Go Back   F150online Forums > Powertrain & Mechanical > Exhaust & Intake Systems
Sign in using an external account
Register Forgot Password?
Register Photos Vin Decoder FAQ Members Search Today's Posts Mark Forums Read Vendor DirectoryGarage

Welcome to F150Online Forums!
Welcome to F150Online.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community 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 fast, simple and absolutely free so please, join the F150Online Forums community today!





Reply
 
 
 
 
Thread Tools Search this Thread Display Modes
  #1  
Old 04-04-2011, 03:09 PM
Senior Member
2004 Ford F-150
 
Join Date: Dec 2006
Location: SOVA
Vehicle: 2004 Ford F150
Posts: 266
Best way to find exhaust leak?

Ive got an exhaust leak on my truck and cant seem to figure out where from. The motor and cats were replaced recently. The noise is most noticible when starting the truck with the window open. I would think it would be the exhaust manifold as that should have just been bolted down tight with a new gasket. Plus it doesnt sound like a manifold leak, its not really audible in the cab like manifold leak ive heard. So whats the easiest way to determine the leaks source?

Thanks in advance for any help, i hate an exhaust leak. Makes me feel like im driving a old beater truck
Reply With Quote
  #2  
Old 04-04-2011, 05:28 PM
Senior Member
2006 Ford F-150
 
Join Date: Aug 2008
Location: Douglasville GA
Vehicle: 2006 Ford F150 XLT
Posts: 4,773
Look for black marks.
Reply With Quote
  #3  
Old 04-04-2011, 10:52 PM
Senior Member
Garage is empty, add now
 
Join Date: Oct 2009
Location: Missouri
Vehicle: 2006 Ford F250
Posts: 6,172
Start the truck cold, and feel around all the seams. You will feel a leak. Black marks will also show.
Reply With Quote
  #4  
Old 04-05-2011, 12:23 PM
Senior Member
Garage is empty, add now
 
Join Date: Dec 1999
Location: California
Posts: 1,181
Yup, black soot marks and with the truck running, have someone place a thick rag/towel over the tailpipe restricting the flow...the sound will pop out (so to speak)
__________________
Member: Never trust a person over 40 who drives a Chevy club
Flatheads ain't so bad!
Certified backyard mechanic I & II

Reply With Quote
  #5  
Old 04-05-2011, 05:25 PM
Senior Member
1975 Ford F-100
 
Join Date: Apr 2007
Location: Ohio
Vehicle: 1996 Ford f150
Posts: 504
Check the bolts on the manifold again. For headers at least, you snug them up after install, drive i little bit and get everything seated, then tighten them down to spec.
__________________
Quote:
Witty73: Thats not something you hear out of a 79 F 350 owner often...."dang, this thing sits too high!"
Open Headers, F100 Sand Dune
F100 In-cab
Reply With Quote
  #6  
Old 04-05-2011, 05:48 PM
Senior Member
Garage is empty, add now
 
Join Date: Jan 2007
Location: Marysville, Washington
Vehicle: 2006 Ford F150
Posts: 328
Hold a piece of pvc pipe or hose up to your ear and move the other end around where you suspect the leak may be.
__________________
2006 SCAB XLT 4x4
Drive train Yukon 4.10 gears front and rear, Detroit Truetrac LSD front and rear, Mag-Hytec diff cover - Performance Airforce One 3.5" intake, Magnaflow 94306 high-flow cats, Corsa sport SISO , SCT w/tunes from Troyer, e-fans - Suspension Rancho 4" lift and 9000XL shocks, Toyo 34" (285/75/17) MT on ATX Storm wheels (17x8) - Other Code alarm w/remote start, Line-X in the bed, Bak-Flip G2, Passport SR1 detector, KC Slimlites behind grill
Reply With Quote
  #7  
Old 04-06-2011, 11:50 AM
Senior Member
Garage is empty, add now
 
Join Date: Mar 2007
Location: NC
Vehicle: 2005 ford f150
Posts: 377
Hook up a shop vac or blower to your exhaust pipe and turn it on. The engine is off. Spray a soapy water around every possible leak point. That's how I found my manifold gasket leaking.
__________________
2005 FX4 Screw 4x4 3.55 LS 5.4
2013 OEM 20's 275/60/20 Nitto Terra's
Gotts Intake
Daystar budget lift
Firestone Air bags
Roush Offroad Exhaust
Reply With Quote
  #8  
Old 04-06-2011, 12:44 PM
Technical Article Contributor
Garage is empty, add now
 
Join Date: Oct 2005
Location: MI
Vehicle: 1998 Ford F150 5.4L 4X4
Posts: 25,560
Quote:
Originally Posted by jaws12 View Post
Hook up a shop vac or blower to your exhaust pipe and turn it on. The engine is off. Spray a soapy water around every possible leak point. That's how I found my manifold gasket leaking.
Smart guy

That's what works best. I use compressed air myself @ about 15-20 lbs, - only because I have the fitting reducer for the tailpipe. I know those Rigid shop vacs will plug right tho lol.

Yep, soapy water on the seams reveals all.
Reply With Quote
  #9  
Old 05-31-2011, 07:47 AM
Member
2000 Ford F-150
 
Join Date: Apr 2011
Posts: 38
Quote:
Originally Posted by jbrew View Post
Smart guy

That's what works best. I use compressed air myself @ about 15-20 lbs, - only because I have the fitting reducer for the tailpipe. I know those Rigid shop vacs will plug right tho lol.

Yep, soapy water on the seams reveals all.
I'm suspecting a small exhaust leak, because after driving a while with blower on Low I'm getting a headache. With blower on High it doesn't bother me. My passenger side manifold has bolts into the head instead of studs and nuts, so it appears someone had some problems with it at some point. I can't hear any obvious puffing. I tried feeling around the manifold with the truck running, and I think I can feel a small leak, but it's hard to tell with all the air flow in that area with the fan running. I tried testing the air for CO with a battery powered home CO monitor, but it didn't show any reading above zero, so apparently it isn't really bad.

jbrew - Where did you get the fitting to connect the compressed air to the tailpipe? This seems like a good way to get the exhaust system pressurized. Also, I have a dual exhaust - any good way to plug the other side? I was thinking of using a big sponge with a plastic bag wrapped around it.
Reply With Quote
Old 05-31-2011, 07:47 AM


 
 
 
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 On
Refbacks are Off


All times are GMT -4. The time now is 07:29 PM.


 
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company
Contact Us Advertising Privacy Statement Terms of Service Jobs Forum Text Archives
Emails & Contact Details