I posted a few months back about a loud noise and you guys said it was
my catallytic converter. Well, you were right, but Ford won't fix it
under warranty for just making noise. They said the engine light has
to come on specifically for that kind of emissions problem, so I've
been driving it that way. Ford suggested that it was just rattling
around down there and that they could put some clamps on it for a
price. We haven't done it yet. Tonight, we tried to leave on a road
trip and had to turn back because there was a hissing sound when we
accelerated, and we lost a lot of power. The engine sounds like it's
working hard when you first accelerate and the hiss noise is continuous
as long as your foot is on the gas.The truck got pretty hot and we had
to let it cool down before heading back home. Any chance that this is
part of the catallytic converter problem? Sounds logical to me, but I
don't know anything!!
Why not? Did you at least crawl/reach under there and see if the heat
shields are loose? Mine were, so I bought some long hose clamps from
the plumbing department at Home Depot and strapped them on.
Cost me all of $5.00
If it isn't the heat shields, then it's likely the "honeycomb" substrate inside
the converter that has come loose, and is rattling around. It's supposed to
be attached in place with some super-duper adhesive/epoxy/cement stuff.
If that lets go, the honeycomb is free to slide back and forth, bounce around,
and generally pound itself until either it's a solid lump, plugging the flow of
exhaust through the converter, or pieces of it break off and plug the converter
outlet, or the mufflers.
Engines are air pumps. Air goes in one end, exhaust comes out the other end.
If the air can't get out, it's not going to run too well, is it?
Air won't be able to get in, because it isn't coming out the other end.
Kind of like put your hand on the exhaust part of a vacuum cleaner.
The overheating is because the exhaust carries a lot of heat with it. So the
heat can't go anywhere, either.
With a little luch, you are under the emissions warranty in
which case, Ford will have to replace a defective converter.
Usually, there is a reason for this to happen. Make sure
they check the engine for fault codes or other discrepancies
that may have lead to converter failure. If there is a
problem, the replacement converter will not go very long.
If this is a high mileage vehicle where you are responsible
for the cost, you may want to consider a generic converter
from a reliable independant shop which can save you
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