[V8] V8 surging problem continues

[Ed Kellock]

Just off the top of my head....

Vacuum leaks can also cause this.  There are a few common places to
find vacuum/breather hoses.

Under the air cleaner cover, there is a breather hose that goes from
one side to the other.  There is another that goes from the back of
the driver's side valve cover down to the block.  There's another
small short one at the front of the driver's side valve cover that
goes down into the abyss.

There is a vacuum line that circles around the intake hole at the back
of the top of the intake manifold (you have to remove the bottom of
the air cleaner box to find it.  Just next to its passenger side end,
there's another vacuum hose that goes to the climate control system. 
(This is the one that I just found a large tear in last week.)

There's a small one that runs from the fuel pressure regulator to the
intake manifold.  This is right on top of the intake manifold.  There
are two more that go from the butterfly plate at the front of the
engine to the carbon canister.

Some have bought a 4-wire ox sensor and ran the separate external
ground to the bolt that secures the cruise control diaphram apparatus
to the back of the top of the engine block.

Remove and clean the connectors for the throttle position sensor. 
Also check the connections for the intake air temp sensor.  If they
are soldered, you may consider putting solder gun to each to melt the
solder and let it recure to refresh the connection.  If they're not
soldered, then unplug each and clean the connection.

Check to see if the surge is present when the climate control system
is set to OFF.  There's a way the CC controller can cause a vacuum
leak too.

Ed

On Thu, 23 Dec 2004 09:00:46 -0500, aukdav <aukdav at mail.ccsdana.net> wrote:
> Having some teething problems with my recent find.  1990 V8Q  When I picked it up it had moderate surging problem.
> 
> A read of archives told me 02 sensor was to blame.  Changed the 02 sensor with the tried and true Bosch generic.  No improvement.
> 
> Checked the #5 fuse, it was fine.
> 
> Changed the fuel filter, no improvement.
> 
> Changed the NTS sensor on the back of the left head.  No improvement.
> 
> WOT gives good smiles.
> 
> What is the next step?
> 
> Thanks,
> Dave
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