1GR-FE Bank 1 VVTi issues P0011 P0012 & P0016

Nice. You could search "Oil control" on https://www.toyotapartsdeal.com and see what it says for your exact truck. I think you should be looking for 15340-0P010 IIRC

 

Just closing this up. The new OCV is in and you could tell immediately the difference (AKA it ran smooth as opposed to feeling like you were in a oversized popcorn popper). Codes are also gone.

To those of you that jumped in to offer suggestions... beware, you're on my contact list for the next time I screw something up!

 

This is a fantastic thread, representative of the best-quality knowledge, information sharing, & diagnostic/repair technique on TW forums.

It turns out I've joined the "pending P0012 code" club. No other drivetrain-related codes at present or in my short (8K mile / 18 month) time owning the truck.
(Just got a real scan tool this afternoon, picked up a used Autel MS906TS used on eBay for a fair price. (Previously I'd had just a $20 Amazon code reader.))

Vehicle history & my brief history of usage of it:
The patient is a 2014 AC Taco V6 MT TRD/OR w/ 70K miles w/ factory tow package, engine ID code GRN245L-CRFDKA, more or less bone stock except for ~+450 lbs of bed cap, lumber rack, & front bumper. Stock 16" wheels & all-terrain tires, no lift or re-gearing. Bought used from first owner at ~62K miles w/ good dealer service records.

Notably, the front crankshaft seal failed on the road at 42K miles, leading to "smoke and steam coming from under the hood," as reported by the driver at that time & recorded on the dealer service notes. Severe oil leakage around/under the engine. I cringe to think of it but one would surmise based on the report of smoke/steam that the engine ran low on oil at that time.

Repaired under warranty by dealer, as documented in the dealer service records. Engine has not burned any oil or any coolant since I got it and has sounded/run perfect since I got it. Very recently (250 miles ago) I performed a cold-engine compression test & got readings in the 195 PSI range except for 1 cyclinder at 185 PSI, still within spec. Performed 2 back-to-back block tests & these showed no evidence of exhuast gases in coolant. Extensive bottom- and side-view flex-neck video camera inspection reveals cylinders & heads that appear to be in pretty good / normal condition. (Some carbon build-up. Light vertical scoring in a few areas on a couple of cylinders, original cross-hatching still 98-100% present in all cyclinders.) (Still working on getting inspection videos uploaded to youtube so I can share them here for reference and/or comment.)

I run 10W-30 5W-30 Costco (Kirkland Signature) synthetic oil, OCI of 3K to 4K miles, using OEM oil filter. Fuel is plain 87-octane, 95% of the time from Costco as well. I don't use any fuel system additives. Driving patterns are typical daily-driver, 15% in town, 80% highway, 5% dirt/fire road in 4WD. I tow moderate loads only occasionally. Usually light on the gas pedal but attempt occasional "Italian tune-ups" by pushing it to 4.5-5K rpm under load up a long ~7% highway grade, maybe 20-30 second "pulls" before letting off the throttle.

Truck has been getting inconsistent mileage lately, seeming to fluctuate between 12 and 20 MPG given similar driving conditions, routes cargo, etc. Previously my average mileage was around 16-17MPG. Motor sounds good & normal under all operating conditions.

I have not yet pulled/checked the OCV filter screens or inspected the VVTi wiring harness for possible damage. My first guess is that the Bank 1 VVTi solenoid is becoming "weak" as reported by some others both on TW & other forums, i.e. either return spring is weakening or some kind of varnishing or obstruction are preventing full stroke of the valve.

Question: Are Bank 1 & Bank 2 VVTi solenoids identical part numbers & fully interchangeable, or are they separate parts? If they are separate parts can someone post the correct part # for the Bank 2 / Driver side VVTi solenoid as well?

Edit/Update: The Bank 1 & Bank 2 VVTi solenoids are definitely separate parts & not interchangeable. See my follow-up post later in this thread for details & parts diagram. (I plan to buy both to have a spare on-hand and/or preventatively-replace the Drivers side if it doesn't ohm out well or has other visible issues such as a weakening return spring.)

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A comment on someone testing their solenoid outside the vehicle using a 9V battery and getting "mostly consistent" but not 100% consistent operation: 9V might be too low and/or the 9V battery was running out of capacity & the voltage was drooping during operation. Also, solenoid may not "like" 100% duty cycle when it appears to be designed for a ~??25-30% duty cycle according to Toyota's waveform diagrams.

I have been thinking about getting a Picoscope. Passing waveform-generator duty cycles into an ordinary audio amplifier w/ the volume knob set correctly should yield very clean 12V duty-cycled square waves for testing the solenoids off-truck.

 

You have basically the same truck and miles as me (mine is a double cab at 75k), the solenoids are different and not interchangeable as the hold down is on opposite sides.
Running a heavier oil than specified could have an effect on mileage and VVT operation but it shouldn't vary that wildly.

 

I mis-reported the oil weight in original post, now edited/corrected. Just double-checked and the stock of oil I keep on-hand for the truck 5W-30, as-specified on the oil filler cap.

I will look around & try to find the part number for the Driver's/#2 solenoid.

