80 won't rev...what happened?

[EBavely]

Hello all...

Another strange one on the way to work this morning.  My 88 80 fwd (2 liter
4cyl, but that doesn't matter for this story) was cruising along just fine
at around 80 mph (going with the rush hour flow) when suddenly it seemed to
lose power and bog down when I got on the throttle.  Seemed like it wouldn't
make more than about 3500 rpm.

I got off at the next exit and left the car running.  My initial thought was
that a sparkplug wire had popped off or that there was a restriction in the
fuel system (just filled up this morning) somewhere.  The car seemed to idle
fine though.

I heard hissing from under the car, so I got out the junkyard dropcloth
(gotta have one in the trunk just in case, right?) and checked it out.
Seemed like the hissing was coming from a previous exhaust repair just
beyond the cat.. the type where the PO used some kind of bolt-on "splice
sleeve" rather than welding.  Hmmm... exhaust restriction?  plugged cat all
of a sudden? Did the timing suddently jump a tooth?

Continued on the way to work... still same behavior.  Pulled over again and
looked at the rear muffler... seemed to have an unholy crack or dent in the
side of it.  Never noticed that before and the car isn't loud at all... more
hissing.  By this time, I was kind of late to work, so I limped back on my
way taking the backroads...thinking to myself what I'd do to get home
tonight.

Turning up the drive to work, there was a clunk from under the car and the
engine returned to normal.  Power came back and the engine wanted to rev
again.  Bizarre.

I'm thinking maybe a part of the aging exhaust had dislodged and got stuck
somewhere in the system and caused a restriction.  That would kind of
explain the hissing up front (increasing the pressure upstream and forcing
more air out of the bad repair) and the lack of power.  Maybe the engine
couldn't breathe and was being smothered...

Anyone ever seen this before?  Any other ideas?

Looks like I'm exhaust shop bound...to see what my options are for a $500
car with over 200k miles.  The stock exhaust would probably cost more than I
gave for the car.

Maybe I'll ask the guys to get creative and do one single side pipe out the
passenger side ahead of the rear wheel...oh wait, this is a daily driver.

Elliott Bavely

86 4ktq
83 CGT
81 Coupe ITB
88 80 Fwd
Other varied VAG products.