Vapor Lock with 912iS. Most probable location?

Daniel Shefter wrote:

I had what appears to be a similar issue last Friday.  I was flying my Flight Design LSA F2 with 912is engine back to Sedona with temperature in the mid-80s.  I was about 70 minutes into my flight and got low fuel pressure warning and lost a lot of engine power.  I had both fuel pumps on and no electrical issues.  I was on descending with about 3,000 RPMs. 

Situation corrected itself after 5-10 seconds (although it felt a lot longer!) so I was able to complete normal landing.  I haven't been able to replicate issue doing long run-ups on the ramp. 

I was using 100% Mogas (91 with 10% Ethanol and probably the winter blend) so I assume it's the same vapor lock issue that Paul experienced.  I'm switching to 50/50 Mogas/Avgas and maybe even 100% Avgas and just do more frequent oil changes. 

Daniel,

Were you climbing or cruising when you had the problem. What altitude?