 Engine Code "Mixture Too Lean"
Hi All
I’m new to this forum, but as I have a 98 Windstar, 3.8L V6 AT with many ‘issues’, I’ll probably be here a bit. I’m an amatuer home mechanic/do-it-yourselfer, and prefer to work on my own vehicles before paying $$$.
Today’s issue is: “Too Lean” Engine Code
The engine light is on, and the guy at AutoZone read the problem code to be ‘Mixture Too Lean’ or something like that (#171 or #174 – can’t remember). This is apparently the only code showing. The only indication of a problem other than the indicator light itself is a slight intermittent stumbling when cruising at relatively low highway speed/low rpms (~50-60 mph & ~1500 rpm). However, the van did this before the engine light came on. The problem is that with this engine indicator code showing, the vehicle will not pass the Maryland state emissions inspection required every 2 years and now due on my van. (Although the emissions could be absolutely A-OK – the state refuses to actually TEST the emissions on 96 or later vehicles!!!). The engine is completely ‘stock’, except that I have installed Autolite Double Platinum plugs in all 6 cylinders.
Questions: What sensor gives the “Too Lean” reading? (i.e. O2, CO2???) What could be causing a “Too Lean” condition, or just the “Too Lean” signal??? What are some possible fixes? Thanks for any assistance.
Best Regards,
CraigRK | 
