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Ford Windstar Check Engine light-Codes P01171, P01-174

Check engine light came on shortly after we purchased a used 1999 Windstar several years ago. Ford Dealer refused to acknowledge pre-existing, ran diagnostics showing codes above (diagnostic cost $$) and suggested very pricey fix. My mechanic said only thing it affected was fuel consumption and could live with it. We have been doing so for the last 5 years.

Is this worth fixing? Car has approx. 85,000 miles on it and is paid for. Mostly local driving, occasional long distance, no more than 2- 3 hours highway at a pop.

Also, my mechanic says every Windstar he’s ever worked on has this problem, result of design defect. How does Ford get away with this without a recall???

Your codes have one too many digits in them.

Are they P0171 and P0174 (which I think is likely)

Or are they P1171 and P1174?

The two sets of codes are very different.

P)171 and PO 174 - how do they get away with a defect like this on every car they sell with no recall?

Slow down man. These codes are incredibly common on just about any car. Your mechanic’s impression of other Windstars is hardly a basis for concluding that there is some dark secret “defect” that Ford has covered up. Frankly, it is more likely that your mechanic doesn’t know what he is doing - or maybe he would have explained that these codes can have multiple sources (i.e. not “a” defect), and maybe he would have actually fixed the problem.

The codes are not a mystery - they just mean that the computer is detecting a “lean” condition (too much air in relation to fuel).

See this link for a clear story:

You can click the embedded link for P0174

  • Clean the MAF
  • Check for vacuum leaks
  • Check intake manifold for leaks (intake manifold gasket might have been the “pricey” option at the dealer)
  • Check the fuel pressure and give it a new fuel filter

How do they get away with it?

Well, it likely isn’t on every single car, plus a recall will generally happen ONLY for safety issues, not quality defects. Sometimes a manufacturer might do a goodwill repair for all owners to fix a quality problem outside of a recall (Ford did this for my 97 Taurus) or extend a warranty for a widespread quality problem (Honda did this for Accords and Odysseys suffering transmission failure after several class action lawsuits were filed).

But for your problem, P0171 and PO174 mean that bank 1 AND bank 2 are running too lean.

This does appear to be a common problem with the Windstar and its horrid 3.8L engine (thank God Ford got rid of that engine). Most likely the cause is a leak at the intake manifold gasket.

Here’s a page that seems to have fantastic detail on the repair process:

Cost appears to be under $100 for parts and the guy who did that page (experienced, but non-professional mechanic) said it took him 2.5 hours at a leisurely pace.

I’d peg a pro mechanic at under $500 to do this job, including parts, based on that time estimate + some buffer time + parts markup.

As for whether or not it is worth fixing, that may be debatable. The engine isn’t running properly, so it may end up with excess wear and tear… but the car isn’t worth much anyway. If your mpg is acceptable, I might be tempted to get a cheap code scanner to monitor the codes and make sure nothing else is popping up, and just live with it.

I did the above repair about a year ago. No more check engine light. Took more around 3 hours because I also replaced spark plugs while I had the intake cover off. I purchased the kit from Amazon, and also had to get some plastic washers from Ford. Took those washers to my local auto parts store and then returned the hugely overpriced ones to the Ford Dealer. Difference in cost $25 for a couple pieces of plastic. If you have the time, and are competent enough to change your own oil, this is an easy job.