I am having fuel pressure problems, fuel pressure is jumping back and forth by about +- 2 psi from 42 psi. and im thinking about getting a Adjustable Fuel Pressure Regulator. most of which use the stock FPR diaphram.. and i don't know if thats a good idea with mine, being it already has 218K miles on it. or does the stock diaphram pretty much last a long while. or does it only need to be replaced when it leaks?? sorry i really don't know much at all about the diaphrams about these things..

 

They can last quite awhile..but at that mileage I would recommend to change it if you are planning to install an adjustable housing.I paid around $40 when I changed the diaphram on my T/A a couple of years ago.Mine was obviously bad but at your mileage you could see an improvement in how the car runs.

 

I have the same problem with my fuel pressure also, I thought it was the gauge so I had it replaced. the new one dont do it as much but still flucuates +-3 psi. My diaphram was stuck to the stock regualter and I had a pain getting it off. I did tear it in a few places but at the time I had to put it back in. Where can I get a new diaphram for it

 

AutoZone sells them. Only around $20 if I'm not mistaken.

 

And the problem may not be so much with the diaphragm, but with the disc valve and seat. The seat and disc are highly polished to provide a tight seal (which is far better than a loose walrus). You'll get a new disc with the replacement diaphragm, but should closely inspect the seat in the lower half of the regulator body with a magnifier for any signs of wear or damage.