Did you ever figure it out??
I was having hesitation and miss fires for the last 3 weeks, and couldn't figure out why. On a hunch, and after reading many posts on svtp, I thought I would try changing out my plug wires, as I had installed new FRPP 9mm wires about 6 months ago.
So I bought new Motorcraft 8mm wires to switch out FRPP, and yup, hesitation and misfires are now gone. Great!
But now I am throwing P0171 and P0174.
I've read all about the vac leaks, exhaust leaks, possible failed MAF, etc.
I've checked all my vac lines (without smoke machine), and they all seem to be properly seated without hissing or observed leaks.
looked under the car at the exhaust, where my OR/X meets up with exhaust manifolds, and flange/bolts are tight. Same for where midpipe connects to X, although that is post 02's so it shouldn't make a difference.
The only thing I haven't done is change the 02's, which I've ordered and are on their way. Like you said, what are the chances both fail at same time, but car is 20 years old, and presumably never changed (80k miles).
I'm switching them out next week, and hope that solves my problem.
In the event it does not, did you ever determine a correct fix?
Thanks for your help.
https://www.svtperformance.com/forums/threads/damn-p0171-and-p0174-cant-figure-it-out-help.928002/
I was having hesitation and miss fires for the last 3 weeks, and couldn't figure out why. On a hunch, and after reading many posts on svtp, I thought I would try changing out my plug wires, as I had installed new FRPP 9mm wires about 6 months ago.
So I bought new Motorcraft 8mm wires to switch out FRPP, and yup, hesitation and misfires are now gone. Great!
But now I am throwing P0171 and P0174.
I've read all about the vac leaks, exhaust leaks, possible failed MAF, etc.
I've checked all my vac lines (without smoke machine), and they all seem to be properly seated without hissing or observed leaks.
looked under the car at the exhaust, where my OR/X meets up with exhaust manifolds, and flange/bolts are tight. Same for where midpipe connects to X, although that is post 02's so it shouldn't make a difference.
The only thing I haven't done is change the 02's, which I've ordered and are on their way. Like you said, what are the chances both fail at same time, but car is 20 years old, and presumably never changed (80k miles).
I'm switching them out next week, and hope that solves my problem.
In the event it does not, did you ever determine a correct fix?
Thanks for your help.
https://www.svtperformance.com/forums/threads/damn-p0171-and-p0174-cant-figure-it-out-help.928002/
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