There was not a recall on this year Avalon for sludge. Do you have pulled specific code number that they pulled from the system to verify that the VVT I was not functioning properly? Has the valve cover been off to inspect? The front one is easy to remove to inspect for sludge. If you have This vehicle well-maintained and get your oil changed regularly sludge will not be an issue even with his high mileage.
I read the article that you linked to above it is basically the same old story that has been going on and on and on. Now Toyota is agreeing to approving some of the claims that were previously denied as far as a warranty repair but to my knowledge there is no service campaign or recall so to speak. Toyota appears to be extending the warranty which will be helpful for some consumers. I can tell you that I have worked on some of these engines that have had in excess of 200,000 miles with no visible signs of sludge and the engine ran perfectly. There is one the VVTI actuator per cylinder head. There also is one OCV or oil control valve per cylinder head to control the actuator that is attached to the end of the camshafts. I can give you more detail if you know the code number. As far as getting any kind of assistance from Toyota it never hurts to ask but given the information and the mileage on your vehicle is not likely that you would get anywhere with it but then again if you don't ask you will not know. There are many things that can cause these actuators to stick, slugging is just one of many things there could be wear in the actuator or there could be one of the OCV sticking. When the actuator sticks in the retarded or advanced position it will cause the engine to run rough.
Yes that would be fine. Gather the code numbers reply back to this post tomorrow evening I will get back to you.
Sounds like a plan. I will speak with you tomorrow you could reply then when you have the information.
The VVT system constantly adjusts intake valve timing based upon operating conditions. The ECM system controls the Oil Control Valve (OCV) with a variable duty cycle. The Oil Control Valve then supplies oil to the advance or retard side of the VVT Controller. The oil applied to the VVT Controller will cause the intake cam to advance or retard depending on the position of the Oil Control Valve. The ECM verifies that the desired camshaft angle has been achieved by monitoring the camshaft position sensor. If anything has happened to the camshaft position sensor or if a timing belt has been on this car recently there could be issues with the wiring going to the sensor or the timing belt. If these factors can be ruled out then you're probably looking at the VVT controller sticking or binding not returning back on a retarded or advanced signal. This would explain the rough idle or misfire situation.
All of this being said. You have to assume that the dealership got a timing belt on correctly mainly because the misfire and the check engine light was on previously to the timing belt being placed. It is not likely a computer problem they rarely go bad the weakest link is the OCV or oil control valve solenoid there are screens that could be plugged up. The actuators are built into the camshaft and are very expensive to replace. I would have the OCV solenoids cleaned and tested and pull the screens from the cylinder heads to have them cleaned and checked. If the actuators are not advancing or retarding as designed by the computer it is not going to hurt anything although you will lack performance and possibly compression if the cams stay at the full max retarded or advanced position. If money is tight my suggestion would be to disconnect the OCV solenoids electrical connectors when the engine is idling at its best so that the actuators cannot be advanced or retarded. This basically will set the engine back to the old style engine where the cams have to stay positioned where the actuators are. The Check engine light will remain on. Provided The cams are not retarding or advancing you shouldn't have any issues with performance.
You're welcome. If you need anything in the future just as for me, skyvisions, in the question and I will get back to you.
I hope everything works out for you. It is always best to draw on help of others.