 

Bank 1 (Passenger) aka "Right" VVTi valve for the 1GR-FE 4.0L engine, model code GRN245L-CRFDKA in my truck is: 15330-0P010
It looks like the part # for the Drivers/Bank 2, aka "Left" VVTi solenoid is probably: 15340-0P010

I've cross-checked & confirmed that this looks like the correct part for my engine variant. (Also fits many other 1GR-FE variants, but cross-check your exact variant code before ordering. The engine code is printed along w/ the VIN, GVWR, etc. on the driver's side door pillar sticker.)

Attached is a parts diagram from Toyota Parts. It's a bit confusing that the assembly part number for the Bank 1 solenoid in the diagram (i.e. both the solenoid & its O-ring) is listed as "15330B," while the Bank 2 solenoid is just a plain "15340" without any alphabetic suffix. But I don't find any "15330B-0P010" parts for sale on the web. Only "15330-0P010", which is still pictured as the complete assembly including the O-ring.

I've ordered both an original/OEM 15340-0P010 and a 15330-0P010. Current price before shipping & tax was about $80.00 each from an eBay seller w/ good reputation.

 

Parts arrived. Here are photos for general interest. The ebay seller "Toyolex Parts" has an excellent rep (100 positive%) with >56,000 items sold so I'm pretty confident these are genuine Toyota parts. I'm not familiar w/ the complete range of different genuine-Toyota packaging; I was expecting the usual red-and-white striped box. I sent this seller the make/model/engine code as well as my VIN # before the purchase & they confirmed that these are the correct parts.

 

I didn't manually clear the pending P0012 code, just let it sit & kept driving the truck. 5 or 6 more drive cycles of various kinds (short town trips, one or two 30-mile highway runs) and the code cleared itself. Must've been a transient issue possibly caused by my pushing RPMs very hard under high hill-climbing load.

Glad I didn't go pulling & replacing VVT solenoids yet. Will keep the ones I bought, might need them in future, worst case I could always re-sell them on eBay.

Might look into this with an oscilloscope on cam & crank positions sensors + VVTi solenoid current + voltage waveforms, comparing Bank 1 vs. Bank 2 traces. Does the ECU always feed identical PWM VVT solenoid drive signal to both banks? I would assume yes since the timing on both banks should always be symmetrical at any given moment?

 

The duty cycle may be slightly different bank to bank as it controls the solenoid based on desired vs actual timing and the solenoids may differ slightly on what duty cycle they open/close/hold at.
Idle Cam/Crank Captures posted here.
https://www.tacomaworld.com/threads/4-0l-scope-captures.759406/

 

This thread prompted me to take care of my occasional P0012 code today. Truck ran fine, just threw the code sometimes if I pulled some high RPMs.

Of course, what should have been a 30-minute job turned into two hours because I had the same valve/solenoid separation issue. After rereading the thread and looking at a couple of YouTube videos for the issue, I managed to thread in a M10x1.25 bolt and pry it out without much difficulty. This bolt was perfect for the job, I think it managed nearly two full turns so it had good bite. I think it was about 30mm long with an integrated washer.



I didn't have a P0012 code before I started, but upon restart it popped up. I cleared it and restarted, all's good. We'll see if it's gone for good.

This is a great thread, I expect it'll be helping folks for years to come.

 

Just a quick follow-up on this, about 10 months / 7,000 miles later, and 2 oil changes, odo at 75K miles.

The P0012 code never re-appeared after that one time so I've taken no further action.

I check the oil level religiously in the truck, it is always at the full mark, engine doesn't burn any oil or coolant. I wonder if it could have been momentary low oil pressure starving one or both of the OCVs for a few seconds due to pushing the engine pretty hard up (5Kish rpm for 20-30 seconds) on a moderate on-highway grade. (7% grade or so?)

Since the original occurrence the engine behavior, sound, mileage, etc. all seem normal. I still have the 2 brand-new OCVs on the shelf & will hold on to them just in case.

Haven't yet checked the OCV screens or done any on-vehicle ohming/amping of the OCVs.

 

how hard are those 2 screen filters to get at and replace ?

 

how hard are these screens to get at?

 

The passenger side is pretty easy. The drivers side is a bit tougher. See the parts diagram above in post 66

 

VVT-i engines require pristine oil quality.
Looking at the photo on the first page, I see a lot of sludge buildup.
This tells me "infrequent oil changes" which bring about the various VVT-i problems.

 

That picture was just for reference - showing timing marks. Its not anything related to VVTi other than timing chains.

While regular oil changes are certainly important, most of the failures in this threads are just unlucky spool valve failures

 

Been doing some research on these OCV's to try and diagnose a shudder that I have around 40 mph and doing roughly 1,100 rpm's. The original thought was that it was a bad torque converter, however I believe it is engine shudder due to these OCV's being bad (spring's inside the OCV might have gone bad). I do not have any codes/check engine lights. Anyone else have similar symptoms before they changed theirs out for the new ones? 2012 4.0L with 198,000 miles so the timeline checks out as well.

 

Id expect you would have codes being thrown if thats the case. Those symptoms could possibly be a carrier bearing going out?

 

That's what I thought too - watch this video (Tacoma P0022 Cam Code Fix and Torque Convertor Shudder Fix - YouTube) then read some comments and tell me what you think. Mostly just looking to see if anyone had the same symptoms as me before replacing both oil control valves.

 

I've seen where a few members have had various driveability concerns with no codes be caused by failing oil control valves.

About the only test you can do to eliminate them is unplug them (this will set codes), drive it, and see if the concern goes away, if it does chances are it's the valves. If it doesn't then it's more likely you have another issue.