Go Back   Ford F150 Forum - Community of Ford Truck Fans > Pre-1997 F150 > 1987 - 1996 F150
Sign in using an external account
Register Forgot Password?


Welcome to F150 Forum!
Welcome to F150 Forum,

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!


Reply
 
 
 
 
Thread Tools Search this Thread Display Modes
Old 02-01-2013, 04:54 PM   #1
Senior Member
 
Ford 4x4's Avatar
 
Join Date: Aug 2012
Location: MN
Posts: 1,526
Mentioned: 0 Post(s)
Thanks: 5
Thanked 43 Times in 42 Posts
Feedback Score: 0 reviews
Default Mystery Pipe/tube question

Hey guys, so the other day I cut the cats off my 89 f-150 5.0. I was cutting off the cats, and right behind the second cat (resonator maybe) there was a metal tube that was welded into the exhaust....

I cut it off from the exhaust, and never welded it into my new exhaust, it just hangs by it. It looks like it goes up to the back of the motor on the passenger side, but I did not follow it anymore than that.

I was just curious what this tube was, and I do not have pics

PS- I drove the truck a few miles home after I did the exhaust. The next day it was very cold -15 at least. The check engine light stayed on all day. I put oil and antifreeze in so I knew those were good. The truck runs great when the light is on... what would cause this.

Finally the check engine has come on and off for a few years now. It only happens when it is cold (maybe below 30) and only flashes on and off when you acellerate. I thought it was an intake gasket, so I put stop leak in and it still does it. Any ideas? Thanks guys
Ford 4x4 is offline   Reply With Quote
Old 02-01-2013, 06:32 PM   #2
Senior Member
 
Ace12ace12's Avatar
 
Join Date: Feb 2011
Posts: 172
Mentioned: 0 Post(s)
Thanks: 3
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Default

I think it's for the egr valve.
Ace12ace12 is offline   Reply With Quote
Old 02-01-2013, 06:53 PM   #3
Senior Member
 
13Harleyfan's Avatar
 
Join Date: Aug 2012
Location: El Paso Texas
Posts: 1,617
Mentioned: 3 Post(s)
Thanks: 80
Thanked 162 Times in 132 Posts
Feedback Score: 0 reviews
Default

I believe that tube feeds back to the air pump. Someone correct me if I'm wrong. As far as the check engine light,anytime you start disconnecting or removing things that are related to emissions it's not unusual to see the light come/stay on. It might feel like it's running fine but you are probably wasting fuel.
13Harleyfan is offline   Reply With Quote
Old 02-01-2013, 07:32 PM   #4
Senior Member
 
Moose_God's Avatar
 
Join Date: Jan 2012
Posts: 376
Mentioned: 0 Post(s)
Thanks: 2
Thanked 13 Times in 13 Posts
Feedback Score: 0 reviews
Default

It's the AIR injection tube...I broke mine while removing it to install headers....got a new tube from rock auto but can't seem to find anyone who sells a weld-in bung for the exhaust side.
Moose_God is offline   Reply With Quote
Old 02-01-2013, 08:09 PM   #5
Senior Member
 
Ford 4x4's Avatar
 
Join Date: Aug 2012
Location: MN
Posts: 1,526
Mentioned: 0 Post(s)
Thanks: 5
Thanked 43 Times in 42 Posts
Feedback Score: 0 reviews
Default

Sweet, but I don't actually need it do I? I know on my 4.9 I had the local muffler shop put new exhaust on it and he just left it disconnected, I have not had any CEL or performance problems
Ford 4x4 is offline   Reply With Quote
Old 02-01-2013, 09:47 PM   #6
Senior Member
 
Join Date: Oct 2010
Location: Upstate, New York
Posts: 128
Mentioned: 0 Post(s)
Thanks: 0
Thanked 2 Times in 2 Posts
Feedback Score: 0 reviews
Default

Its the egr tube it goes into the crossover pipe on the back of the heads which is fed cool air from the air pump. Just remove the tube, crossover tube, plug the vacuum line on top and delete the air pump. If your state requires emissions then you must leave that stuff on and replace the the egr tube. It sticks into a rubber tube behind the motor and then welds into the exhaust pipe before the cats but after the 02 sensor. Make sure if you delete the air system to plug the holes on the back of the heads.
snipe1605 is offline   Reply With Quote
Old 02-01-2013, 10:05 PM   #7
Senior Member
 
