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Discussion Starter #1
Ok need help I have a 2018 l5p just did the full delete and started it up tonight. My fuel gauge isnt working it shows empty and I have a check engine light on that has a u18a2 code and truck stays in high idle until I put it in drive
 

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This prolly isnt what you want to hear on a Friday night, but your best bet is to contact the company that did your tuning & get them to straighten out since it sounds like a software issue with the electronic fuel gauge not working and the high idle.
 

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Check connections. If no remedy, call tuner
 

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Discussion Starter #4
Ya sucks I have to wait I'm disconnecting the negatives for 10 minutes and see what that does if nothing then I have to see what they say. Also remote start doesn't work
 

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I think, as a rule, remote start won't work with a CEL on. Could be wrong... especially if you don't have any lol
 

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Discussion Starter #8
Yes the remote start issue is correct I forgot. Update I think I may have solved the issue well I have to wait till monday for the part to ship and so I can call and verify it's the issue. However I never installed the can bus harness when I removed the def tank. So hopefully when that comes in itll fix it
 

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Just curious, did the CAN BUS plug resolve your issue?
 

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Dude hasnt logged back in in 5 months. Would have been nice to hear the results for anyone else possibly dealing with similar issues.
 

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For anyone curious, the canbus plugs have to be installed, or your fuel gauge won’t work, as well as some other issues. Lift pump pressure will max out to 95 psi. Removing sensors, and not installing the plugs interrupts communications. You can either install the plugs, or leave the factory sensors plugged in, as they complete the circuit as well.


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The "plugs" - are those dead sensors? Kinda like what we used to do with O2s on cats when using long tubes?
 

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They are just blank plugs with the canbus wires looped.

This is for a 2020, but you get the idea. You need three for the NOX sensors, and one for the DEF module.




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Man! Deleting a new truck voiding the warranty and resale!
 

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I had this exact issue two weeks ago and was able to figure it out. Really wish more people would post their fixes once they get to them to help others.

In my case, it was the DEF maid harness can bus jumper. Whoever wire it built it upside down. De-pinned and moved everything how it should be. I used a picture of the jumper I found online to confirm how it should look and verified it with the pins on the truck side harness.


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for all that deleted your L5p do you have smoke out of exhaust?
 

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Not really. Few puffs here and there when you really lay it on the pedal. Given, still need to install the downpipe


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