back at this thread, just in case some fresh eyes can help. my van runs perfectly. like new, besides the fuel economy issue. we did get it bumped up a couple of MPGs when we replaced the MAF and a tiny expensive cracked hose in the airflow system (not sure that's really what it's called). just to refresh, we've replaced:

1. catalytic converter
2. fuel injectors (though i wonder if these may still be a root of the problem due to shoddy workmanship, though no fuel smell)
3. MAF
4. O2 sensors (also wondering about these)
5. tires
6. total engine rebuild
7. 4WD rebuilt
8. high efficiency radiator
9. muffler

the van passes emissions tests with flying colors. no strange smells or sounds. could cheap fuel injectors be the problem without any smell or would they affect emissions tests?

thanks in advance,
kestrel