I have an 01 2wd SCREW 5.4
Got a Hypertech 41035 and programmed to the power tune with 87 octane fuel and I made the shifts more firm, that's it.

Definately woke the motor up, but now I get Detonation, espically at free way speeds when I floor it to pass some chump in a 4cyl honda...

I've tried Shell gas, Citgo, Kangaroo, Krogers, no difference with any of them.

Plugs do have 105k on them in case that's a factor, plan on having a shop change them next week.

Any ideas? Should I move up to 89 Octane $$$

Thanks guys,

 

you said: "power tune"

is that the 87 octane tune or the 91 octane tune?????

i'd change plugs and COPs asap

*edit* try running 91 octane if you can't get 93

 

I did the 87 octane tune, should I put 89 in it to see of the detonation goes away?

What are the COP's ? coil on plugs?
If so, should I replace with factory motorcrafts or some other aftermarket brand?

Thank you!

 

try the highest octane you can get when I was running the hypertech in my 2001 I set it to the 91 octane tune and ran 93 octane and it never had a detonation problem...

yes the Coil Over Plugs

i've seen a few guys run the accels and they are a bit cheaper than stock and seem to last longer but the MSD are supposed ot be the best ones for our trucks but are pretty $$$$


are you running a stock intake? or do you have a CAI/FIPK????
what mods are done to your truck???

does the truck detonate when it's cool outside (less than 80 F) ??

*edit* when was the last time you changed your fuel filter????

 

Hi, changed fuel filter 5,000 miles ago.

It detonates when it's cool or warm out.

No other mods but a K&N filter, no cold air intake type device

I have 105k miles on it, never changed oxygen sensors, should I do that too?

Thank you!

 

definantly change the upstream sensors (the front ones)

maybe your engine has streched timing chains...

when did you install the K&N filter?

try cleaning your MAF sensor (with the spray cleaner) maybe you got some filter oil on the MAF sensor and that's messing up the readings

has your crank positioning sensor ever been messed with??

also try the higher octane fuel and see if that makes the detonation go away

 

ok, I'll change the upstream O2 sensors.

Dunno about timing chains being stretched, bought the truck with 75k on it, never had detonation before I programmed it.

I'll try higher octane fuel once I burn through this tank.

The K&N has been on the truck for 2 years, I'll clean the MAF sensor tonight.

Anyone have a good lead on low cost high quality O2 sensors?

Thanks guys, I do appreciate it.

 

any update???

I used the bosch ones that autozone sells