E150 5.4L 83,000 MILES DTC 171, 174  1915 Ford F-150  Hi, I have
a 97 E-150 5.4, 83,000miles that codes 171, and 174. I have
crawled the whole engine looking for vacuum leaks, none found,
even the expensive elbow at the back of the intake. I checked
the fuel pressure, 30psi idle, 40 psi vacuum hose off, checked
the EGR valve ( valve works good.), Checked the egr vacuum
regulator (40 ohms) and cleaned all the inlet filters. The van
pings under light acceleration at freeway speeds, reguardless of
gas quality, and almost dies on initial cold startup. What am I
missing?  September 15, 2006.  If you can wait till tomorrow
when i go to my shop. i can look up thoes codes and tell you
what you are over looking or what to look for .but right off the
top of my head i don't remember what thoes codes are. why were
you looking for vaccum leaks was one of the codes no flow
detected? or encifucent flow decteted? this could be a help if
you already know.or O2 lean bank 1 .(NOS) 8)  Sep 15, 2006.