Once again......... DETONATION

[bluesvt]

Alright, I have filled up at many different places and changed the fuel filter twice now. The other day while it was warmer I changed the tune to warm and still got it. I can only hear it at about 45-50 mph under half throttle in 4th gear. It is very quiet but still it is happening, what can be done??? I thought possibly it was a vacuum hose on the elbow that popped off but its zip tied on there now and still doing it. :hammer:

[Silver_2000]

warm tune will detonate in this weather
even if everything else is right

[bluesvt]

warm tune will detonate in this weather
even if everything else is right

It was about 60 outside a few weeks back.

[Silver_2000]

It was about 60 outside a few weeks back.

if my truck was detonating on a cold tune the last thing i would do is try a warm tune. I would sooner pull the chip. For around here 60 is not warm

In many/most cases the warm tune runs MORE timing - which is a primary cause of detonation

I would get some professional help from Terry before it gets any worse
perhaps buy 30 bucks worth of 104 octane to see if it makes a difference

[L8 APEX]

If I tuned the truck I can back it down for you. I have received some calls lately about detonation from tunes that ran for years without issues. I am leaning towards the 10% ethanol gasoline being part of this new trend. For any of my customers experiencing tip in detonation I will be more than happy to adjust your tune for the new conditions/fuels we are operating under.

[Mark #2]

I am leaning towards the 10% ethanol gasoline being part of this new trend

I agree, the K5 has had slight detonation recently accelerating the real truck(SO's terminology, L is a toy) on to the highway, never did it before in 20 years.:confused:

[my2002lightning]

I have even noticed a "difference" in my stock-L performance recently. This is with TX. 93 Mobil/Shell fuel.

I may take it to OK. this weekend for 91+ and see what she does for comparison.

Ronald

[Beaudee]

I'd deff. take it to Terry.Maybe try some fuel injector cleaner.I havent noticed any diff @ all with the way mine runs.I do run injector cleaner every once in a while,and perfer chevron gas.I need to get my plugs changed soon and i plan on seeing Terry to eyeball em and check my tunes.Good luck with it.Put some long tube headers on it,i had to take some fuel out when mine got installed.Youll love the sound to.

[Silver_2000]

I know that mine has seen a loss in MPG with the ethanol gas

[WA 2 FST]

I know that mine has seen a loss in MPG with the ethanol gas

Yep, mine has too.

And my TT Vette has had some slight detonation ... time for a retune on it. I definitely attribute this to the 10% E-gas.

[bluesvt]

Thank you Terry, I think that fixed it. I played with it on the way home at about 45 giving it as much throttle as I could before it shifts and got nothing. Thanks again. :tu:

[bluesvt]

What is the Data Setup?

[L8 APEX]

I updated the firmware to the new 1.15 and it has on device data logging, DTC definitions etc...

[tiffo60]

mines been detonating too but with only 11 degrees of timing i dont see how:hammer: