[W126 Coupe] how do you adjust

[Dick Spellman]

Gary,

You need to put a fuel pressure gauge on the fuel distributor (fd).  At a
minimum you can connect to the cold start valve outlet (upper fd chamber) on
the fd to obtain overall pressure.  Ideally, you want a gauge that permits
connections to both upper and lower chambers (two hoses with a shut-off
valve on one)) so you can measure the difference between upper chamber and
lower chamber pressures (referred to as differential pressure) in the
manual.  Typical fuel pressures would be 5.3~5.4  bar overall.  When
isolating lower chamber pressure it should be approximately 0.4 to 0.45 bar
LESS than the overall pressure.  This would be your differential pressure
which is in the manual.

So, as an example upper chamber is 5.3 bar and lower is 4.9 bar,
differential is then 0.4 bar.  Without knowing the pressures it is difficult
to recommend a set of steps to remedy your problem.  Two quick questions:

1. did you replace the rubber o-ring (seal) at the base of the fd when you
swapped out?  If not, a vacuum leak (large) will likely exist where the fd
bolts down on the air flow meter housing.
2. what running conditions did you have prior to the swap?

Good luck,

Dick

On Sun, Jul 18, 2010 at 10:57 PM, Gary <garysalas at yahoo.com> wrote:


> the fuel distributor.  i put one from a donor car and need to adjust

> because the car just turns and turns   thanks for the help

>

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