The Oldsmobile Connection

[justinwebb]

so my olds is losing lots of power.....after i drive it for a while i push on the gas and it is very slow to acclerate and sometimes it wants to die......i am thinking maybe its the exaust system is going bad......any other ideas???

[GraveReaper0]

Is the engine breathing fine?

[88 Coupe]

Hi justinwebb, hello all

Quote: ................ after i drive it for a while i push on the gas and it is very slow to acclerate and sometimes it wants to die ................. maybe its the exaust ..............

Not the exhaust, because it doesn't occur right away.

Fuel filter would show up, under load, at higher RPM and would recover after you lifted the gas pedal.

Try driving it without the gas cap. It's rare but the cap can cause the problem you described.

If not, it's probably in the electronics and someone else will jump in.

Regards, Norm

[Turbocharged400sbc]

there is the very real possibility of the fuel fressure being low due to a clogged fuel filter this will require driving the car with a fuel pressure gauge on it at the problem time.
however if your Catalytic converter has broken it may clog up the exhaust gas flow path and reduce flow to check fer this just whack the cat case with a hard rubber mallet and listen for it rattling-to test for this an exhaust backpressure gauge installed in the O2 sensor port with show how bad it is as this problem gets worse as the cat gets hotter
a quick way to tast this is to unbolt the downpipe from the rear exhaust manifold and drive it (will be loud but will drive normally if the cat/exhaust is the problem)
hope you nail this gremlin good luck
schlim

[OldsGuy]

I had heard about catalytic converters failing like that but only when they were first being used on cars in the early days. Didn't know they could still fail that way. That would be a problem though. That's why I drive a car that doens't require one :D . Not really, my '76 Omega has a cat on it and my wife's Buick has one. But the Delta? NO WAY :P

[Turbocharged400sbc]

the earlier cats (pellet type) had a problem with the cage that held the pellets it would brak and clog up the muffler with pellets or it would just clog up with carbon (from what i have heard due to eddy currents that let the carbon settle in spaces around the little balls of catalyst) the newer cats have all been triangular/octogonal matrix monolithic cats that have straight passages to reduce the eddy's that caused earlier problems. the monolithics are much more resistant to cloging (though a few passages with manufactured defects might clog) the problem is (triangular cats are stronger) that the monolithe catalyst must sit inside a "blanket" inside of a converter case then the cage is crimped to hold the matrix in place during this there is the possibility that it cracked though usually it's the constant thermal cycling of the platnium/paladium/rhodium ceramic matrix with the thin metal substrate (that is formed into the triangular or hex/oct pattern and the ceramic catalyst applied to it) that will eventually do it in if your lucky the outer rows will break and the monolith will just be able to rattle around and make noise if a chunk breaks off it can clog the outlet and cause problems but then hit a bump and cause no problems then hit another bump......you see where this is going, and people bitch about how long it takes to diagnose their problem......if they describe it right...
hope this learns ya a bit more about these emmissions devices
schlim

[OldsGuy]

thanks, I appreciate that. Lucky the '76 is still on the original cat and that will go when the 455 is swapped in. I always hated that weird smell they put off :x