Weird problem with my 87 gl wagon SPFI EA-82

I have a strange misfire or jolting problem on downhills with my subaru, it only happens during partial throttle situations between 3-4000 rpms. I have replaced practically everything ignition wise and fuel filter but still have this problem, has anybody else had this kind of problem with their subbie and if so how did u fix it?

There is an engine management computer on this car which is capable of some self-diagnosis. Some of the codes would trigger the check engine light, some won't. I'd do a search for the Ultimate Subaru Repair Manual; it should have a writeup of the procedure.

Nick

titodaf,
One of the prolems of the kind you have described may be caused by TPS (throttle position sensor). I have a similar problem at 1700 - 1900 rpm. It is just a flat spot and when I go over it the car perfoms much better.
I believe Haynes has detailed testing procedure for it. I was never able to do it: could not remove the connector. Just yesterday I noticed that there is a wire spring that holds it. So that will be my next project.

Sam