View Full Version : Backfire on Decel, Then Floods. 22RE

07-18-2012, 11:11 AM
So heres the problem.

Cracked my exhaust manifold where it bolts to the downpipe Before the O2 sensor. It ran great for a while just had a loud exhaust. Took it on a 950 km road trip (sorry dont know mile conversion) after about 2/3 of the trip my exhaust started backfiring, noticed a decrease in fuel economy. Kept going on in my trip it was fine. Went wheeling for 5 days, no issue except for minor backfiring while cruising down an FSR. Drive home, Truck was fine until i started going downhill, I live in the canadian rockies so these are big hills... Truck would backfire a lot downhill unless i kept my foot on the gas. If i let it backfire for to long it would flood itself out if i hit the gas and die.

My guess here is that the crack in the manifold got worse and is letting to much air in the exhaust before the O2 and my o2 is telling the ecu to dump more fuel in thus causing it to run rich and the excess fuel is thus burning in the exhaust. My question is, can i unplug my o2 sensor until i can get a new manifold or headers or will i still have said issue?

07-18-2012, 04:30 PM
found my exhaust leak culprit. I snapped a stud right where the manifold meets the head so i put some muffler cement on it for now hope it holds until headers arrive