I have major power loss that occurs randomly with no codes. stock or tuned. At first I thought it was bad fuel but I have ruled that out. One thing I have noticed when this happens my timing is way in the negatives, but the knock sensor is also in the negatives. Boost is normal the whole time. Once over about 3k its fine and timing looks normal. WOT is normal as wel but you don't spend much time under 3k if any. Then maybe the next time I drive it it won't happen at all. It can be so bad at times that the truck has to downshift just to get up a hill cruising where it normally would not. Any thoughts on what this could be? Truck has 40k miles. Plugs are maybe 30k old. Truck has been running on unleashed 89 tune with no less than 91 octane. However going back to stock the issue is still there.
is there anything else I could look at in a data log that may shed some light or anything else to check?
is there anything else I could look at in a data log that may shed some light or anything else to check?