Results 1 to 10 of 41

Thread: MFI engine: need to modify pump depending of cold or hot weather?

Threaded View

Previous Post Previous Post   Next Post Next Post
  1. 06-15-2023, 05:38 AM #1
    SFE
    SFE is offline
    Senior Member SFE's Avatar
    Join Date
    Dec 2022
    Posts
    275

    MFI idle problem please check video p.3 !!!

    Questions for people who have a mechanical fuel injection pump in their beautiful 911 !

    On my 911E 2.0 liters when the engine is cold I always have to pull the hand throttle a little until it warms up.
    Then, once around 80°C, I pushed back the black lever completely and it used to held idle fine around 900 rpm.

    Since the arrival of summer, once the engine is warmed up, the idle gradually collapses with some exhaust pops then it stalls if there is no hand throttle.

    I tried 2 clicks lean then 2 clicks rich on the idle screw and it was pretty much the same behavior (so back to original setting on the idle screw).
    Then I opened 1/4 of turn on the 6 screws on the throttle bodies and it holds the idle but slightly high around 1000 rpm and always some exhaust pops time by time.

    So here are my questions:

    1/ Do you also have to regularly change the pump settings to have a nominal operation?

    2/ What settings could I try to lower the idle to 900 rpm without having the engine stalling?

    Thank you !
    Last edited by SFE; 07-01-2023 at 10:27 PM.
    Reply With Quote Reply With Quote
« Previous Thread | Next Thread »

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Forum Rules


Message Board Disclaimer and Terms of Use
This is a public forum. Messages posted here can be viewed by the public. The Early 911S Registry is not responsible for messages posted in its online forums, and any message will express the views of the author and not the Early 911S Registry. Use of online forums shall constitute the agreement of the user not to post anything of religious or political content, false and defamatory, inaccurate, abusive, vulgar, hateful, harassing, obscene, profane, sexually oriented, threatening, invasive of a person's privacy, or otherwise to violate the law and the further agreement of the user to be solely responsible for and hold the Early 911S Registry harmless in the event of any claim based on their message. Any viewer who finds a message objectionable should contact us immediately by email. The Early 911S Registry has the ability to remove objectionable messages and we will make every effort to do so, within a reasonable time frame, if we determine that removal is necessary.