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6-spd w. 35" tires: engine valve knocking sound issue

beaups

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https://carcomputerexchange.com/blog/how-car-computers-work/
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What’s more is that these engine computers are also self-learning devices that have been programmed to adjust for driving conditions and the habits of the driver. This means that the computer will make small adjustments to different parts of the engine and different systems in order to adapt to varying environmental conditions and to the way you, specifically, drive your car.
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And based on my motorcycle tuning experience, if new cars are anything like the new bike computers, they are self-learning so will modify their own "permanent" curve gradually over time and your fuel injection curve at 2000 miles will not look the same as when your car is gonna be at 50000 miles. Albeit there is a preset limit for variation, call it a "limiter" if you will so that the curve never gets too out of wack. some bikes was 15-20% max variation from stock for example and you can't get a good tune for a heavily modified engine unless you unlock the computer to bypass that threshold. So go to back to my statement, I was just stating it wasn't good to use oversize tires without compensating for it, especially when the vehicule is new. OP just confirmed by fixing his values in the computer that it now operates within those "limiter" parameters and it wasn't before.
Not a single word of that is true, including your quote from that article.
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BlackGenesis

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So, @mwilk012 , @Oldbear , @Karnak, @SargeRubicon14. Just an update. I finally caved in and got the Flashcal JL and set my tire size to 34.25 (my actual size). The valve noise is all gone! It seems like no matter what transmission type is there, the computer regulates the fuel intake and whatever else and the tire size setting DO matter. I test drove on the lowest gear as I possibly could and the engine runs perfectly. Not that I plan to be lugging the engine, but now I can drive in peace and hear no noisy valves. I'm a happy camper now.
With manual transmission, engine only looking at rpm, load, temp. Putting larger heavier tires is no different then towing a trailer. If anything you might be more aware about your driving habits.

When it comes to ECU learning: car runs dictated air to fuel ratio in closed loop, adjusts fuel accordingly to achieve that ratio of 14.7, any omidiat fuel adjustment to get the car to 14.7 stored in sort trim fuel table and if fuel adjustment is needed for prolong time (numerous seconds) its stored in long fuel trim.

Myself, I dont understant how one would expect to accelerate in a jeep at below 2k rpms. 2k is cruising rpm and downshift to accelerate ideally 2.5k or higher.
 
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intentsrig

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I am a manual transmission as well and I still get the pinging, especially when it is hot out. 91 octane helps but does not cure it 100%.
 
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coolcj7

coolcj7

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Myself, I dont understant how one would expect to accelerate in a jeep at below 2k rpms. 2k is cruising rpm and downshift to accelerate ideally 2.5k or higher.
Because, especially in a heavy street traffic, you wouldn't drive on the 1st gear but on the 2nd one at least and this is where your RPMs drop. Maybe you would use 1st gear, I don't know, I don't do that. For me 1st gear is only for taking off and not for slow drive over longer period.
 

GeoTracker

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Have you had a chance to pull codes to see if you have a misfire?
 

Dethwalkin

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Does it sound like this? If your answer is yes then it's your lifters and rockers.
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