be used (domestic tester kits use a schrader valve attachment instead of just a T-connection). Also, how loud are the fuel pumps supposed to be in these cars? Mine is much louder than any I've heard before, so I wonder if that's grounds for suspicion. Thank you in advance!