Check the sweeper arm in the AFM.
I bet you have a worn spot...
OR your fuel pump relay could be going south.
Your bus is still Fuel Injected if I remember correctly.
Good luck.
KC

Check the sweeper arm in the AFM.
I bet you have a worn spot...
OR your fuel pump relay could be going south.
Your bus is still Fuel Injected if I remember correctly.
Good luck.
KC

Thanks guys.  I just looked it up in the service manual and it says this is not a serviceable part.  I'm about to go take a look and see if the pot is worn.  If so, this is the replacement, right?

https://www.busdepot.com/410020

And your right about fuel injection.  I should have mentioned that.

Is this a legit quick fix?
http://www.amazon.com/DeoxIT%C2%AE-FaderLube-Liquid-squeeze-solution/dp/B003D8G83O/ref=sr_1_2?ie=UTF8&qid=1349362631&sr=8-2&keywords=fader+lube

Is the replacement AFM a drop in replacement?

I think the obvious wear is the problem but are there any other ways to fix this without replacement?  I just don't want to replace it if I don't have to.

This is what I did:
See those 4 screws (phillips) that hold down the silicon board,
Loosen them and GENTLY shift the silicon wafer about 1/32" to one side or the other, the hard copper lines will give ever so slightly front/back, left / right I don't remember.
USe a wooden wedge or pencil or something to hold it off centered on the screws while you tighten back down the screws.
This worked on the 76 that I had because it moved the contactors to a different pathway on the carbon tracks.
Try it, it costs nothing.
KC

Sounds like they sent the wrong AFM or it is faulty.
The flap was stuck in the '78. I had to open it up and the tracks on mine were new looking, no wear.
Good luck
KC

We use to see a lot of Bent doors (flap) in the AFM do to a severe back-fire.  Made out of pot metal and not easy to bend back , but have done it.

Here is what is unbelievable...

I have spent a lot of money at Bus Depot.  No joke.  They are my go-to.  Well, their invoice lists the part that I ordered but the part itself and the box list a different #.  The AFMs are actually slightly different just looking at them.  BD swears that they are interchangeable.  Regardless, the new one won't turn over but the old one will.  So I have spent quite a bit of time on the phone with them and quite a bit of time checking and re-checking the install because they swear it is my fault.  I've cleaned all grounds and verified vacuum.  Still, the new one won't work.  So after all this BD gives me the contact info for the re-manufacturer.  I call them and they say it's defective and to send it back to BD.  Bus Depot says did they give you their address to return it to?  At this point I'm pissed because they service manual lists different part #s and says "It is important that replacement intake air sensors have the correct part number" right before it lists the numbers that Bus Depot says are irrelevant.  I bought the right part # which is stated on my invoice but they sent me a different # and on top of that it doesn't work.  Now they want me to ship the new one and my OG AFM to the re-manufacturer and have it rebuilt.  They have offered to reimburse me for shipping.  When I talked to the guy at the re-builder's he did suggest that as an option but knew it was bogus because of how long the whole process would take.  That's why he said to just send it back to BD.  I've got one more shot with Bus Depot on the phone when they open today at 11 for them to man up and take responsibility or else I'm out.  The tenor of the previous conversations suggests that they are going to stick to their guns and I'm stuck $230 in without a working AFM and a downed bus that I had plans to use in a week.

Am I missing something?  I run my own business and know that I would never do this to a customer in a million years.  Especially one that has spent as much $$$ as I have!  Am I somehow blinded by something?  I want to be fair, so let me know...

I think you guys are right about the fuel pump safety switch, but other than adjusting the CO mixture, there is no way to adjust the new AFM without opening it up -which I won't do because I know it will definitely screw my chance of returning it...