[Gmecm] $58 F29/F29E VE lookup weirdness

[Rob Handley]

I've been looking at VE for the last few days and, after putting test values 
in F29, F29E, and F30 I spotted the VE regularly (every ~6 secs) reverting 
to the F30 only value. Looking back at one of last year's logs this was 
happening then too. It also happens with the ignition on and the engine not 
running !

Has anybody seen this or have any suggestions why the table look up (as used 
for F29 and F29E) should be returning zero every now and then? I find the 
table look up code hard to follow.

Robin