P0171 & P0174 Mystery

[kingranch350]

Happy Thanksgiving to all,

I'm trying to tackle this job of locating and replacing the pcv vent hose elbow that seems to fail on our Taurus's and which is giving me both po174 & po171 error codes along with poor mpg's.

I've been googling all morning long to try and find a picture or video as to where the YF1Z-6A664-AB is located on my car? Most of the searches yielded results of DOHC.

Please point me in the right direction.....I have enclosed some pictures of my engine.

KR

[ellmarsh420]

in the 2nd picture, the pcv valve and hose is on the rear valve cover, near the firewall. It is under the wires in your pic, there is a grommet under it and the elbow is attached to the valve and has a hose going to the other side of intake. Hope this helps.

[kingranch350]

Originally Posted by ellmarsh420

in the 2nd picture, the pcv valve and hose is on the rear valve cover, near the firewall. It is under the wires in your pic, there is a grommet under it and the elbow is attached to the valve and has a hose going to the other side of intake. Hope this helps.

ellmarsh420,

Thanks for pointing me in that direction. My follow up question is, i tried tracing this hose to where it ends? i didn't notice the elbow on the other side that matches this part YF1Z-6A664-AB?


Please excuse my brevity on this subject. From reading the other forums on how to fix the po174 & po171 error codes it appears to be a simple fix that i should be able to handle? I just need help locating where YF1Z-6A664-AB is in my car?

KR

[ellmarsh420]

well that one is from the duratec , vulcan is different and doesnt have the one pictured. The problem with the vulcan is the rubber elbow that attaches the valve to the hose in the back. how does the elbow look on yours ? is it broken?

[Breeves002]

Yes, the one you have pictured is for the DOHC. I think that you bought the wrong part, and kept searching for it, that's why you kept finding the DOHC pictures.

It isn't a hard fix, just replace that elbow.

He circled it in the picture above in black (of all colors ). Usually those codes are caused by a busted PCV elbow.

I put it in blue. It is on the REAR cam cover passengers side where I indicated by the "PCV" I wrote in blue in the picture. I marked the FRONT cam cover. The back one is identical, just on the back. The V is at a 60 degree angle. One side of the V has the front cam cover on top, the other side is the rear cam cover. It's below and behind the EVR more towards the middle of the motor than the EVR, but not by much. It should have an elbow and tube going from it to the other side of the motor to the back/lower side of the intake manifold. The EVR is mounted on the intake manifold, and the EGR is on the rear of the intake manifold.

[danhasenauer]

Except on a Vulcan, those "cam covers" are called valve covers. The Vulcan is a single-cam, push-rod engine.

[kingranch350]

Originally Posted by ellmarsh420

well that one is from the duratec , vulcan is different and doesnt have the one pictured. The problem with the vulcan is the rubber elbow that attaches the valve to the hose in the back. how does the elbow look on yours ? is it broken?

Yikes! i just showed my ignorance....that would explain why i was having such a hard time finding the this part on my vehicle and on Google/youtube?

I'm on my way to my in laws house for a big turkey dinner, i will need to inspect the elbow and valve.

If the valve and elbow are fine with no holes or cracks? where else should i look for any vacuum leaks that may be contributing to my Po174 & Po171?

I have replaced the MAF sensor after i tried cleaning it with some MAF cleaner.

KR

[kingranch350]

Originally Posted by Breeves002

Yes, the one you have pictured is for the DOHC. I think that you bought the wrong part, and kept searching for it, that's why you kept finding the DOHC pictures.

It isn't a hard fix, just replace that elbow.

He circled it in the picture above in black (of all colors ). Usually those codes are caused by a busted PCV elbow.

I put it in blue. It is on the REAR cam cover passengers side where I indicated by the "PCV" I wrote in blue in the picture. I marked the FRONT cam cover. The back one is identical, just on the back. The V is at a 60 degree angle. One side of the V has the front cam cover on top, the other side is the rear cam cover. It's below and behind the EVR more towards the middle of the motor than the EVR, but not by much. It should have an elbow and tube going from it to the other side of the motor to the back/lower side of the intake manifold. The EVR is mounted on the intake manifold, and the EGR is on the rear of the intake manifold.

Breeves002,


Thanks for the detailed picture. I'm on my way to my in-laws for turkey. I will need to check the elbow and valve and hose tomorrow for any cracks?

Also i will be returning YF1Z-6A664-AB back to the dealer for a refund. I wonder what else may be causing my Po174 & Po171 if i don't find anything wrong with my elbow and valve?

KR

[Breeves002]

You are lucky you have a vulcan! Easy to replace the PCV valve. If you can replace it with a motorcraft part, if not, I'm pretty sure this one will work: AZ Filters/PCV Valve (PCV1260DL) | 1999 Ford Taurus 6 Cylinders U 3.0L EFI | AutoZone.com

I don't have a vulcan or have ever looked at it up close, but it seems that autozone part comes with an elbow. Inspect the hose for cracks.

If that all looks good and connected and not cracked, then hook the intake back up and we will check for vacuum leaks. You can do a cigar smoke test where you blow cigar smoke into a vacuum tube and look for where it comes out (the leak!). If we need to do that, there is a video on it on youtube.

[kingranch350]

Originally Posted by Breeves002

You are lucky you have a vulcan! Easy to replace the PCV valve. If you can replace it with a motorcraft part, if not, I'm pretty sure this one will work: AZ Filters/PCV Valve (PCV1260DL) | 1999 Ford Taurus 6 Cylinders U 3.0L EFI | AutoZone.com

I don't have a vulcan or have ever looked at it up close, but it seems that autozone part comes with an elbow. Inspect the hose for cracks.

If that all looks good and connected and not cracked, then hook the intake back up and we will check for vacuum leaks. You can do a cigar smoke test where you blow cigar smoke into a vacuum tube and look for where it comes out (the leak!). If we need to do that, there is a video on it on youtube.

Breeches,

So I replaced the pcv valve and I still have the po174 & po171. My next task will be to get some smoke to detect a vacum leak.
I will keep you guys posted on my findings.

KR