My MPG suddendy fell almost 90%, and then another 30% with the next
The dealer pretty much hinted that they would rip me off, since my car
is OBD-I (88' injector V6 Olds).
What I'm looking for is personal history of people who dealt with a
problem like this and what was the final cause that got the car back
from the dead.
Basically, I'm looking for pointers to start self-diagnistics.
In my case - air filter is clean, spark plugs/wires are relatively
fresh, thermostat & engine coolant sensor are relatively new, and
report ok on the dash.
I do know that the cat is somewhat clogged, but in the past in the
similar condition it didn't cause the MPG drop to such extent.
Car rides very smooth, which probably means that there's no rust on
In the essence, I'm close to be making only 1/3 of normal mileage at
this point, highway or not.