E28 No start...heard this one before

[dg <davehg"nospam"@domain.elided>]

I know I saw this about three weeks ago on the digest; wouldn't ya know it 
happened to me.

As I started up the 86 535i 5spd, I heard a loud boom (like a backfire) 
coming from where the cat meets the exhaust manifold. Then, as I start it 
up, it now stutters and will not idle (simply dies). I recall that the 
poster had a similar problem and found that something had dislodged (like a 
hose or a sensor).

Now what? Any ideas? What was the thing that dislodged? All replies 
appreciated (especially from Rob and Larry F.)

- -Dave Green

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