back-firing

Discussion in 'Hot Air (non-intercooled) Tech' started by derrick, Apr 28, 2012.

  1. derrick Member

    Message Count:
    97
    Online
    hi

    couple of weeks ago i was doing some work on my car 85 grand national replaced some engine parts and a tune up after i finished everything. told the car for a drive and at low rpm the car back-fires thru the exhaust not load but i can hear it when driving. i did pull the egr stuff out. could i have i injectors wiring mixed up the did pull the top half of the motor off.
  2. Jerryl Doing MORE with LESS!

    Message Count:
    5,900
    Offline
    What scantool do you have?
  3. derrick Member

    Message Count:
    97
    Online
    dont have one
  4. Jerryl Doing MORE with LESS!

    Message Count:
    5,900
    Offline
    I am going to get slammed for this but . . . . truth is truth.

    A scan tool is not really needed, “IF” you have great knowledge of these cars, and GREAT diagnostic and analytical skills.
    For most of us (99%), that is not the case and a scan tool on these cars is vital and saves a LOT of time!
    They are a LOT cheaper than head gasket replacement and engine rebuilding costs.

    If the car is running OK otherwise and you are at stock boost levels (8-10), I would not worry too much.

    If you run a stock car at stock boost levels, probably can get away with not having one.
    If you try to push it like most of us, you are going to need a scan tool, period.

    If you had a recording scan tool we could get you some accurate opinions.
    From the sound of it I would guess;
    Weak Ignition system
    Bad plugs /wires
    Bad O2 sensor
    Voltage / Ground issues
  5. grnadnasty84 Spell-check Please!

    Message Count:
    128
    Offline
    I had this same problem for a long time and couldn't figure it out. I replaced the maf with a stock unit and it didn't fix it. I then replaced the maf with the ls1 maf and translator and the problem was gone. Don't know if that'll fix yours but that's what worked for me. Good luck
  6. derrick Member

    Message Count:
    97
    Online
    for the most part is it stock except for exhaust. it has brand new plugs,plugs wires and o2 sensor.

Share This Page

^ Top