Hi all,
My truck (1997 f150 xl 4.2L V6) is having a loud, low-pitched rattle under my dash (or engine compartment) from the passenger's side of my cab. I just had all cats replaced & also the right intake runner mechanism. The noise didn't start until after the repairs, so I'm suspecting it's something related. I made a short video:

https://youtu.be/-FrwSnmXFQI

Many thanks for any advice!

 

Who did the work? Sounds like something is rubbing the firewall


And what do you mean right intake runner? The intake should be 1 piece?

 

It was a local mechanic. I'm not sure the approach that was used. According to the mechanic, there was an intake manifold runner valve on the left and right. I'm not too savvy, but the rubber seems to have rotted out of the right valve mechanism.

 

Have you taken it back to that mechanic and said what the heck?!

 

No, not yet. I wanted to determine if it's really worth taking it back before doing so. Since the dealerships won't touch the truck due to its age, I didn't want to risk upsetting one of the few reputable repair shops in town if it's not of much consequence.

 

that is definitely an issue.

I mean you could check on things yourself. That is weird that the dealership won't touch it. The dealerships here will work on anything, just nothing is cheap.... but that goes anywhere, and why I work on my own vehicles

 

Yeah, I'm scratching my head on why Ford dealerships won't work on my truck anymore. They claim they only work on vehicle models from within the past 10 years now. If it's an issue, I may touch base w/ the mechanic & see what he has to say. Thanks for the info!

 

Check the cat heat shields, also check to make sure none of the exhaust system is rubbing on anything.

 

Will do. I'll check out the Haynes manual & youtube to see how to access them. I've heard of metal bands being wrapped around the heat shields to stabilize them. Is this advisable?

 

To me, sounds like something is rubbing. But look at the cats. They are all right there. There are 4 of them the motor uses shorty manifolds, then the cats on the way down.