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2k1 STS
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Discussion Starter #1
My check engine light came on the other day in my '01 STS. She seems to be sputtering a little bit at idle, but nothing too bad. I ran the OBDII codes and came up with 2 current and a handful in history. I searched here and google for the 2 current codes, but can't find anything on them at all.

PCM d0171
PCM d0174

Anybody know what is up with these two? Is my car doomed?
 

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Discussion Starter #3
That's probably it, although I could of sworn it was a D. Now I'm off to figure out what that means. Thanks for your clarification.
 

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98 Deville, '15 Ford Fusion Hybrid Titanium, '12 Ford Escape
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That's probably it, although I could of sworn it was a D. Now I'm off to figure out what that means. Thanks for your clarification.
No problem...I'd give more info but I don't have my FSM with me.
 

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Discussion Starter #5
Looks like a tear in the plenum could be causing this. This doesn't look like too difficult of a procedure to do myself. Does anyone know how easy or difficult this is?
 

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98 Deville, '15 Ford Fusion Hybrid Titanium, '12 Ford Escape
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Discussion Starter #7
Should I try the spark plugs and wires before I try the plenum thing? That seems easier than removing the intake and replacing the plenum.
 

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Should I try the spark plugs and wires before I try the plenum thing? That seems easier than removing the intake and replacing the plenum.
I thought the plenum was in the spark plug wires? Someone else may need to chime in now. :eek:
 

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'98 STS (RIP @ 206,xxx miles)
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My check engine light came on the other day in my '01 STS. She seems to be sputtering a little bit at idle, but nothing too bad. I ran the OBDII codes and came up with 2 current and a handful in history. I searched here and google for the 2 current codes, but can't find anything on them at all.

PCM d0171
PCM d0174

Anybody know what is up with these two? Is my car doomed?
Given that these are P codes, this is an unmetered air situation - not an ignition or fuel supply problem.

There is a rubber sleeve type piece that has a history of cracking and allowing air to be pulled into the intake; air that is not measured by the MAF sensor. Hence the lean condition.
 

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White Diamond '03 DHS (with DTS floor shift)
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You have a vacuum leak common to both banks. The plenum is a common leak point in the 2000+ engines. The "plenum" is the rubber coupler between the TB and the manifold as opposed to the intake manifold on most other engines. Check the Tech Tips section. I just copied a "How To" into that section.
 
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