Not sure

[rogerch]

I took it out for a quick run yesterday temperatures were in 80s Fahrenheit, and I was going up waterfall way an Alpine style road up to 2,500ft above sea level. I had no problems on the way up and yes I gave it heaps well into 3 figures and more on the speedo, boosting well, doing everything it should.

I didn't notice any problems on the way down, until I got down to the freeway, the last 10-15 ks home, I noticed it had got hotter than going up, still not enough to bring the fans on, but hotter. Also holding a constant 3,000 rpm on the flat the engine felt faintly fluffy, not enough to show on a gauge, in fact only just noticeable to the atentive like me.

When I got home I turned it off then back on again, and could hear the fuel pump what sounded like unable to produce pressure, after cooling down that went away, so I'm leaning toward fuel vapurisation, the other alternative is (I think) wastegate seeping presure, doesn't show any fluctuation on the gauge, but whatever it is, it's marginal.

Anyone got any thoughts or suggestions.

Roger

[rogerch]

Well let me put it this way.........anyone know the symptoms of a fluttering waste gate?

[trackmagic]

Roger,

Higher altitude might explain the slightly higher engine temp (thinner air). In terms of vapor lock I have seen here in the states the new blended fuels (ethanol) vapor locking at relatively low outside air temperatures, especially the low octane fuels. I fuel only at the branded fuel stations (Shell, Chevron, etc) to help insure the best quality fuel. I also will use AVGAS (when affordable) as it burns really clean and the fuel standards are better.

Good luck,

Jeff

Edited January 31, 2009 by trackmagic