I had an issue recently with my 1996 f150 4.9 that I posted about. It had a leak at cylinders 1 and 2 so I had the head re-machined and had them install new valve train which I re-installed into the truck. The hardest part of the entire job was re-installing the Exhaust manifold-to-EGR tube. because the tube is not flexible, it was a bear trying to align the large nuts on each end of it. The part I am talking about is shown in the first image, part #9:
As you may be able to tell, I drew two little tubes coming off of the main pipe, because that's how it really is. the main pipe is maybe 1.25" diameter and the two metal tubes that are welded on are maybe 1/4" in diameter. Then the two smaller tubes each ha ve a 6" rubber tube attached, which then connect to the EGR transducer. Shown in image #2. So, the main large tube connects the exhaust manifold to the EGR valve. There are two smaller tubes that lead from the main tube to the EGR transducer. I believe that in a moment of lack of patience on my part that while re-installing this tube, I most likely bent one of the smaller tubes enough that their is now a vacuum leak.
The engine runs great, but I am now throwing codes P1506 (idle air control overspeed), P0174 (bank 2 too lean), P0171 (Bank 1 too lean), P0136 (O2 sensor lean), and P0141 (O2 sensor lean). All of these codes are caused, I believe, by a vacuum leak, and I believe it from the tube from hell.
My question: is there a replacement for this tube that is flexible? I can't find a new part anywhere, and going to a junkyard to fetch one out of a truck would take hours as half the engine would need to be torn apart. I don't mind spending the time on my own truck to re-install one, but I can't find one or a suitable replacement anywhere. Any ideas? TIA

Edit: BTW, the vacuum on my cheap little phone app shows the vacuum at 26.2 at idle, which i think is still pretty good, but i don't know what the spec is. Also, the truck revs pretty high at idle - like 1100 rpms. truck runs great despite the leak, but would still like to fix it.

 

Looked at numerous sources after google search for 9D477 4.9 96 Ford.

Including Dorman's site (no part for 96 4.9)

Looks to be 96 part only, perhaps because of OBD II.

Perhaps Number Dummy could locate a NOS one for you.

 

Those sample tubes are connected to the DPFE sensor by the silicone tubes, they do not go to the intake. I seriously doubt if one were cracked that it would cause a high idle as you imply. But, it could trigger lean codes since they would allow air into the exhaust upstream of the O2 sensors. I would also think you would see EGR flow related codes if your theory of a cracked sample tube(s) was true.

The Ford part number for the one year only EGR tube is F6TZ-9D477-E if you feel compelled to replace yours. Tasca Ford shows they have one: https://www.tascaparts.com/oem-parts...ube-f6tz9d477e

I would call to verify, but also caution you to look a bit deeper to locate an intake vacuum leak. Your phone app is most likely lying to you. There is no way the idle vacuum is "26.2". I am not aware your powertrain control system can even measure true manifold vacuum.

Edit: Correct part number is F6TZ-9D477-P. And may be unobtanium...

 

I looked at Tasca & drilled down from a 96 4.9

https://www.tascaparts.com/auto-part...ion-system-cat

I think what you show is a 5.8 or 5.0

There seem to be plenty of those.

Could be wrong, frequently am.

 

You are 100% correct. Good catch, I did link to the wrong EGR tube. The correct part number is in the edit above. Could be tough to find, and I still think may not be necessary.

 

Yeah, I feel it's not either, but the damn things crack at the most inopportune times.

If it still has that mesh cover, it might not be showing.