Starving for Attention

[dc112675]

I think my Magna is possesed.  Started her up today, and she seemed slugish, and seemed to run rough (especially at low rpms).  Got out on a big road, and at 50 mph in 5th gear, she wouldn't go any faster.  I could pin the throttle and it just stayed right there.

So, based on what happened several weeks ago, I reached over and flipped the gas off.  After about 10 seconds she really came to life, and started taking off.  I flipped the petcock back on, and she is running great.  

I don't have the first clue why it is doing this, but apparently she does better after being starved of gas.  Could this have something to do with a vacuum?  That $600 at the mechanic is looking worse and worse . . .

Thanks for your help, dc

[MagnaMan]

You might want to check the vacuum operated fuel shut-off valve. It's on the right side right under your tank and is connected to the manual valve via a fuel line and has a vacuum line that runs to the front right cylinder. It has been known to cause these type of fuel starvation problems when the diaphragm starts going out.  There's a thread on here talking about it or at least the location of it.