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Thread: can i put off adrdressing ltft until next week and still drive?

  1. #1
    Tuner in Training
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    can i put off adrdressing ltft until next week and still drive?

    high fuel trim after summit drive.hpl
    Got tuned yesterday and left with no laptop connected.
    This morning I drove an hour and back to summit and the van performed flawlessly
    later in the day i decided i should log some data since i didnt on the trip to summit. and I
    noticed the high ltft (my tuner did bring this up yesterday)

    it couldve done this the entire time i was driving today and just didnt know about it i suppose?

    im thinking ill try and swap the o2 in the morning, even though the unit is a nearly new denso unit.
    any other ideas?

    intake gasket is new too, new oe injectors as well.

    looking for thoughts on me driving this an hour each day this coming week until next weekend

  2. #2
    Advanced Tuner
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    I suspect a completely dead cylinder on bank 2. Bank 1 is good, and bank 2 is averaging around 20% lean. Unless you have a massive intake leak that somehow only supplies air to bank 2, you have a dead misfire.

  3. #3
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    Quote Originally Posted by gametech View Post
    I suspect a completely dead cylinder on bank 2. Bank 1 is good, and bank 2 is averaging around 20% lean. Unless you have a massive intake leak that somehow only supplies air to bank 2, you have a dead misfire.

    How do I start fixing this? Plugs?

  4. #4
    Advanced Tuner
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    Quote Originally Posted by FASTRO VAN View Post
    How do I start fixing this? Plugs?
    Plugs should tell you which one is not firing. The cause will have to be determined then, but could be as simple as a wire not snapped all the way on, so make sure to note any difference in feel when you remove the wires. Definitely fix it soon, as the excess fuel being dumped into the other cylinders will foul plugs and wash rings over time, as well as clogging cat converters if you have them.

  5. #5
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    Quote Originally Posted by gametech View Post
    Plugs should tell you which one is not firing. The cause will have to be determined then, but could be as simple as a wire not snapped all the way on, so make sure to note any difference in feel when you remove the wires. Definitely fix it soon, as the excess fuel being dumped into the other cylinders will foul plugs and wash rings over time, as well as clogging cat converters if you have them.
    Thank you for your guidance! I?m pulling plugs tomorrow and won?t be driving it again until issue is resolved!

  6. #6
    Senior Tuner
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    Check for exhaust leaks before or after the sensor. Check o2 sensor heater fuses. It might also be just a failing sensor. It isn't a tuning issue.

    You have knock sensor codes pending.
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  7. #7
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    Quote Originally Posted by Alvin View Post
    Check for exhaust leaks before or after the sensor. Check o2 sensor heater fuses. It might also be just a failing sensor. It isn't a tuning issue.

    You have knock sensor codes pending.
    Alvin you are the man. It was in the exhaust shop about a week ago to have the exhaust made. Both O2s are new Denso units and the knock sensors are new Dorman units that came with a new harness. It seems like the O2s were communicating, but I know nothing, could one still be faulty? Should my first move be take it back to the exhaust shop and ask them to check for any leaks they may have left? Or do I swap O2s from side to side to see if the condition follows?

    Pulling plugs out of a 6.0 sucks when it?s crammed into a van. But I suppose I?ll almost certainly need to because the fuel has likely fouled them huh?