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2001 Warning Light And no Reverse!

Discussion in 'Gen 2 Prius Technical Discussion' started by nuclear_j, Jan 2, 2009.

  1. Patrick Wong

    Patrick Wong DIY Enthusiast

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    In post #9 you indicated that your car logged DTC P0301, so this implies a current misfire in cyl. 1. However in post #20 you said that you replaced the spark plugs six months ago. This prompts a few questions:

    - What replacement plugs did you use?

    - Did you remove the plugs and look at them today or in the very recent past (since starting this message string)? If not, this should be done.

    Also, look for water that may accumulate in the spark plug wells. Water may drip down from the cowl onto the valve cover. The rubber gasket between the igniter and the valve cover may allow some water to seep into the spark plug well.

    If you see any water, this would likely cause a misfire. Use compressed air to blow out the water before removing the spark plugs.

    When you remove the spark igniters, you should clean the dirt off the top of each one (I use paint thinner as a solvent, moistening a paper towel and then wiping off the dirt. Do not get the igniter very wet, make sure it is completely dry before reinstalling.) After the dirt is gone, carefully inspect the igniter body, looking for cracking or burn marks. Look at the high voltage connector at the bottom, and the low voltage connector at the top. If you see any corrosion, this would be another reason to replace the igniter.
     
  2. nuclear_j

    nuclear_j New Member

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    Well I replaced the spark plugs six months ago and again a few days ago per your advice. I used NGK Iridium BKR5EIX-11 spark plugs. And when I replaced them a few days ago they looked normal to me.

    Are the igniters the plastic clamps that attached to that rubber thing you put on top of the spark plug?
     
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The repair manual indicates NGK IFR5A11, but I suppose that BKR5EIX-11 will work. I understand that you have new plugs installed now. Are the plugs torqued to 13 ft.-lb?

    Yes, the igniters are more than just a plastic clamp. That plastic body contains a little ignition coil that increases the low voltage pulse applied to the coil, up to the voltage required to fire the spark plug (probably 25-30K volts). If your plugs are new, there's no water in the spark plug wells, and you still have a misfire, then the problem is either the spark igniter or the fuel injector.

    Did you try clearing the codes; if so did they return? If they returned and you want to continue DIY, then you'll need to read the DTC. I suggest that you spend around $150 - $200 to get a decent OBD-II code reader so that you can see what are the current DTC that the engine ECU is producing.

    I also suggest that you make sure that the wire harness connectors to the spark igniters and the fuel injectors are all secure and in good condition.

    If you still have P0301, then the first thing I suggest is moving the igniter from cyl 1 to cyl 4, and vice-versa, then clear the DTC. See if the problem moves to cyl 4 which would give you P0304. If yes, then you can feel confident that replacing the igniter will solve the problem.

    If the problem stays with cyl 1, then the next thing I would suggest is to swap fuel injectors. If you haven't done this in the past, you will need to access the repair manual info at techinfo.toyota.com

    This will be a big job because you have to remove the valve cover so that the fuel rail can be lifted up. You also have to relieve pressure on the fuel line before you play around with the injectors. One way is to start the engine in inspection mode, let it run, then remove the circuit opening relay to cut power to the fuel pump. Let the engine run until it dies. Then the fuel line pressure should be relieved.
     
  4. wyounger

    wyounger New Member

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    Does this car have a good 12 volt battery? Are we sure?

    Alllll sorts of weird things happen in modern cars when they have a marginal battery. Priuses are just odd in that they don't use 12 volts to actually start the engine- so it might start anyway- but a weak 12 volt system can certainly confuse the computers to no end, and that can make them set all kinds of trouble codes that aren't really true.
     
  5. nuclear_j

    nuclear_j New Member

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