Last week I decided to pull out my old Diablo chip and try it out. I filled up with 93 Octane and ran it for a day on that before installing the chip. I then pulled the battery cable for about 4 hours and installed it.

A couple days later, I took a 4 hour trip with my ATV in the back (about 1000 pounds). There was a very strong headwind so mileage sucked bad.

I noticed when I was around 2400 to 2600 rpm's, I had a real bad rattle, most likely valve clatter, in the engine. Today on my way to work, I did not notice any clatter at all.

The truck is a 2002 with a little over 190k on it. I do have the towing package. Do I need to be concerned with this? Should I pull the chip and go back to 87?

Thanks.

 

I would pull it.