Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 35

Thread: Engine cranks but no start today

  1. #11
    Moderator Eggman's Avatar
    Join Date
    Sep 2015
    Location
    Cleveland, Ohio
    Country
    United States
    Posts
    10,163
    Thanks
    4,039
    Thanked 2,788 Times in 2,107 Posts
    Quote Originally Posted by Space Wolf View Post
    He told me that this is normal for any modern car, and what caused this. I'll try to repeat it in English. It's due to the hydrolic valves. They need oil pressure to open the valves.
    While it's true hydraulic valves need oil pressure to operate, that is not what was causing your problem. The 3A92 engine in the Mirage does not have hydraulic valves - it uses solid tappets for lifters.

    Your engine was simply flooded with excess fuel. Holding your accelerator pedal to the floor helped clear the flood condition.


        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 manual: 49.6 mpg (US) ... 21.1 km/L ... 4.7 L/100 km ... 59.5 mpg (Imp)


  2. #12
    Senior Member
    Join Date
    Dec 2017
    Location
    the Netherlands
    Country
    Netherlands
    Posts
    340
    Thanks
    16
    Thanked 158 Times in 109 Posts
    Quote Originally Posted by Eggman View Post
    While it's true hydraulic valves need oil pressure to operate, that is not what was causing your problem. The 3A92 engine in the Mirage does not have hydraulic valves - it uses solid tappets for lifters.

    Your engine was simply flooded with excess fuel. Holding your accelerator pedal to the floor helped clear the flood condition.
    Really? Does it matter that my car has an 1L 3A90 engine?

        __________________________________________

        click to view fuel log View my fuel log 2013 Space Star Cleartec Intense 1.0 manual: 55.7 mpg (US) ... 23.7 km/L ... 4.2 L/100 km ... 66.9 mpg (Imp)


  3. #13
    Moderator Eggman's Avatar
    Join Date
    Sep 2015
    Location
    Cleveland, Ohio
    Country
    United States
    Posts
    10,163
    Thanks
    4,039
    Thanked 2,788 Times in 2,107 Posts
    Quote Originally Posted by Space Wolf View Post
    Really? Does it matter that my car has an 1L 3A90 engine?
    Good point. Do you think Mitsubishi used a different valvetrain design for the 3A90?

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 manual: 49.6 mpg (US) ... 21.1 km/L ... 4.7 L/100 km ... 59.5 mpg (Imp)


  4. #14
    Senior Member
    Join Date
    Dec 2017
    Location
    the Netherlands
    Country
    Netherlands
    Posts
    340
    Thanks
    16
    Thanked 158 Times in 109 Posts
    I'm not very literate in car engines, but I think a different valvetrain would change the engine that much that it wouldn't be considered another incarnation of the same engine, like the 1.0L and 1.2L are. But I'm not sure, so I asked.

        __________________________________________

        click to view fuel log View my fuel log 2013 Space Star Cleartec Intense 1.0 manual: 55.7 mpg (US) ... 23.7 km/L ... 4.2 L/100 km ... 66.9 mpg (Imp)


  5. #15
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    Don't believe everything a tow truck driver tells you. They have practical experience, as in "this happens a lot, and here's how you can fix it", but they're really guessing as to the cause of the problem in a lot of cases.

    As has been stated, it's a simple matter of flooding the engine with too much fuel. And if you're not careful, it's easy to make a flooded engine MORE flooded. And a significant flood IS hard to clear.

    There's a lot going on between the ECU and fuel injectors when you cold-start a car. There's a "priming pulse" to ensure that the fuel injectors are fully primed so that you get accurate fueling. And then there's "cranking fuel", which is about 3x what you normally need to run the engine just to get it to fire up. After the engine is running, there's "after start enrichment", which will taper off over a few seconds as the engine stabilizes. And THEN you get into "warm-up enrichment", which essentially does the same thing tapering off until the engine reaches operating temperature.

    Shutting the car off immediately after starting when it's in the "after start enrichment", or just at the beginning of "warm-up enrichment", there's a LOT of fuel in the cylinders. Then adding another priming pulse and a bunch of "cranking fuel"... that's what's causing a lot of these no-start conditions.

    If you have several failed starting attempts back-to-back, you're probably introducing a priming pulse with each attempt (it may have a timer to prevent that), and you're spewing lots of cranking fuel each time.

    The solution is to put your foot to the floor while cranking. This tells the ECU you're trying to clear a flood, and it stops spraying fuel. Then you crank the engine, pumping fresh air through the engine, carrying some of that fuel with it on every cycle, until the mixture reaches a point where it can light off.

    It's all very simple stuff, you just need to wrap your head around what's happening.
    Simplify and add lightness.

  6. The Following User Says Thank You to Loren For This Useful Post:

    Fummins (08-28-2018)

  7. #16
    Yes people who work for places like ama or other roadside assistance company's aren't always the most mechanically inclined. They're handy when you're in a bind but anyone with a drivers licence can work for them. There are some pretty well trained guys who are awesome at their job but I've seen more than one that sucks at what they do.
    Mirage videos:

        __________________________________________

        click to view fuel log View my fuel log 2014 Mirage SE wussie cvt edition. 1.2 automatic: 37.7 mpg (US) ... 16.0 km/L ... 6.2 L/100 km ... 45.3 mpg (Imp)


  8. #17
    Senior Member Top_Fuel's Avatar
    Join Date
    Feb 2016
    Location
    Ohio
    Country
    United States
    Posts
    3,699
    Thanks
    2,582
    Thanked 2,537 Times in 1,471 Posts
    Quote Originally Posted by Fummins View Post
    There are some pretty well trained guys who are awesome at their job but I've seen more than one that sucks at what they do.
    So they're just like the Service Managers at my dealer?!?

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 manual: 52.2 mpg (US) ... 22.2 km/L ... 4.5 L/100 km ... 62.6 mpg (Imp)


  9. #18
    Your not alone there!
    Mirage videos:

        __________________________________________

        click to view fuel log View my fuel log 2014 Mirage SE wussie cvt edition. 1.2 automatic: 37.7 mpg (US) ... 16.0 km/L ... 6.2 L/100 km ... 45.3 mpg (Imp)


  10. #19
    Senior Member
    Join Date
    Dec 2017
    Location
    the Netherlands
    Country
    Netherlands
    Posts
    340
    Thanks
    16
    Thanked 158 Times in 109 Posts
    Quote Originally Posted by Loren View Post
    Don't believe everything a tow truck driver tells you.
    I can't let that go. An ANWB Wegenwacht (Royal Dutch Touring Club Roadside Assistant) is not a tow truck driver. Actually they don't tow at all. (Unless your car broke down on a very dangerous spot, in that case they'll tow it to a safer place). They are qualified car mechanics, and their goal is to repair a car at the place it broke down. In most cases they succeed, and if not, a local tow truck driver is called.

        __________________________________________

        click to view fuel log View my fuel log 2013 Space Star Cleartec Intense 1.0 manual: 55.7 mpg (US) ... 23.7 km/L ... 4.2 L/100 km ... 66.9 mpg (Imp)


  11. #20
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    Fair enough. In this case, though... his logic was wrong.

    I've owned cars with hydraulic lifters. They start just fine with "flat" lifters. They just make a lot of racket until they get pumped up. And they're very sensitive to not just oil pressure, but the weight of the oil. Typical old Miata, you know it's time for an oil change when your valves start ticking more than usual!


    Simplify and add lightness.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •