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Should I get the latest PCM reprogramming?

06-09-2011, 11:55 AM
I have a 2000 Windstar with about 150k on it, did the Isolator Bolt fix and never had the PCM reprogrammed.

One of the things I wondered about was just what did they change in the programming relating to that fix? Could it be to make the 171/174 codes more difficult to trip?

I'm guess, but maybe I did the fix 20-30k miles ago, and now I have 171/174 back. Of course, this was right after my van sat for 4 months at the Ford dealership waiting for axle and subframe parts.

Regarding the fix, I did the inline oil separator, however, I did not do the valve cover fix.

Any thoughts?

06-09-2011, 01:07 PM
MrCreosote -

I did the isolator bolt fix on my '00 Windstar myself (so no PCM reprogram), and haven't had problems with them since. To the best of my knowledge, my van's PCM has never been updated (the only exception might be if the dealer did it during a recall without mentioning it to me).

I'd be suspicious that some other vacuum leak showed up to trip your 171/174 codes. Check every vacuum fitting - particularly on the back side - and make sure all is well.

Did you use updated OEM Ford isolator bolts or aftermarket isolator bolts? Just a thought - I have heard of aftermarket isolator bolts not holding up well.

I doubt the valve cover is your problem. Note that it's possible to modify an 'old' valve cover to match the 'new' valve cover's PCV baffle design, though your separator is probably accomplishing the same thing.

06-09-2011, 01:43 PM
I used Ford Isolator Bolts.

Also, I did the master cylinder pressure switch replacement to fix cruise control problem. So I had the air cleaner off and on a couple of times for troubleshooting and then replacement.

When I finished the replacement I realized I left off that 1/4" rube that pushes into the back side of the rubber bellows. I fixed that and drove around for a while thinking the 171/174 codes would clear but they didn't seem to.

So I cleared them and I'm waiting to see if they reappear.

Other than that, I didn't touch anything on the engine.

Of course, the Ford dealer might have.

You'll laugh at this. When they did the rear axle, they forgot to tighten the RHS trailing arm main pivot bolt. It subsequently fell out and gave me quite a shock the first time I ran over a dip in the road and the rear of my van suddenly went sideways about 12" and then snapped back.

The Ford garage wasn't even concerned about it. They said if I brought it in, they'd take a look at it. They had no problem with me attempting to drive it there even when I told them the bolt was gone. (!)

Boy, it sure was Squirrel City when you went around a LH turn and had to touch the brake. I think if you did that real hard, you could have had the rear end sitting beside the van.

I really don't have much faith in that dealership.

PS. I wonder if I could have a clogged injector? That would definitely cause an lean condition.

06-09-2011, 09:09 PM
That hose on the flex hose that you mention forgetting to connect is a likely cause of the lean code(s).
The air that enters at that point would be in the "vaccum leak" catagory because it is air that is entering the motor that the computer does not know about.
The MAF is part of that air cleaner "bullet".......and so any air that enters after that point is not measured and the computer does not know about.

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