I'm working hard on a 1987 2.6l 190e. Periodically (intermittently) the
engine likes to hunt - the idle or engine speed (it doesn't care if the car
is idling or not) will jump around, as it gets worse the 02 light on the
dash will flash.
This car has had A LOT of work done to try to solve this including: new
igntion components (wires, plugs, etc), new fuel injectors, newish O2 sensor
(it's been a little while now), newish fuel pressure reg. (also been a
little while), fuel filter, etc.
Understand this only happens sometimes - which really rules out vacuum
leaks, etc. (They've been checked for anyway.) Any ideas?