hey all. I've got a '01 Mazda Tribute ES-V6 and I've been having some problems with it for the past 6 months or so. It is idling rough when I start it cold. After it warms up it idles fine. We have brought it in to Firestone when the service engine light came on the most recent time and the diagnostics test came up with 2 error codes: #171 & #174..... Below is a list of everything that we have done with it to try to fix the problem, but it still idles very rough from a cold start. I'm not sure where to go next on it. If anyone knows anything (reliable) about this problem or has a suggestion, please write back! thanks...

mass air control sensor replaced
idle control sensor replaced
pcv valve replaced
all 6 coils replaced
recent tune-up (all new spark plugs)
fuel, oil, air filters are good.
new transmission (6 months.)

 

I would check for vacuum leaks first, if you don't find any problems their I would check fuel pressure, I can'tgive you aspec of the top of my head because I don't work on a lot of fords.

The two I mentioned are the most likly to cause a lean code on both banks, but you may just want to find a reputable shop and pay them to look at it.

 

Definitely check carefully for vacuum leaks. Both codes are indicating adaptive fuel control lean limit has been reached. PCV hoses have been known to blow off and have seen several plastic intake manifolds that have warpedenough that the intake gaskets could no longer seal.