Welcome to Club Hot Rod!  The premier site for everything to do with Hot Rod, Customs, Low Riders, Rat Rods, and more. 

  •  » Members from all over the US and the world!
  •  » Help from all over the world for your questions
  •  » Build logs for you and all members
  •  » Blogs
  •  » Image Gallery
  •  » Many thousands of members and hundreds of thousands of posts! 

YES! I want to register an account for free right now!  p.s.: For registered members this ad will NOT show

 

Thread: Pulsing/Surging Idle
          
   
   

Reply To Thread
Results 1 to 4 of 4
  1. #1
    yodasands is offline CHR Member Visit my Photo Gallery
    Join Date
    Mar 2005
    Location
    Phoenix
    Posts
    9

    Pulsing/Surging Idle

     



    Hello again gentlemen. My father and I have finally got the Jeep running with the 350 chevy transplant.

    I have a question though.

    In the last few days it has developed a problem. While parked in idle the engine will surge and fade sometimes stalling out. It can run very rough after startup. The other day while driving it the idle slowly crept up to about 2500 RPMs causing the engine to overheat. Sometimes it will run fine with no problems. We hooked it up the the computer and it was throwing a code 44 lean (O2 sensor). We replaced the O2 sensor with no change. Fuel delivery seems to be fine. TPS is new. IAC is new. Injectors are new.

    Does anyone else have any suggestions as to what could be causing this?

    Thanks,
    Dan

  2. #2
    firebird45331 is offline CHR Member Visit my Photo Gallery
    Join Date
    Mar 2005
    Location
    Greenville
    Car Year, Make, Model: 86 firebird
    Posts
    371

    any vaccum leaks along the intake?

  3. #3
    Gullwings's Avatar
    Gullwings is offline CHR Member Visit my Photo Gallery
    Join Date
    Oct 2004
    Location
    Huntington Beach
    Car Year, Make, Model: 1960 Chevy Impala & 1994 Camaro Z28
    Posts
    7

    What generation 350 are you running. If it's one of the early Lt1's with the Optispark that could also cause a surging problem.
    My 94 Z28 had a similar problem and it was the Opti.
    Other Posibilities vacuum leak as mentioned above or the a sticking EGR valve if so equiped.
    Gullwings (Max)
    1960 Impala sport coupe
    94 Camaro Z28 LT1, A4, 3.23
    Eibach Pro-Kit Springs, KYB-AGX Shocks, Moroso CAI, TrickFlow Intake elbow, Flowmaster exhaust

  4. #4
    yodasands is offline CHR Member Visit my Photo Gallery
    Join Date
    Mar 2005
    Location
    Phoenix
    Posts
    9

    It WAS the EGR valve. On further inspection we realized that we had not replaced it with a new one. Once replaced the loping is gone.

    It seems that the idle is a little high now (100 rpms or so). Should we readjust the base timing now with the new EGR valve?

    Everything else seems to be running well.

    Thanks again for all of your help.

    Dan

Reply To 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
Links monetized by VigLink