Results 1 to 8 of 8

Thread: Help! EMI & RFI?

  1. #1

    Default

    After a few minutes of idling, I loose RPM, TPS & WBO2. The ECU then cuts on & off then it completely turns off. I'll leave it off for a hour, let it cool down, and the cycle continues. It only seems to happen when warm, but I'm not sure if it has anything to do with the problem though.

    My setup: Magnetic pickup distributor (No, I do not want to buy a dual sync), Coil driver, 84211 rotor, MSD Super Conductor wires, ACDelco R43TS plugs, Coil = SUM-850500.
    What I have tried: New plug wires, original pro billet rotor, smaller air cleaner, different tune, grounded the coil driver and ECU to the firewall.

    Datalogs & Tune:
    https://www.dropbox.com/s/fjurhlmiyv...e%202.PNG?dl=0
    https://www.dropbox.com/s/f66pmmrhuy...pture.PNG?dl=0
    https://www.dropbox.com/s/o9he3xbjdxps988/Log12.dl?dl=0
    https://www.dropbox.com/s/5cbuhae0nz...RF%205.dl?dl=0
    https://www.dropbox.com/s/t29abn4qg7....5.sniper?dl=0

    UPDATE: I solved the issue and wanted to post it for anybody who has similar issues. There are numerous things that Holley never mentions for using a magnetic pickup distributor:
    1) Make sure your Reference Angle is 10° more than the max timing the engine will see.
    2) Set your Minimum Signal Voltage to 0.65V and your Filtering to High.
    3) Try using the stock non-adjustable rotor. For some reason the MSD 84211 adjustable rotor can cause issues.
    4) You need to have a CS alternator. A SI alternator was not built to work with EFI.
    5) Make sure no spark plug wires are touching your air cleaner.
    6) Also make sure you have quality plug wires. MSD Super Conductors have the lowest EMI.
    Hope this helps. I've read numerous threads about people having similar issues, and I feel that Holley could better themselves if they informed people about this.

  2. #2
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    19,283

    Default

    Thanks for updating this thread. It's very helpful to others to read resolutions to problems.
    May God's grace bless you in the Lord Jesus Christ.

    '78 BRONCO: 508" stroker, TFS heads, 11:1 comp ratio, Dominator MPFI & DIS, cold air induction, Spal dual 12" fans/aluminum radiator, dual 3" exhaust/Magnaflow mufflers, Moroso vacuum pump, Accusump, engine oil & trans fluid coolers, 100HP progressive dry direct-port NOS, A/C, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, 3:1 Atlas II, modified Dana 44/60-lockers-4.10s, hydroboost/4-disc brakes, ram-assist/heim joint steering, Cage long radius arms, traction bars, 4" Skyjacker lift, 35" mud tires

  3. #3

    Default

    Can you further explain some of this? Thanks.
    Magnetic timing why?
    Alternator why?
    Where did you get this from?

  4. #4

    Default

    Quote Originally Posted by 440roadrunner View Post
    Magnetic timing why?
    I went with magnetic timing because it was cheap & available compared to the dual sync distributor.

    Alternator why?
    The SI alternator is old technology, and GM made the CS alternator to better work with the demands of EFI.

    Where did you get this from?
    This is my own issue & post.

  5. #5

    Default

    Would the one wire alternator cause the Sniper EFI to quickly cut off & back on above 3000 RPM?

  6. #6
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    19,283

    Default

    No, that seems like a momentary loss of RPM signal.
    http://documents.holley.com/199r11369.pdf (Holley Sniper EFI Troubleshooting Guide)
    May God's grace bless you in the Lord Jesus Christ.

    '78 BRONCO: 508" stroker, TFS heads, 11:1 comp ratio, Dominator MPFI & DIS, cold air induction, Spal dual 12" fans/aluminum radiator, dual 3" exhaust/Magnaflow mufflers, Moroso vacuum pump, Accusump, engine oil & trans fluid coolers, 100HP progressive dry direct-port NOS, A/C, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, 3:1 Atlas II, modified Dana 44/60-lockers-4.10s, hydroboost/4-disc brakes, ram-assist/heim joint steering, Cage long radius arms, traction bars, 4" Skyjacker lift, 35" mud tires

  7. #7

    Default

    Quote Originally Posted by ChevyC10 View Post
    I went with magnetic timing because it was cheap & available compared to the dual sync distributor.
    The SI alternator is old technology, and GM made the CS alternator to better work with the demands of EFI.
    This is my own issue & post.
    Hi, what I'm trying to get from you is why you seem to have concluded that an SI somehow won't work? I mean, is your build "up against" the amperage firewall, or why?

  8. #8

    Default

    SI alternators do not have the EMI suppression that a CS alternator does.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us