I was reading about modifying the stock TBI fuel pressure regulator to be adjustable and wondered if the '91 3.1 MPFI fuel pressure regulator was the same? Can I do the same thing to it?

 

You can put a penny under the diaphragm, but unless you have mods what's the point..

 

Cause the car is running pretty fat and I figured if I can do that same mod I can dial it in to where it needs to be (factory psi) instead of spending the money to buy a new stock one or aftermarket for that matter. Just want this engine to last and run well 'till the spring and I don't want to put to much money into it. Already did a complete tune up including o2 sensor and she still runs fat. If I could get away with a "free" afpr then its well worth it. Otherwise I guess I will just shell out the cash for a stocker thats only going to be used for a few months. Seems like a waste.