mannydantyla
New member
I bought the AIS bypass kit from Jeff, $48 shipped, and it's ready to install but I want to make sure I really need it before performing the mod in case it's not removable.
I'm not having problems with my AIS yet and I don't know exactly how common the problem is but there's 165,000 miles on the vehicle and, reportedly, that's around the age that folks start having problems with the AIS system. (FYI and as far as I understand it, the AIS system pumps air into the exhaust manifold to be "burned" in the catalytic converter to quickly warm it up. Once its a operating temp, the valve closes. The problem is that the valves, once for each header, can get jammed open or closed when the paper filter crumbles and gets sucked into the air pump. And its only for the '05+ v8 engines. Toyota issued recalls for this engine part in the Tundra, Sequoia, etc. but not the 4Runner for some reason. Again, this is just as I understand it and not to be taken as expert testimony.)
I understand the AIS system is there to extend the life the catalytic converters as well as reduce emissions during warm up, right? I would say that after 165,000 miles it did its job and can be gracefully retired before it fails and causes $1500 in repairs.
Or would I be better off maintaining the AIS system rather than bypassing it? And would would that include? Replacing the filter and oiling/greasing the moving parts?? And it is possible to install the bypass kit after it fails, but it can become a bit trickier especially if the valve is stuck in the open position.
Thanks!
I'm not having problems with my AIS yet and I don't know exactly how common the problem is but there's 165,000 miles on the vehicle and, reportedly, that's around the age that folks start having problems with the AIS system. (FYI and as far as I understand it, the AIS system pumps air into the exhaust manifold to be "burned" in the catalytic converter to quickly warm it up. Once its a operating temp, the valve closes. The problem is that the valves, once for each header, can get jammed open or closed when the paper filter crumbles and gets sucked into the air pump. And its only for the '05+ v8 engines. Toyota issued recalls for this engine part in the Tundra, Sequoia, etc. but not the 4Runner for some reason. Again, this is just as I understand it and not to be taken as expert testimony.)
I understand the AIS system is there to extend the life the catalytic converters as well as reduce emissions during warm up, right? I would say that after 165,000 miles it did its job and can be gracefully retired before it fails and causes $1500 in repairs.
Or would I be better off maintaining the AIS system rather than bypassing it? And would would that include? Replacing the filter and oiling/greasing the moving parts?? And it is possible to install the bypass kit after it fails, but it can become a bit trickier especially if the valve is stuck in the open position.
Thanks!
Last edited: