Browse over 9,000 car reviews

    guides

    adventureguide

    evguide

    familyguide

    tradieguide

    urbanguide

    0 Logout

    Browse over 9,000 car reviews

    My 2018 Mitsubishi Triton engine has a blow-by from the oil filler cap

    Mitsubishi Mitsubishi Advice Mitsubishi Triton Mitsubishi Triton Advice Mitsubishi Triton 2018
    ...

    I have found my 2018 Mitsubishi Triton engine has significant blow-by from the oil filler cap. Could you explain what could be causing this issue?

    Answered by CarsGuide
    14 January 2025
    David Morley

    Blow-by is a normal part of engine operation, particularly turbocharged engines where the combustion chamber pressures can be extremely high, forcing gasses past the piston rings and into the crankcase. Excess blow-by, however, suggests that there’s perhaps an overboost problem, wear in the engine or that the ventilation system designed into the emissions controls of the engine is not working properly.

    The crankcase ventilation valve would be a good place to start checking as these can become very dirty and even clogged over time in a diesel engine, and a compression test of the engine might tell you more as well. The first thing to do is find another vehicle of the exact same make and model and see if it, too, has a similar level of blow-by in evidence. From there, you can decide which way to go, but either way, a good diesel mechanic should be able to identify the problem accurately.

    Disclaimer: You acknowledge and agree that all answers are provided as a general guide only and should not be relied upon as bespoke advice. Carsguide is not liable for the accuracy of any information provided in the answers.
    Other Mitsubishi Triton Problems
    SELL ALL MITSUBISHI TRITON PROBLEMS
    Related cars for sale on CarsGuide
    See more Mitsubishi Tritons for sale

    Comments

    Have a new question for the CarsGuide team?
    More than 9,000 questions asked and answered.
    Ask now
    Complete guide to Mitsubishi Triton 2018
    Complete guide to Mitsubishi Triton 2018 CarsGuide Logo
    Reviews, price, specs and more