1ZZFE (2000's Corolla) VVti troubles

[pidster]

2004 Corolla, 1zzFE 1.8, manual trans. Maintained VERY well.

Car has had a persisting "Cam timing over retarded" code, cant recall the DTC code number offhand for a couple years. No one can figure it out for us. Car runs 98% fine, hesitates on accel occasionally. CEL light comes on, stays for a while, goes off at random & comes back at random.

Any ideas?

 

[pidster]

Oh BTW dealer has replaced oil control valve, as well as ECU under warranty just before it expired, prob seemed gone couple months then came back. Dealer is basically stumped as to why it isn't fixed lol.

My mom's car, she's just kind of given up on chasing the dealer and lives with it but I just KNOW there's a fairly simple fix out there. I just don't know where to start & understand very little of how VVTi systems work.

Any input at all on the subject is welcome.

 

[bepperb]

Assuming it's the same setup at the 2az-fe, it's not a complex system but I'm not sure I'd throw a lot of money at it. There's a crank position sensor, a cam position sensor on the vvti cams, the oil valve actuator. The two sensors decide where they want to be with one another, and use the oil pressure to drive vanes in a unit on the end of the cam to change this.

When the engine is off, the vanes on the end of the cam are in full retard, and they are locked in place by a pin. When you remove the cam for inspection, you actually use air pressure to release this lock. My guess is that yours is getting stuck in a locked in full retard state.

I'm really not sure why. IIRC there is a screen before the oil control valve that could be dirty and not letting enough pressure in to unlock it. Could be junk elsewhere, or you don't have enough pressure. Or, could be a bad vane unit on the end of the cam.

Assuming you didn't jump a tooth on the timing chain, I'd be tempted to live with it.

 

[pidster]

Thanks for the input, makes sense, ya from what little I understand oil pressure is used to advance teh cams. Do you know where the pickup and screen for this system is? Is it somewhere that it could have been damaged during an oil change? My Ma says this problem started all of a sudden after a dealer oil change couple years back. I highly doubt a skipped timing chain as probs are so intermittent, and the car runs too smooth & perfect most of the time.

I can't imagine it's a dirty or sludged screen. Oil was dealer changed according to factory intervals during warranty and changed by me at 5-6k all synthetic after.

 

[ARCOgraphite]

My vvti acts up a lot - went to syn and happens less frequently - but periodically itll go/stick full advance and run like nasty at low rpm. Engine HATES 5w-20 and the thailand toyota denso - but love the OEM toyota japan denso (not stocked) runs OK on wix 51396/4 and purolator premium 0 hate bosch purolator or any high effeicincy filter - maybe my oil feed screen is plugged?

 

[ARCOgraphite]

If the dealer attempted a repair and the syptom came back soon after attempt, they still owe you the repair after warranty. Call toyota customer care.

 

[pidster]

Originally Posted By: ARCOgraphite
If the dealer attempted a repair and the syptom came back soon after attempt, they still owe you the repair after warranty. Call toyota customer care.


Absolutely they do, and if it were my car id go back 50 times if I had to. She just does not care enough about the problem to keep chasing them. I'm hoping its something I can fix at home. Bugs me more than her and I almost NEVER drive that car lol.

I just want to track down the likely cause. I pretty much rule out the oil control valve or electronics/sensors. I guess the oil passage is clogged or bent or something in the cam sprocket is stuck?

Could be coincidental but thicker/fresh oil seems to make the problem less frequent. Using GC the light stayed off for days when usually this comes & goes daily.

 

[ARCOgraphite]

its too hard as a "driveway" job- very involved - go to a corolla site - my yaris site has online repair manual free! Back to the dealer with it. BTW My 1nz hates very thin oil or almost any GF4 oil.

 

[friendly_jacek]

I would clean the OCV filter according to this writeup:
http://www.corolland.com/forums/index.php?/topic/22499-diy-info-some-uncommon-maintenance-items

I have almost 70000 miles on mine and plan to do it preventative this spring.

 

[mikered30]

Here is a TSB for the same generation as your car, but not your car year, may shed some light on your issue: TSB
Also see:
http://www.9thgencorolla.com/forum/showthread.php?p=835398

Did the dealer also replace the screen for the OCV how is the PCV valve?

http://www.newcelica.org/forums/showthread.php?t=250432
EDIT: he beat me to it!

This is always handy- 30 MB manual:
Manual