OP
OP
Matthew Jeschke
Full Access Member
I used powder drain cleaner specifically Sodium Hydroxide.
Removed upper 02 sensors, put a hose in them... and plugged the flange to muffler.
Filled it with solution... Let it set for a good hour. Tapped on exhaust a few times during that time.
Then I drained it out. Started truck up w/ muffler flange disconnected. Carbon shot EVERYWHERE. I drove it about 2 miles with muffler disconnected to get that out of there... Then put everything back together and drove the truck for about an hour. Part of that VERY hard driving to heat the cats up.
Afterwards EGT at outlet of cats was 120% of inlet as expected. Prior it was same or cooler.
Removed upper 02 sensors, put a hose in them... and plugged the flange to muffler.
Filled it with solution... Let it set for a good hour. Tapped on exhaust a few times during that time.
Then I drained it out. Started truck up w/ muffler flange disconnected. Carbon shot EVERYWHERE. I drove it about 2 miles with muffler disconnected to get that out of there... Then put everything back together and drove the truck for about an hour. Part of that VERY hard driving to heat the cats up.
Afterwards EGT at outlet of cats was 120% of inlet as expected. Prior it was same or cooler.
