Hey guys, need some help with a well overdue problem of mine. Truck is a 2000 Silverado 5.3 lm7 132k miles, headers, intake, egr delete, and tune from Xp racing okc. When I first got the truck in 2013 it had no problem with these sensors, one day they showed up so I replaced them and they came back at first drive. I then unplugged the pigtail and plugged it back in, also reset the codes and they stayed gone for a year. Well I then started adding all of the above mentioned mods over that year and the spring of 2015 they came back, most likely because of some water that had gotten under the manifold. I replaced the sensors for the second time (acdelco sensors, pigtail, and gaskets) the codes came right back and will not go away. Two weeks ago I took the truck to a reputable local repair shop to have the sensors changed for a third time and to have the harness went through. The codes are still coming right back and all ohm readings are perfect, no chaffed wires or anything of that sort. The codes I'm getting are knock sensor low input bank 1, and bank 2, no other codes besides these. I am left with no idea as what to do about this situation, except that it could possibly be the computer which I don't really want to replace but I will if it comes down to it. Please any help would be greatly appreciated so I can have a good running truck again!

 

Check the power source into their harness. Maybe the problem goes back further than was replaced.

 

I had a similar problem. I got a bad tank of 93 oct. Run that tank out and fill her up at a different gas station.

 

I know this is the least fun thing to do in the world but sounds like it is time to chase wires in the engine bay and look for abrasion.

 

i had the exact problem on my daily driver, replaced sensors 2 times and they would come back on my first or second drive, turned out it my tune, i did some small modifications someone recommended for a daily driver and that seemed to be the problem, re flashed it to stock and they never cam back on

 

I was wondering if it could be that. I really don't want to lose my tune, back when I still used the Diablosport I had no problems then. Also all wires have been checked for chaffing and many tanks of gas have been ran through it over this time frame. I'm afraid the problem lies in the tuning or the computer has a fault.

 

who did your tunning? do u have hptuners or efi live?
if u have i could go back and check what i changed for it to go away, doesnt mean u have to go stock, im pretty sure its only a small change u have to make

 

I go to Brett at XP Racing here in Oklahoma city. He uses HP tuners. I'm not really too fond of his tuning anyways, believe it or not my truck ran better on the Diablosport can tune than his dynotune. Also where can I find a new ECU for my truck? I believe that may be the cause of the problem.

 

If u want to change the ECU u can find them on ebay or junkyards, u would just need to have them reflashed with your vin number so it would work correcly with your truck, or have your tuner change the tune files

 

Get the tune gone through first, before you replace the ecm!!