B18c fuel cut at WOT at high rpm

Discussion in 'Honda B-Series' started by imran_akn, Monday 24th Jun, 2019.

  1. imran_akn Club Veteran ★ ★ ★ ★ ★

    Hey guys, after a long while playing with bmws im back in a proper car.. a b18c EG

    But i have problems

    The problem is.. at wide open throttle.. as it goes higher up in RPM is bogs hard. I did diagnose a little and had a gauge at the rail which shows the fuel is cutting at high RPM. If i apply gentle throtle it goes up happily.
    So far i have changed the fuel pump to no joy. Fuel filters new but i feel as though the problem may be power or electric related. Wondering if anyone has had anything like this happen?

    I will test power at the pump soon to see if its cutting but if anyone has any other suggested it would be appreciated. I have also heard mention of a fuel pump relay.. isit something i should swap out? Cars been sat for a while but the lines and tank seem clean.

    Thanks again
  2. imran_akn Club Veteran ★ ★ ★ ★ ★

    Hey guys, jus thought id update incase anyone can chime in and help. It seems the cars in limp mode. It doesnt want to read ECU codes on factory or htune ECU. Does anyone have any suggestions? I tested the TPS sensor but it seems to be giving correct figures. Iv redone the grounds. Cleaned the IACV. Unblocked the fuel lines. Any help is greatly appreciated..
    Im thinking to buy a new ignitor module (in the dizzy)
    Maybe a new TPS map and lambda. But i don't really wana throw money away blindly but i can't get a code from the car. If anyone can make logic of the situation any suggestions are appreciated.

    Cheers all
  3. MattBeardless Service Team H-Tune Staff

    United Kingdom Matt Derby
    Are you sure it's not got a vac leak?
  4. imran_akn Club Veteran ★ ★ ★ ★ ★

    iv sprayed them all down with brake cleaner and ther seems to be no leaks,

    the EML light now just stays on constant when i put the pin in, thats on my htune ECU and p30 virgin ECU

    could anyone tell me if there are any other crucial ground i should check, i have done the thermostat ground, the valve cover ground and the gearbox ground
    im a bit lost for ideas at the moment so if anyone has any direction fire away
    iv replaced the TPS sensor and tested for correct voltages
    iv tested map sensor and voltage at the plug
    the dizzy has been replaced for a known working one
    help lol
  5. markcivic1981 Club Veteran ★ ★ ★ ★ ★

    Could it be a faulty injector not supplying enough fuel at higher demand ?
  6. MattBeardless Service Team H-Tune Staff

    United Kingdom Matt Derby
    Will the code now read as the light's constant?
  7. imran_akn Club Veteran ★ ★ ★ ★ ★

    Hey guys still no code..
    Although i think i may have found something today.. you can tell me better

    So i ripped out the engine loom to do continuity tests.. all clear however i noticed the oil pressure sensor was not connected.. probably cos the oil pressure sensor has been blocked on the back of the block. Can anyone clarify the importance of this sensor. Can it put my ECU into limp mode or isit purely for an oil light. Iv ordered one regardless but just wanted some clarity. Thanks again

    Attached Files:

  8. Jason14 Valued Contributor ★ ★ ★ ☆ ☆

    I had the shame problem few years back on my EG it went into limp mode the lamba sensor was faulty I replace it along with fuel line injectors a few vac lines was agood after oh don't forget as well my injectors ..

    it could be fuel pressure thou if you fully open on the body and it bogs down seems like not enough supply of fuel. are you running a fuel pressure gauge ??
    MattBeardless likes this.