87 4.3 TBI stalls occiansionally

Discussion in 'Performance & Fuel' started by johna20376, Nov 26, 2011.

  1. johna20376

    johna20376 New Member

    I have a 87 el Camino 4.3. TBI. Once in a while after pulling off interstate it will run rough and die. It will start right back up but have to keep throttle pushed to clear out fuel then it runs fine. The other time it will do the same thing is if I punch the throttle and come to a stop and run rough and die etc. Could this be a fuel regulator? Fuel pump is new. Other than this it runs perfect.
    Thanks for any help.
    John
     
  2. Ethan

    Ethan Rockstar 100 Posts

    Sure it's a 87? I think 88 is the first year they started TBI. If it's a faulty fuel pressure regulator, you usually get extended starts, and running rich. It can be one or both of two things, ignition coil is weak, or the IAC valve is getting stuck closed.

    I'm leaning towards it being the ignition coil, since when you suddenly flood the engine with fuel, it can't burn it off, and dies due to weak spark.
     
  3. mudpuppy

    mudpuppy Rockstar 100 Posts

    theres a possibility it could be weak injectors. after going into the cycle rate for the loadX the injectors might not be closing properly allowing for excess full to dump in. can you copy the fault with it on jack stands? if so watch the injectors at the tb and see if they are still pumping in fuel after to release the throttle. since there is no a/f wide band data log system much like what the obd2 systems have the pc is useless if tracking weather its burning rich or not. you might be able to tell signs from the spark plugs. if they are old enough you will also be able to tell if its the ignition failing or to much fuel.

    another possibility but likely not the problem would be a faulty cat/cats. if they are clogged up it could run fine under normal condition but cause to much back pressure choking the engine at higher rpm.
     

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