A happy New Year to all.
The main fuel pump on my 86 740T has been noisy for a while. Performance has been good, although it is running lean and I have been unable to richen it.
I inserted a hose with a funnel into the fuel filler, and I THINK I hear the intank pump running, although there is also the sound of air being drawn into the system, like finishing the bottom of your milkshake with a straw.
I pulled fuse 11 (in-tank pump), and after a moment or two of the car idling, the car stumbled a bit then seemed to correct itself.
I removed the return line from the back of the FPR and replaced it with a clear hose, draining into a bucket. There was lots of fuel coming out, perhaps a half a gallon per minute or better, but it was very mixed with air bubbles.
Is this a sign that I need to pull the intank pump and make some repairs?
Is the fuel coming from the FPR supposed to be a steady (un-bubbly)stream?
Would this be a cause of the car running a bit lean?

Thanks
JD

I should have added that the fuel level is at half a tank. However, the noise level of the main pump, to the best of my recollection, is high regardless of fuel level.
I have been reading my Bentleys for my 240, and I see that the in-tank pump may simply be on its way out, and that it does not always fail at one stroke. Still looking for help!
JD
65 1800S
84 240GLE
86 740T auto
88 740T 5 speed
92 960GLE
97 960GLE (daughter's wheels)