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S110P takes 3 tries to start when cold

Discussion in 'Daihatsu Hi jet' started by MrJPolito, Jan 13, 2022.

  1. MrJPolito

    MrJPolito Member

    My automatic Hijet S110P truck (EF-ES fuel injection engine) takes three tries to start before it idles smoothly. I crank the key, it struggles to start, idles VERY rough, then stalls out. After the third (sometimes fourth) time cranking the key, it idles fine.

    I only noticed that this was happening when it was cold outside. When the engine is warm this does not happen; cranks and starts perfectly fine after I drive it to the store and start it again in the parking lot or whatever.

    Recently cleaned out my throttle body and ISC (idle speed control) valve. They weren't very dirty, but I figured this is the most obvious place to look when you're trying to figure out rough idle issues.

    Before cleaning (it wasn't even very dirty):

    photo_2022-01-12_23-25-33.jpg photo_2022-01-12_23-23-29.jpg

    I followed these instructions to test my ISC valve by hooking up the terminals to a 9v battery: https://www.toyotanation.com/thread...on-the-toyota-idle-air-control-valve.1676205/

    Pictures of how to test the ISC valve from the article:


    The valve opens and closes as described. However, it is about half-open when there is no battery power applied to either terminal. Is this normal? (picture below)


    If this is normal, I don't know what else to check to try and fix this issue.

    I did recently replace the fuel filter with one that is supposed to fit a Toyota 4runner, so it's a bit different in shape and wasn't unidirectional like the old filter, and I also recently cleaned fuel injectors and replaced O-rings, and installed a new distributor rotor and cap and spark plugs. But I didn't notice any issues with those back when I installed them, and it was still summer so it wasn't cold enough to cause these problems.

    Any ideas?
  2. MrJPolito

    MrJPolito Member

    Here is a comparison between the new fuel filter I installed (left) and the old fuel filter (right), if that matters:
  3. Roadster

    Roadster Active Member

    You might try one of those cheap plastic see-thru filters mounted on a 45* up towards the engine... I had some issue with filters developing an air lock and not filling with fuel. Mine is not FI so might not be a problem on yours...
  4. DEG95DH

    DEG95DH Member

    Mine does the same, but doesn't sound as severe as yours. We had some 40 degree days a few weeks back, and it would take 1-2 times. Usually, it would start, sound like it was definitely about to die...and then come to life and work fine. So, I don't think it was a cold or warm engine issue, but a fuel pressure issue. I.e., you could drive it to the store, park it for a few hours until it is cold, but then it would still start fine? Is that accurate?

    I figured it was the pressure regulator somehow leaking pressure over time. Once the line re-filled and pressured up, then it idled great. But, I would expect this to happen any time the vehicle sits for a few days...or whatever amount of time would be needed to significantly depressure back to the tank?

    Seems our fuel pumps are in the tank. Not sure if they run when the key is on, or if they only run when rpms are sensed (I think the EFI ECU has an rpm input, so I could see both ways). On a small engine with relatively short fuel lines, I would not be surprised if the pump doesn't start until you start engaging the starter.
  5. MrJPolito

    MrJPolito Member

    I think if I leave it long enough until the engine becomes cold it doesn't start right away.

    The more I think about it the more I believe it's fuel related. Pumping the acceleration pedal does nothing. So the butterfly valve is open all the way and it's getting tons of air but there's no acceleration, which means there's not enough fuel burning.

    When I turn the key I don't hear anything pumping, so the fuel pump is probably only turning on when the engine runs. On my Honda Acty you can hear the fuel pump running when the key is just turned on to the accessory position, and that never had issues starting.

    I'm betting there's a loss in fuel pressure as the car sits.
  6. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    The fuel pump should run with the key in the run position. Even if the engine isn’t running. Try stopping at “on” for a ten count before going to start.
    DEG95DH likes this.
  7. DEG95DH

    DEG95DH Member

    I agree. I just got back to my truck today. It’s been sitting for 5 days. About 50 degF outside. I turned the key to ON and heard fuel pump run for about 2 seconds. Didn’t start it, but turned key back off and then back on. 2 seconds. I did this about 5 times. 2 seconds every time. AFTER all that, I started and it did fine.

    So I propose a variation to Jigs suggestion. Don’t turn it on and count to 10. Instead, turn it on, count to 2, do this 5 times!! :D Then try starting and see if any better.
  8. Arty

    Arty Active Member

    I'm going to try the "key to on, then wait ten seconds" routine on my '92 MiniCab.
    It too stumbles and dies a few times when the weather gets to -15C and colder.
  9. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    It might help, but is kind of dependent on whether you have an electric fuel pump. It did help when I installed the electric pump on my Hijet. I can turn it on and wait until the pump starts cutting out as the system comes up to pressure, and then pump the pedal four or five, (eight when it is below zero).

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