The Central Hub for DSM Community and Information

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. This is where the DSM platform history is documented and archived. Log in to help us in our mission, and to remove most ads from the browsing experience.

Adjusting fuel pressure with a FPR. Gota question

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

-DSM2NR-

15+ Year Contributor
602
12
Dec 9, 2005
Tucson, Arizona
Just got done installng my Fuel Pressure Regulator and I had a question. Should I adjust the fuel pressure with the vacuum hose connected or not? I've noticed that with the vacuum hose connected, and the car running the fuel pressure drops quiet a few pounds. So, should I adjust fuel pressure with or without the vacuum hose connected?
 
disconnect hose and close off the end of the hose itself(put your thumb over it) then set it. After it is set, reconnect the hose and the pressure will drop down.
 
Once you set the fuel pressure with the line disconnected and capped, it is set. Put the line back on, fuel pressure will drop and you are done. The pressure is set with the line off, so you would leave it alone after reconnecting.

Yes, this post is correct. :thumb:
 
Found this thread on a search, I was wondering the same about the setting the fpr thing, good answer.
But my question is, what would be a 'ideal' fuel pressure to set with the vaccum line removed, before reconnecting? or is it goning to differ from the setup your running?
Thanks.
 
Found this thread on a search, I was wondering the same about the setting the fpr thing, good answer.
But my question is, what would be a 'ideal' fuel pressure to set with the vaccum line removed, before reconnecting? or is it goning to differ from the setup your running?
Thanks.

Base fuel pressure for a 1G is 37 psi. It does not change regardless of your setup. So disconnect the vacuum line to the FPS and cap the end. Adjust fp to 37 psi. Reconnect vacuum line. The fuel pressure will drop relative to how much vacuum you have at idle (it drops 1 psi for every 2inHg). This is normal and expected. You are done.
 
Add Value - Be Respectful - No Trolling - No Misinformation - Participate Often!
Support Vendors who Support the DSM Community

Latest Classifieds

  • For sale 2g 2G Power Window Switches ( tested and hardware included )
    2G Power Window Switches $55 + shipping and paypal fees* Tested 6/2/26 * Hardware included *...
    • jersygsx
    • Updated:
    • Expires
  • For sale VIRGIN 4G63 6-BOLT TURBO HEAD
    Came off a virgin stock AWD Auto 1G DMS (91), also have matching block and crank which are also...
    • The_Partout_Spot
    • Updated:
    • Expires
  • For sale 1G DSM 4G63 6-BOLT TIMING COVER
    Used, see condition in photos. Buyer covers shipping / fees.
    • The_Partout_Spot
    • Updated:
    • Expires
  • For sale Garage clean out
    Changing setups on the car and getting rid of some stuff as well that's been laying around. Will...
    • 92GSXtacy
    • Updated:
    • Expires
  • For sale 4G63 Griffin intercooler cores
    Griffin intercooler cores. Top to bottom flow. High cfm and heat transfer. 24x8x2.75 and...
    • Galant665
    • Updated:
Back
Top