Yesterday while driving and shifting into 4th, I heard a noise coming from about where my tranny sits. Immediatly I thought something in the drivetrain went out, so I pulled over to take a look under the truck and saw the problem. There's a metal looking hose that came unattached from one of my catalytic converters (because of rust), and that's causeing an exhaust leak. my question is, what the heck is the purpose of this thing? And, do I need to worry about fixing it?





1988 F-150 XL - 5.0 - 5 Speed

 

Is it the air pump hose?

 

could be EGR related. the line that attaches the air pump to the cats, it helps reduce emissions. im not 100% sure, but ive heard that cats can get clogged easier if you disconnect that hose. then again, i could be wrong

 

Yup, EGR tube. It will make noise from flopping around and excess exahst noise. You can weld it back up or take it to a shop to weld it up. Mine cost $10 to have fixed at a local muffler shop. Now that I have a mig welder, I could weld it up in 5 minutes.

 

Mine did the same thing...air pump hose/ hard line portion rotted off and was hanging, with a cruddy exhaust leak. The replacement hose was $40 from my local dealer. It comes with the tiny clamps and the correct bends and everything. Kinda pricey for a 1/2" metal tube but it bolted right up once the remainder of old pipe is removed. Don't bother even looking in that area unless the exhaust is cold Fore-arm skin burns easily.