KentuckyCountryBoy's Avatar
 
Join Date: May 2010
Posts: 471
Mentioned: 0 Post(s)
Thanks: 1
Thanked 3 Times in 3 Posts
Feedback Score: 0 reviews
Default

Quote:
Originally Posted by snipe1605 View Post
Its the egr tube it goes into the crossover pipe on the back of the heads which is fed cool air from the air pump. Just remove the tube, crossover tube, plug the vacuum line on top and delete the air pump. If your state requires emissions then you must leave that stuff on and replace the the egr tube. It sticks into a rubber tube behind the motor and then welds into the exhaust pipe before the cats but after the 02 sensor. Make sure if you delete the air system to plug the holes on the back of the heads.
No, the EGR connects the lower intake on a 5.0 or the exhaust manifold on a 5.8 (idk about 4.9) to the EGR valve on the upper intake, right behind the throttle body. The piece the OP is refering to is the AIR pipe. If he deleted the cats, I'd just delete the tube too. Unless the truck has two O2's the exhaust mod should have nothing to do with the CEL.
__________________
______________________
- 2001 F-150 XLT 4x4. 5.4, auto, manual t-case. Mostly stock for now...
- Mods- Pioneer single-din, 16in Eagle Alloys w/265-75's. - Future- Pioneer double-din, 2-10" subs, dual exhaust, torsion key crank.
- 1992 F-150 FlareSide - Lives again - 5.0 H.O., 31x10.50's, true duals with glasspacks
KentuckyCountryBoy is offline   Reply With Quote
Old 02-01-2013, 10:07 PM   #8
Senior Member
 
Ford 4x4's Avatar
 
Join Date: Aug 2012
Location: MN
Posts: 1,526
Mentioned: 0 Post(s)
Thanks: 5
Thanked 43 Times in 42 Posts
Feedback Score: 0 reviews
Default

Quote:
Originally Posted by KentuckyCountryBoy View Post
No, the EGR connects the lower intake on a 5.0 or the exhaust manifold on a 5.8 (idk about 4.9) to the EGR valve on the upper intake, right behind the throttle body. The piece the OP is refering to is the AIR pipe. If he deleted the cats, I'd just delete the tube too. Unless the truck has two O2's the exhaust mod should have nothing to do with the CEL.
I did delete the cats, how do I delete the tube? where should I block the tube? The truck just has 1 02 sensor.
Ford 4x4 is offline   Reply With Quote
Old 02-01-2013, 11:14 PM   #9
We'd do it
 
Just call me Sean's Avatar
 
Join Date: May 2008
Location: Orlando,Fl.
Posts: 31,039
Mentioned: 2 Post(s)
Thanks: 29
Thanked 360 Times in 320 Posts
Feedback Score: 1 reviews
Send a message via Yahoo to Just call me Sean
Default

EGR on the 4.9 connects to the rear exhaust manifold.

That is the air injection pipe, and without cats it isn't needed. It also won't cause a check engine light just being disconnected there. Just remove the rest of it. Check for codes.
__________________
Quote:
Originally Posted by Early Cuyler
Fights begin, fingerprints are took, days is lost, bail is made, court dates are ignored, cycle is repeated.
Just call me Sean is offline   Reply With Quote
Old 02-02-2013, 07:01 PM   #10
Senior Member
 
Join Date: Oct 2010
Location: Upstate, New York
Posts: 128
Mentioned: 0 Post(s)
Thanks: 0
Thanked 2 Times in 2 Posts
Feedback Score: 0 reviews
Default

Oh yes your right its the air tube, but to delete the system you need to delete the crossover tube on the back of the heads and delete the air pump. It wont set off the cel but you will get a code for the air system not working. If you dont remove it all you will have an exhaust leak there.

Last edited by snipe1605; 02-02-2013 at 07:03 PM.
snipe1605 is offline   Reply With Quote
Old 02-02-2013, 07:01 PM
 
 
 
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


 

The Mustang Source
All times are GMT -4. The time now is 07:06 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.5.2
Copyright 2006 - 20011 F150forum.com
This site is in no way affiliated with the Ford Motor Company.