I have Toyota Sienna 2001 LE
. It ran great for 6 years without any trouble. Around last month, it was not going over 30 Miles and even rpm was not going over 2000 regardless how much gas I apply. One of the mechanic ran the OBD II scanner and got Knock Sensor codes.Mechanic replaced both of them and than starts the weird problems. Mechanic showed me that Sienna start vibrating and misfiring at Idle with no braking ability and exhaust pipe start getting Cherry Red. Upon his advise I changed 2 catalytic converter ; one with 3 flanges and small middle one. The exhaust cherry red problem persists. I was not satisfied with the mechanic any more and took my car to home to get second idea.
After some research...you tubing..Sienna chat site and Haynes manual etc...
1)I replaced all Spark plugs..
2)Replaced Ignition coil all six...front and rear..
3)Took throttle body out.. scratched and cleaned with approved throttle body spray...replaced Throttle body gasket
4)Replace the IAC complete unit (140$).
5)Replaced vaccum hoses (I found few cracked vaccum hose).
6)Opened and clean Upper Intake manifold with gasket
7)Replaced the PCV valve and it's hose
8)Clean the Intake Air Control valve located at upper intake manifold.
9)Cleaned the lower intake manifold..but did not replaced the gasket
9)Replaced the cracked VSV Switch located at fuel rail
10)Replaced the MAF sensor.
After doing all of the hard work myself. I started the car ..worrying what will happen
......Luckily, the car started fine and no engine vibration and misfiring...:0..One noticeable difference was that the car idled at 2200 rmp for few minutes.I kept it running for 5 minutes .. and did Ignition off and on for 4 to 5 times. By doing that, idle is moved down to 1300 rpm at park and neutral gear. When I switch gear to Drive/Reverse ..Idle lower down even to 900rpm. I test drive the sienna for short distance and it runs fine except higher 1200 to 1300 rpm at Idle and slight sound from exhaust like leak in pipe etc.
Does any one know, how can I lower the idle little bit more by Idle screw located at throttle body? If so, where does the idle screw located at throttle body?