Image Please bare with us while we are carrying out some much needed maintenance to the forum. New look coming soon!

What triggers the VVti?

Post info/questions on engine mods and issues here
dogger
Noob!
Posts: 18
Joined: Tue Oct 01, 2013 9:01 pm

What triggers the VVti?

Postby dogger » Wed Jan 20, 2016 7:53 am

Hi, im fitting a blacktop beams into my ae86.
i was wondering what conditions the ecu needs to see, to trigger the VVti?
im sure with vtec it needs water temp, oil pressure, revs and >10mph.
i dont have a plug on the speed sensor on my gearbox, so will i not be able to hit the VVti?

turbotezza
Trc Off
Posts: 65
Joined: Fri Dec 06, 2013 8:48 am

Re: What triggers the VVti?

Postby turbotezza » Wed Mar 16, 2016 6:41 pm

search google matey i remeber reading about it somewhat pls post what you find

Protok
Tezza Fanatic!
Posts: 372
Joined: Sun Aug 15, 2010 8:56 pm

Re: What triggers the VVti?

Postby Protok » Wed Mar 16, 2016 10:03 pm

VVTi isn't triggered, it is constantly on adjusting timing as needed.

User avatar
RS Tom-Hundred
Tezza Fanatic!
Posts: 450
Joined: Fri Nov 28, 2014 3:31 pm
Location: Cambridgeshire

Re: What triggers the VVti?

Postby RS Tom-Hundred » Fri Mar 18, 2016 9:22 am

As Protok says, it is constantly advancing and retarding timing to set it to the optimum level for either economy or performance. This is on both exhaust and intake cam pulleys in the case of the black top 3SGE and it uses the solenoids on the top of the engine to feed oil into chambers in the pulleys to turn then internally and advance/retard them.

turbotezza
Trc Off
Posts: 65
Joined: Fri Dec 06, 2013 8:48 am

Re: What triggers the VVti?

Postby turbotezza » Mon Mar 21, 2016 5:39 am

soin therory can all the oil drain out of pulleys if dismantled so the vvti movement can be done by hand??? if you read my post next to this one all comes clear why i ask

turbotezza
Trc Off
Posts: 65
Joined: Fri Dec 06, 2013 8:48 am

Re: What triggers the VVti?

Postby turbotezza » Mon Mar 21, 2016 5:41 am

when i say dismantled i mean pulleys taken off cams not pulleys taken apart as i know dont ever do that1

User avatar
Tosh21
Altezza Guru
Posts: 521
Joined: Mon Jan 20, 2014 10:12 pm
Location: Oxfordshire

Re: What triggers the VVti?

Postby Tosh21 » Sat Mar 26, 2016 9:24 am

Yes you can move them by hand (apparently, I've never tried it) but Yea I read somewhere that they constantly move and adjust timing. I'm pretty sure it uses water temp and I assume it's the usual stuff like rpm speed maybe maf for engine load too.

Out of curiosity, Why does it even have a speed sensor on the box I thought that was inky for auto cars

turbotezza
Trc Off
Posts: 65
Joined: Fri Dec 06, 2013 8:48 am

Re: What triggers the VVti?

Postby turbotezza » Mon Mar 28, 2016 9:23 am

have no idea ,,road speed ?

User avatar
RS Tom-Hundred
Tezza Fanatic!
Posts: 450
Joined: Fri Nov 28, 2014 3:31 pm
Location: Cambridgeshire

Re: What triggers the VVti?

Postby RS Tom-Hundred » Tue Apr 05, 2016 9:01 am

When I had my engine apart last year to diagnose a knock, I also found that the cams have a little "free play" of maybe 10 degrees or so when putting a spanner on by hand. One moves more freely in both directions than the other. I think I uploaded a video on here actually to ask if it was ok. Reason I checked was I thought maybe the VVTi was faulty but turned out to be a big end bearing gone.

User avatar
RS Tom-Hundred
Tezza Fanatic!
Posts: 450
Joined: Fri Nov 28, 2014 3:31 pm
Location: Cambridgeshire

Re: What triggers the VVti?

Postby RS Tom-Hundred » Tue Apr 05, 2016 9:04 am

CORRECTION!

On mine the exhaust side didnt move but the intake side did. I just looked on my Youtube and found the video I did.

Here it is, hope this helps
http://www.youtube.com/watch?v=6RmvZYWTkGY


Return to “Engine & Transmission section”

Who is online

Users browsing this forum: No registered users and 1 guest