There was a recall out for leaking o-rings on the injectors for these engines. If your Dad has owned the car from new, he probably had them replaced at the time of the recall, but its worth checking out.
There is a port that can be used for a fuel rail pressure test. The pipe extends from underneath the intake plennum, and can be found close to the thermostat housing.
This picture isnt too clear, but it does show the general area that you will find the test port in.
If you can't find a manual (I got mine from ebay) you might wan't to check out alldatadiy.com I got the picture from there. There is a bunch of useful information on there, and it is almost as good as having a manual. Sometimes better.
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