4A-FE Engine (misc.) Components questions

[JohnelP]

Hi, I tried to find the answers in the Haynes book, but it I could not find them.

Sorry if a similar topic is already started, but I could not find it with "search".

I am trying to find out what is the purpose of the ACV (air control valve) that is located on the left side of the intake manifold. ACV is the term from haynes book. I do not believe it is the IACV. It is on the OTHER side throttle body. I would expect the IACV to be around the throttle body, not on the other side. It has some wiring and little hoses connected to it. One hoselet is joining a sensor (What is that??? also??) that is exactly near wipers motor. It is between the MAP sensor and the wipers motor.
What is it and what's its usage for thar tht sensor connected to ACV?

2nd quest. On the rear side of the intake manifold, it is something that lookes like a EGR valve but does not have all the components haynes books describe for the EGR system. It has a screw and a spring, and it is bolted exacly at the middle of the intake manifold. What is that?

Can somebody give me some links with 4a-FE engine picture until I will make my pictures?

Thanks!!!!

[Flashmn]

do you have AC? I have a solenoid valve next to the wiper motor thats ups the idle when it switches on... tho its inoperative on my car now.

[JohnelP]

yes, there is air conditioning installed. Makes sense, now to increase the rpm when idle and AC is turned on?

Flashmn, do you have any clue what could be the device bolted on the rear of the intake manifold?

Maybe in Finland, you didn't need all the emissions stuff, but just in case.

[Flashmn]

Then again your car is fuel injected... it shouldnt have the valve for the aircon, because thats a carb corolla part....

[automatic]

Auto cars have that also.
There are several electro-air valves for other reasons, depending on year, model, I've noticed from cruising the boneyards.

[JohnelP]

Ref. the question about the roles of some "elements" in the engine.

Now I made some photos of these elements I tried to describe above and I do not their meaning (role). The element marked with 2 is somehow related to the power steering.
The elements 1 and 1' are connected with 2 hoses, and also, i do not know their roles.

I put the pictures under the following link:



http://alexan.freehomepage.com/photo5.html



The same elements are photographed from different positions.

Any help?

[TekPhobia]

Originally posted by JohnelP
Ref. the question about the roles of some "elements" in the engine.

Now I made some photos of these elements I tried to describe above and I do not their meaning (role). The element marked with 2 is somehow related to the power steering.
The elements 1 and 1' are connected with 2 hoses, and also, i do not know their roles.

I put the pictures under the following link:



http://alexan.freehomepage.com/photo5.html



The same elements are photographed from different positions.

Any help?

"Element" 1 contain the A/C idle-up VSV (Vacuum Switching Valve), attached to the firewall, and the bypass, the doohickey with the white knob.

Number 2 is the ACV. The vac tube connects to a vac pipe which is secured to the bottom of the intake manifold with 2x10mm nuts. From there, it's connected to the bottom of the intake silencer -- the hollow container between the airbox and the manifold. The ECU will pulse the ACV in order to bypass air around the TB. You're supposed to disconnect it when you check the timing, too.

-Tim

[JohnelP]

Thanks!!!

Do you mean with "TB" throttle body? Why do you need a second bypass of the throttle body. The idle speed control valve (ISCV) is ot enough? ISCV is near the throttle body, isn't it?

Is ACV the same thing with ISVC? At least in Haynes book ISCV looks different, but maybe in Haynes the pictures are for different engine models.....

[TekPhobia]

Originally posted by JohnelP
Thanks!!!

Do you mean with "TB" throttle body? Why do you need a second bypass of the throttle body. The idle speed control valve (ISCV) is ot enough? ISCV is near the throttle body, isn't it?

Is ACV the same thing with ISVC? At least in Haynes book ISCV looks different, but maybe in Haynes the pictures are for different engine models.....

Yes, TB=Throttle Body.

Hey, I just tell what I know Toyota does their own thing.

I think you'll find this interesting:

http://www.autoshop101.com/autoshop15.html

There's an entire article on idle speed control. I also got a ZIP file with the same, plus more of the documents.

-Tim