Just an idea about the wide-open situation ... this is based on my 616.912 so it may not apply. There should be a spring on the back of the IP from the side of the pump to the throttle linkage lever. IIRC it's about 1/2 inch diameter and maybe 1.5 inch long. Mine came off while I was doing a valve adjustment and afterward when I started it up it went to wide-open, scared the pants off me. I tampered with the throttle linkage and got it to start normally, but no matter what I did, it kept jumping up to WOT when I touched the pedal. I gave up and took it to my mechanic. He noticed the spring was missing, replaced it, didn't charge me. So ... if the 617 is supposed to have that spring, check for it. If you can get that solved, then check into your vacuum situation. My car wouldn't shut off at the key when it first ran off wide-open like that, but once I got the spring on there and got the idle speed normal, it shuts off very easily at the key. Knock on wood ... the way my cars have been lately, I shouldn't take anything for granted ...

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