Hi from Australia,
Happy Friday. I have an interesting issue with my 2014 ISF and to save you all having to read a very long story I’ll highlight the dot points

Aug 2023
I did the Valley plate, timing chain, tensioner and timing gears all replaced
After this was done the engine oil was flushed twice, reassembly was done as per Toyota manual (torque specs. Etc)

Traveled only 3,000 kms since then

Today was overtaking a car in traffic went from 4th gear to 3rd and gave it half throttle.

Engine light, VSC came on car went into limp mode (Manual mode only takes off in 2nd gear and power loss)

Stopped at a servo disconnected the neg terminal of the battery for exactly 15 mins (timed it)

Plugged it back in and within 30 seconds of idling same lights popped up.

With a basic hand held OBD scanner code P0020 – I’ve done extensive googling what this could be.
(code indicates that the bank 2 intake camshaft isn't synchronized with the oil control valve because of an open or faulty circuit.)

Pulled the Camshaft solenoid out (drivers side) ohms tested it and 12V bench test both bank 1 and bank 2 operate within spec

Inspected the VVTI module no issues there (no bearing noise or resistance)

Swapped all the cam sensors from bank 1 to bank 2 and vice versa

With the engine running unplugged and scanned for codes and cleared them as I went along (this was to eliminate each individual sensor)

Inspected the plugs and wiring no damage

After spending 8 Hrs I’m out of ideas lol need a drink or two this has bam boozed me
Any ideas are highly appreciated

Addition notes:
Engine oil is changed every 5,000kms (3,106.85 Miles)

Taken from Google:
P0020 Lexus Camshaft Position A Actuator Circuit Bank 2

Possible causes
– Dirty Oil
– Faulty variable valve timing (VVT)
– Variable Valve Timing (VVT) circuit is open or shorted
– Oil Control Valve (OCV) circuit is open or shorted
– Faulty oil control valve (OCV)
– Damaged Engine Control Module (ECM)
Tech description
If the engine oil is clean and the VVT and OCV circuits are OK, replaced the VVT to resolve the problem.
What about the obd code?
After the ECM sends the target duty cycle signal to the OCV, the ECM monitors the OCV current to establish an actual duty cycle. The ECM determines the existence of a malfunction and sets the DTC when the actual duty cycle ratio varies from the target duty cycle ratio.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Lack/Loss of power
– Engine rough idle
P0020 Lexus Description
The Engine Control Module (ECM) controls the Oil Control Valve (OCV) to regulate the intake camshaft angle. As a result of the angle change, the engine timing is advance or retard. Optimizing engine timing will help the engine improve torque and fuel economy, and the exhaust emissions decrease under overall driving conditions. The Variable Valve Timing (VVT) system includes the Oil Control Valve (OCV) and VVT controller. The ECM detects the actual intake valve timing using signals from the camshaft and crankshaft position sensors, and performs feedback control.

 

Looking at this manual, it appears the ecu is complaining about the camshaft timing gear assembly that the cam phaser sit in.

https://charm.li/Lexus/2012/IS%20F%2...0Charts/P0020/

When reinstalling the cam phaser's, the camshaft timing gear assemblies need to be rotated counterclockwise until they stop

https://charm.li/Lexus/2012/IS%20F%2.../Installation/

you can see this at about 7:50 in lobuxracer's phaser replacement video

 

There is a oil screen filter in the valve cover that might be clogged. These are pics of the filter, housing, and seal in the valve cover.





There are also two o-ring seals between the valve cover and the head that might have failed. From the same thread:


Seals in place.


Seals removed.

 

Did u ever get this figured out? Have an 08 w/ 216k miles and got it a couple of days ago. Ohm tested the OCV and it was reading 8.9 so out of spec. Changed that with an aftermarket since it was cheaper than buying OEM just to try and see if the code would go away but no success. Or do i need to drive it and possibly the code will go away?

Took the cam motor out since i was there and it spun freely to me.
this member said his motor spun freely also but was able to fix the CEL with replacing the motor.
https://www.clublexus.com/forums/ls-...ing-motor.html

Also, my cam was already fully retarded when i took the cam motor out. Is that weird? I was able to freely spin it clockwise just to make sure it just wasn't stuck.

just want assurance if you happened to change the motor, as the motor is hella expensive?

TIA

 

It's not odd at all for the cam to be in the right position to install the phaser.

 

So i am only getting 1.18v from the connector to the OCV. This is most likely the issue right?

Found your posting of the ECU pinout lobux. It seems i need to check e5-19 and e5-29?

 

No. The source is the cam phaser motor. P0020 in TIS is pretty clear. On a US model, this would be the passenger side motor. On a RHD, this would be on the driver's side. Bank 2 is on the left if you are facing the engine from the front.

Ignore the solenoid. It's not causing this DTC.



Check the connectors. The bodies degrade with heat. I've replaced all of mine. Otherwise, replace the motor. The control is on the small connector (same body as the MAF), power is on the connector with two big wires.

 

What do you mean exactly by check the connectors? Just the physical part, or testing ohms and voltage?

Since i wasn't getting the more common p0012 or p0022 that definitely pointed to the cam motor, and since u posted the other things to check, i didn't want to spend the money to get the part since it is an expensive part. But i will hunker down and order the motor.

 

Troubleshooting step in TIS for this are short and sweet. Check wiring, replace motor. The wire checking is just the connector body to be sure it hasn't cracked or allowed pin to pin contact. It's very unlikely, but it's relatively easy and inexpensive to check, plus you'll be removing the connectors from the old unit when you put in the new one anyway.

 

UPDATE: bought a used part for $100 just to make sure as I didn't want to spend the big bucks if it happened to not be the issue. No offense to lobux or 93msb, but like i said, my spindle was spinning freely and wasn't the common P0022 that everyone else's car was throwing that pointed directly to the cam motor. And then you threw out some other possibilities, where i didn't want to have to remove the engine cover to check. No more CEL. I am ordering part from impex japan. Other forums vouch for this site, so taking a chance as the part is only about $500 after shipping, compared to the ridiculous US prices of about $1k for my 2008 part. I tried Amayama, but they couldn't source the part, but they were charging about $650+ for the part, but that was before i found out about impex. Thanks for everyone's input in helping me troubleshoot this.

So i guess P0020 is the code thrown for the cam motor if there is something internally wrong with it, and the P0022 is when the actual spindle doesn't spin freely mechanically.

UPDATE 2: Just got my parts from Impex today 8/8/24. So if you have patience, it really is worth it ordering through them. Supposedly it only took 3 days from Japan to get delivered here. It takes time for them to source the parts. Everything seems genuine. Just got done installing the new part.