3VZFE Playing Up

[Gleshlich]

As some of you may know, I have recently bought a 3VZ SW20.

Wanting a bit of help of a couple problems

1. The ACIS appears to be permanently closed. There is no torque down low at all until 5k RPM where there is a huge torque shove.
2. The cold start fast idle has stopped working after I took the car into the car wash yesterday.

Anyone able to give tips or help? Located Chch

[GDII]

The ACIS is controlled by throttle position and RPM in the ECU. Physically it is controlled by a vacuum switching valve, a vacuum hose and a vacuum diaphragm. If any one of those is broken or not connected the ACIS won't work as it is meant to.

It's hard to see it working when the car has no load on the engine due to the parameters set in the ECU. The ACIS should be open at low RPM ie idle to produce a longer runner length and close at higher RPM to create a shorter runner.

I've never looked at the ACIS valve and actuator on my 3SGE to see what happens when the engine is started, I think it is supposed to be open when the car starts and closes when the ECU senses the right conditions. When the car is off, the 3SGE has the ACIS butterflies open like this.


I guess the vacuum created by the high RPM will allow it to shut when the VSV is activated.

As for cold idle, 3 wires control that. Or the valve is dirty and just decided to stop working properly.
I had this problem and it fixed it properly. Valve is to the left, coolant passed through the section on the right.

[Benckj]

Is ACIS the same as a IACV?

[Gleshlich]

Just heard back from the previous owner.

The butterflies were removed when the head porting and polishing was done along with the rebuild. He was planning on fitting a supercharger but ran out of money before the repo company came along.

I'll try some carb cleaner in the intake and see if it fixes things. Bit too cold to take parts off in Christchurch right now

[GDII]

Is ACIS the same as a IACV?

Nope, completely different. IACV is Idle Air Control Valve as you know and ACIS is Acoustic Control Intake System. It uses butterflies in the 3SGE or a single butterfly in the 3VZ to adjust in acoustics of the intake affectively increasing or decreasing the intake lengths dependant on RPM. 2 unrelated systems.

EDIT: This link explains the system and the difference between T-VIS. http://turbomr2.com/MR2/Reference/TVIS/TVIS.htm

[GDII]

Just heard back from the previous owner.

The butterflies were removed when the head porting and polishing was done along with the rebuild. He was planning on fitting a supercharger but ran out of money before the repo company came along.

I'll try some carb cleaner in the intake and see if it fixes things. Bit too cold to take parts off in Christchurch right now

That explains why it isn't working, no butterfly, no ACIS.

Best to take off the throttle body and remove the idle valve to clean it. You'll struggle to get it properly clean with just carb clean being sprayed into the intake pipe.

[Benckj]

Got it. Really need to pull IACV to clean and adust. They can be a common problem due to moisture and soot build up internally. Best to clean on bench and test - set up TPS

[Gleshlich]

Haven't had any luck with the cold start. Snapped a shift cable so ideally need to fix that first

I'm trying to get another intake manifold with a butterfly so I can ACIS. Its kind of ruined the motor without it

[Gleshlich]

Climate control has started only working on Auto or high. Is this a resistor or something?

All the vacuum plumbing on my car is in the wrong place. Will try get it to match the Camry I got

[GDII]

What do you mean by Auto and High? Does the switch only operate the fan when turned to Auto and High and not low or medium?

[Gleshlich]

What do you mean by Auto and High? Does the switch only operate the fan when turned to Auto and High and not low or medium?

Correct. I feel like I should get this shifted to the Rides section. Should I make a new thread or get an admin to do it? The cold start decided to start working again out of the blue. Weird.

Waiting on weather to get better so I can strip parts out of the Camry and fix all the vac hoses.

[Benckj]

.... I feel like I should get this shifted to the Rides section. Should I make a new thread or get an admin to do it?....

It's not really a Rides topic as you started by asking for help with the engine playing up. Probably best to leave this thread here and start another thread to report on the project as a whole. Can always provide a link to this thread for reference.