Hi all. I have a 2005 4runner. The other day I was driving on the highway and noticed that I could not accelerate above 70 mph. At 70mph, the rpm would rev up but no additional speed. I took her to the dealer who said the engine code had something to do with the secondary air intake valves sticking open. They tested it by driving the truck for 80 miles but could not replicate. Now my spouse is driving it an I would go over 2000rpms. Any ideas.
Lose of power at 2000 rpm
- Thread starter RunninPR
- Start date
Register to hide this ad
Acidmeld
New member
The valves are intermittantly sticking open. When the valve is open it allows air into the exhaust just before the air/fuel ratio sensor. The sensor then reads this extra air as a lean condition. Since the ecm is reading lean it adds fuel to richen the mixture. But since there really is no lean condition the engine ends up with a rich condition due to the excess fuel. With the mixture wrong the engine has less power than it normally would.
The only real way to fix the problem is to replace the sticking valve. Unfortunately not cheap.
The only real way to fix the problem is to replace the sticking valve. Unfortunately not cheap.
Last edited:
