Tvis Problem?

[TheNOBBLER[RL]]

Hi,

I have a problem with my AE82 Twin Cam rolla.

 

The car has lost almost all low down grunt. It still runs as per usual above 4400rpm, and will still rev cleanly to redline but anything below that point is just a joke. From taking off at traffic lights to overtaking, its almost dangerous

 

Has anyone had this problem before?

I was thinking that the TVIS butterflies are stuck open? Any ideas?

[lammi]

I'm a noob, but your ignition or cam timing could be out, and check all the vacuum lines going to the tvis system, one of them could be blocked.

 

my car has little bottom end power, but thats because it has bigger cams in it :hammer: could probably do with a head recondition/port polish and new rings...but thats money i don't have :lolcry:

 

just checked the 4age manual. grab urself a vacuum guage and with a 3 way connecter put it between the vsv and the actuator (see pic). the guage should show that there is vacuum under approx 4350 (when tvis kicks in) and there should be no vacuum when tvis is on.

Edited July 20, 2006 by lammi

[TheNOBBLER[RL]]

sounds like a plan, thanks.

I will check the lines once I get it on a hoist, I'm not even gonna try to get to it otherwise! What a pain of a spot!

 

Thanks again,

Jarrad

[Medicine_Man]

Or to test you could simply disconnect the vacuum line from the TVIS and block it off. The second runners in the TVIS are open until they have vacuum to close them (Controlled by the TVIS Vacuum Switching Valve). So if your VSV is disconnected/dead or has a problem then you may be experiencing similar problems to what you have described. On my 4AGE I'm just going to leave it disconnected, Matt (AKA Teddy) had his done the same and it still went like a shower of shit..

[lammi]

thatd probably be a lot easier haha. :hammer:

[Jason]

TVIS=Tgay

[lammi]

i bet you wouldnt say that if u owned a car with a bigport

[Mr Revhead[RL]]

no

if you have TVIS leave it working

disabling it WILL lose power/torque.

 

if it doesnt, then it wasnt working right in the first place

[TheNOBBLER[RL]]

Ok,

I disconected it and blocked it off, no difference, so there is a problem.

For something different i ran a vacume line from the throttle body to the tvis line which made it a pleasure to drive in traffic again!

I reconected it all the way its supposed to be thismorning and its working again. Might have been a blocked/disconnected line after all.

 

lammi, are you still running the tvis with the bigger cams? how does it go either way?

 

Thanks for your help everyone.

[lammi]

I'm gunna go test it out now, i think itll be gay coz most of my power comes from when tvis kick in but for the sake of it ill test it. will post up results in a min.

[lammi]

BLOODY HELL.....and i thought i had no bottom end power WITH tvis connected haha

[TheNOBBLER[RL]]

BLOODY HELL.....and i thought i had no bottom end power WITH tvis connected haha

 

Haha, and you probably only had to drive around the block like that! I had to drive to melb from Mildura (about 600km) like that! The only way to over take was to slap it back to third. I used 80litres of fuel on the trip to, I usually use half that.