I started a new thread because the original was very far back. To fill you in, though, I followed directions from a site I was referred to to fix the service engine light which comes on with codes 171 and
174. I cleaned and then replaced the maf sensor, the IAT sensor, one oxygen sensor, the engine control coolant sensor and the dpfe. The car has also been tuned with new plugs, pcv valve and air cleaner. I remain suspicious of a manifold vacuum leak, partly because one manifold bolt wasn't tightened well after replacing the alternator and also because there are few possibilities left. The fuel trims you refer to are the adjustments made by the PCM, is that right?
Your vacuum gauge isn't going to give you the info you you are really
> after... A good scan tool that can display live data is going to be your
> best bet.... Long and short term fuel trims - both read when the freeze
> frame data associated with your lean indicator codes show when the code(s= )
> set is duplicated.... watching O2 sensor activity can also help to some > extent...
>
> Assuming that anyone has read any of your previous posts isn't a good
> thing.... Try to keep everything in one thread where possible... If that
> isn't an option (for whatever reason) restating everything becomes
> necessary... Anything else is starting a story in the middle.... >
>
>
>
> > Still have problems with lean mixture indicators on my Taurus with 3.0
> > vulcan engine. =A0I want to check manifild vacuum. =A0I have a gauge bu= t
> > don't know where to tap into the vacuum. =A0Advice?- Hide quoted text - >
> - Show quoted text -