1jz vvti running issue

Thread in 'Technical Questions' started by Zammish24, Feb 25, 2020.

  1. Zammish24

    Zammish24 Member

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    Need help guys, ive had this issue since day one. I've changed, coils, plugs, vvti solenoid, cam sensor, temp sensor, cleaned maf, timing marks all line up.. oh and I've bought another stock ecu and still have this issue.

    Whats happening is when im cruising, i can feel the car push-pull like something's knocking back the timing or a very soft misfire if i hold the revs higher than idle.
    Its a 1jz vvti from a jzx100, only mods are intake, exhaust and coil on plugs

    Sometimes when i floor it it feels like the engine doesn't wake up till about 4000rpm where its a sudden burst of power
    Feels like a soft misfire... did some diagnosis on the car, unplugged the injectors all the contacts were clean and dry and had no damage on the plugs.
    Checked the voltages to the fuel pump had a solid 14v no no problems there.
    Pulled off the top cover to check the coils, i cant see any problem there (but i have ordered a new set anyway since they're cheap)
    Unplugged the IACV to see if that changes anything and made no difference.
    Cleaned the maf sensor and its made no difference.
    Oil level is fine and levels are fine
    I will get a timing light on it next but you guys think of anything else where i can look?
    Im also running NGK bkr7e plugs gapped to 0.6
     
  2. Spawn_CA18

    Spawn_CA18 Member

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    2 things came to my mind. Have you done J-pipe delete and did you grounded the head(I'm assuming its a swapped engine)?
     
  3. Zammish24

    Zammish24 Member

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    No engines completely stock and there is a ground wire going from head to bulkhead
     
  4. LUX1

    LUX1 Member

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    checked for boost leaks? can be tiny and might cause some of your said issues
     
  5. Zammish24

    Zammish24 Member

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    Heres a vid so u can see what its doing
     
  6. ukdelsol

    ukdelsol Member

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    What condition were the coilpack clips in and are the wires in the right way? I know they are prone to falling apart.
     
  7. ukdelsol

    ukdelsol Member

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    Can anyone check there coilpack wires on each coilpack and verify which way they are by chance ..... got a feeling one of mine may be wrong .
     

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