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Old 10-07-2016, 12:04 AM
Alec300SD Alec300SD is online now
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Join Date: Nov 2013
Location: San Mateo, CA
Posts: 1,163
Quote:
Originally Posted by kahlil88 View Post
I've been meaning to tackle the lift pump for awhile. Where is the pressure relief valve?
The overflow/pressure relief valve is located on the engine side of the IP at the of the clear hardline.

It's just a hollow bolt with a ball and spring that allows the fuel return to the tank when the internal IP pressure is too high.

Engine performance can suffer if the the base fuel pressure is too low (under 1 bar for stock IPs).
Some overflow valves can be rebuilt if the spring has fatigued.

Greazzer sells stronger rebuilt Performance Overflow Valves (or just the springs at this time, IIRC).
I have purchased two of the rebuilt overflow valves and installed them in my cars. They made a noticable difference.
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