> -----Original Message-----
> Intake reasonably cool. But exhaust manifolds very
> hot, too hot to hold.
They're made of iron and there's fire inside them when the engine is running
so they retain heat longer. Aside fron the catalytic converter, they'll be
the hottest parts of your engine/exhaust system.
> I waited a bit until stuff cooled down to touch.
> Then I felt cat. It was still hot to touch. But rest
> of exhaust -- manifolds, y-pipe, pipe in front and
> behind cat towards muffler were really cool.
> Is this normal? Should the cat be that hot while
> everything else touching it is super cool?
Yes. The cat's function is to get hot enough to react to the exhaust gasses
and reduce emissions. It's not just a hollow pipe so it will retain heat
longer than anything else. That's why they usually have heat shields around
it. The other parts are thinner and dissipate heat much faster.
>(BTW...I just cut
> off pigtail to 02 sensor. Seems to have no effect on
> my engine behavior at this point.)> Thanks. Will
I hope you did that just to remove it and replace it with a new one. If you
didn't replace it you have just duplicated the behavior of a bad O2 sensor
by cutting the wires. As I suggested a few days ago, replace the O2
sensor. It's cheaper than a catalytic converter. Even if that's not the
ultimate solution it may improve your performance and mileage anyway once
you get the truck running again.
When you go to replace the O2 sensor, disconnect the battery first so the
computer will be reset when you start the truck. This is important!
RayB
http://www.dragtruk.com/ENTRIES/20KM1FD2KWBP.html
This archive was generated by hypermail 2b29 : Fri Feb 06 2004 - 11:46:01 EST