Re: V8 surge problems

[Eliot Lim <eliot@u.washington.edu>]

On Tue, 26 Dec 1995 Majewskier@aol.com wrote:

> I want to run this problem by all of you cyber trouble shooters.
>  Unfortunately, as is often the case, I seem to have better luck at the
> dealer if I already know what the problem might be, especially if they can't
> diagose it via a fault readout...

i don't think that dealers know how to fix this....  maybe by now they do.
 
> My '90 V8 "surges",  for lack of a more exact term.  At part throttle. ie.
> when cruising at a steady highway speed, I can definitely notice a somewhat
> cyclic increase/decrease  in engine output.

> Since writing the above, I am wondering if I am experiencing a bad Ox sensor
> and if I am noticing the lambda? rich/lean feedback loop? 

my car did this too for a while and the problem went away when the OXS
was replaced as part of the 60K service.  actually i had all the various
pieces of the 60K done at slightly different times, so i know for a fact
that a new OXS fixed the problem.

> The car only has
> thirty some thousand miles, but it is over five years old. It has had all
> dealer related service performed before I purchased it, including the 30K
> tune.  Could that expensive little Bosch piece be failing already?  

perhaps.  i also think that the way the exhaust system was designed
tends to exaggerate the problem.  the v6 cars use 2 oxygen sensors to
get around this problem.
 
> Also, I am also paranoid about the Seattle-area (m)ethanol gas from Nov to
> Feb.  Especially because of this, I plan on changing the fuel filter soon,
> since is not part of any dealer service, but I think these two things are
> coincidental.

i got my fuel filter changed recently with no noticeable effects.



eliot