VVT Not Enabled

[DoubleV]

Hi everyone, I recently noticed I'm probably having a similar issue...
I had the recall done to my engine and then had engine rebuild due due to a broken chain tensioner.
I replaced both timing chains, tensioners and guides. Took the opportunity to change the rod bearings to new ones and now I have a P0341 that doesn't go away.
I've cleaned the cam sprocket and checked that nothing was broken inside.
Also tested the wiring and sensors and everything looks ok.
Replaced the OCV and camshaft position sensor with new ones and the issue remains.

The engine runs ok but starts with the CEL. After it's warmed up (coolant at 90ºC) I can clear the CEL and it never comes back until the next day as soon as I start the engine when it's already cold.

I've posted some stuff I noticed yesterday about the VVT on my engine.

Can you guys help?

https://www.ft86club.com/forums/showthread.php?t=142891

Thanks!

[Smaay]

im having this same problem with my 13 FRS. It started again today, driving there is hardly any power. I have the Edelbrock SC with their tune (i know it sucks). sometimes if i stop at a red light, it corrected itself and i have my power back. today, the entire drive to work it was crap!

Of course Im never able to get a log of it happening, it always fixes itself when I hook up the laptop.

Is this an engine issue, cam gear issue, ECU issue. I tried to find a TSB or recall like mentioned but cant find it.

[x808drifter]

You have a CAT?
Clogged/busted CAT maybe.

[tomm.brz]

no worries

sometimes vvt is tricky to enable... USUALLY the only conditions are that oil must be over 30 celsius and car idling lower than 1000rpm
But if your car doesnt enable vvt that way just waiting... your engine is unlucky like mine :P i tuned other 40-50 brz and around 10% of them were the same...
no big deal


Anyway the problem shows only on the first TWO engine start ups after a reflash OR a battery removal OR dtc reset

What you can do to speed it up and activate it 100% of the times:

-do not wait too much after first start, and start driving until oil is at least 30 celsius
-when oil is warm enough, the ecu wants to see your car stopped at idle, so stop at idle in neutral and it should activate...
if not:
-drive more and be sure to overcome 3500 rpm, and go faster than 60 km/h
- try to do a lot of engine braking with gear on and no throttle
-after these conditions are met, slow down to idle and Neutral... vvt will activate 99,9%

the second start will be more problematic because vvt will start not enabled and it requires more time to calibrate and activate.. it will be mostly useless to do the same thing you have to do the first start up and vvt will keep being 0

So, do not use too much throttle because your vvt is disactivated, but you just have to drive more, speed up more and reach higher rpm and do a lot of engine braking... also cruise control low speed in sixth seems to help sometimes, but usually i get it to activate while slowly engine braking from 100km/h


From the third start up, it will ALWAYS activate every time, just briefly not when cold-starting with oil around or sub-0 celsius

I programmed a blinking CEL for when vvt is disabled so that 'd help a lot