Altezza No-Start

Discussion in 'Japanese Cars' started by Meowmix, Jan 1, 2020.

  1. Meowmix

    Meowmix New Member

    Joined:
    Nov 7, 2015
    Messages:
    5
    Hey Guys,

    I have a stock 2000 JDM Toyota Altezza and I am experiencing a no-start condition.

    The car will only start/kick over if it’s been sitting for a few hours and only once. Any consecutive attempts does not work.
    I have gotten it started and held at 3000 RPM, but after about 15 seconds the engine suddenly shuts off. While it ran, everything was smooth as can be expected.

    This problem was initially noticed 6 months ago when the engine would misfire and shut off randomly, but I would still able to restart with some effort and carry on normally.
    This happened a few times within weeks and disappeared for months, until one day a few weeks ago. The engine died while on the road but I restarted with a lot of effort. It was misfiring so much that I eventually had to get it towed back home. The misfiring is noticeable with a higher engine load and will come and go regardless of cold/hot engine.


    Things I have checked:

    - Battery is new and put on a battery tender
    - No CEL
    - No blown fuses
    - Compression tested normal for all cylinders
    - Starter cranks normally

    AIR
    - MAF sensor provides a reading over OBD.
    - Unplugging MAF yields no difference
    - Vacuum tested normal
    - ethrottle body responsive and tracking input
    x Catalytic converter not yet inspected for blockage

    EFI
    - Fuel pump newly replaced as repair attempt
    - Fuel pump audibly works during start attempts
    x Injectors not checked but unlikely

    IGN
    - Spark plugs slightly fouled, coated with fuel maybe from all my start attempts.
    - Spark plugs appear to fire, but only once per cylinder per attempt
    - Ignition coil replaced 6 months ago, no sign of excessive wear

    I am running out of tricks and am now wondering if there is an issue with the crank/cam angle sensors, or them being out of sync.
    I have manually turned the engine to TDC and the cam gear/crank pully indicators line up with their respective markers, so I don’t think there’s a physical alignment issue.
    I have probed all three sensors with an AC voltmeter while hand cranking the engine and I do get a noticeable response from them when the engine turns.

    Please let me know what you think.

    Thanks guys.
     
  2. RyanV

    RyanV Member

    Joined:
    Jun 20, 2013
    Messages:
    1,883
    Location:
    Langley, BC
    I haven't had an Altezza, but I had similar issues over the last while with my wife's E46 330i. It had a no start issue that would happen randomly, but only when warm. Sometimes it would start again after 30 minutes, but sometimes it would be hours. Changing the crank position sensor cured this issue.

    Next it was just a misfire, but this turned out to be just a coil pack. All coil packs tested out ok by resistance, but when checked at the shop with an oscilloscope (or whatever they used) it showed that one pack was bad. I confirmed this by just switching out the one pack and have since bought all new coil packs since they were all original.

    Latest issue is long crank and it happens only when warm. Without going into more detail, based on what I saw with the E46, I know you mentioned the coil packs are new, but maybe getting them checked and looking at the crank and cam position sensors like you mentioned would be a good start.
     
  3. Meowmix

    Meowmix New Member

    Joined:
    Nov 7, 2015
    Messages:
    5
    I measured all three cam and crank position sensors. These are two wire inductive type. Without the luxury of an oscilloscope to test with, I measured their resistance.
    All three had infinite resistance with the engine off. I took one of the sensors off the car and waved a magnet at it, and read 3.5VACmax. And only if I wave at it will I get around 500 Ohms max (which is still not to spec).

    Bit of a coincidence if this means all three sensors are dead.
     
  4. tperkins

    tperkins Devout AYC Disciple

    Joined:
    Jul 3, 2013
    Messages:
    716
    Location:
    Slave Lake
    All 3 sensors dead seems pretty suspicious.

    Maybe this is 4G63 influence but I probably would have started with replacing the cam position sensor.

    While you are probing the sensors, try tapping them with your finger and see if any of them are doing funny things.