I've got a 01 Lightning that has seems to need more octane than is normal. It's 100% stock with the exception of a stock replacement K&N filter. I live right down at sea level so always run 94 octane Chevron fuel, but even so, on cool dry days... say 35 to 40 degrees F, it'll rattle pretty good at WOT. I've never been able to run 91 or 92 octane under any conditions without hearing detonation, unless I'm inland and at an altitude above 1500ft. It actually runs very well and has turned 13.53 @ 104 with stock rubber and according to the factory gauge it makes slightly over 10lbs of boost. Has anyone else had to deal with a similar situation? Thanks

 

How long has it been since you changed the fuel filter?

 

detonating with stock tune and boost is NOT common

Make SURE your computer REALLY is stock

 

Indeed. 104 trap speed sounds a little high for a stock truck.

 

I know the truck is totally stock since I've owned it since new. The only mod is the replacement K&N filter. It has been at least 2 years since it's seen a filter so maybe I'll start there. I was thinking of going to a colder thermostat and adding water wetter to both the rad and intercooler thinking that might help. It's got me quite baffled as it seems to detonate worse when the air is cool and as all of you know, normally detonation is more of a hot air temp problem. It's due for some new plugs too so I was thinking of maybe going to some IT22's for a little extra insurance. I'm kinda shooting in the dark here.... just don't want to blow it up......

 

you wana change that fule filter ever oil change.! the IT22's are great you can use those or NGK TR-6's...im runing them now. Dotn wate 2 years to clean or replace a filter thats pushing it if you drive ever day.. I would say start with the fule filter and plugs and go from their..!good luck.

 

2 Years YIKES (change that filter, it could be your whole prob)

It will always detonate more in the cold weather, when you have cooler denser air you have more boost more power and up to 3 degrees more timing.

How many miles on the truck ???
An oil soaked intercooler, clogged cats, bad 02 sensor, inj, fuel pump, relay, intercooler pump, can all cause what you describe also....

GOOD LUCK

 

Change Out 02 Sensors, Front 2, And Clean And Or Replace Your Maf.

 

Fuel filter is a great place to start. Next, make sure your intercooler pump is circulating coolant. Cooler plugs are a good idea, but should not be necessary at stock boost levels. Check for unmetered air getting into the intake. A lean mixture is sure to detonate at high load, or low temp conditions.
Jim

 

I'm with Rob, how many miles on the truck?