Mechanics

GX VACUUM HOSES

1989 Toyota Corona • 4 cylinder FWD Manual •

Hi,
I have a Japanese made Toyota Corona GX 1989 MTM with 5AF engine. Please help me to fix my vaccum hoses for Air Conditioning. Previously, Some one has removed and messed up with the hoses and now i'm having problems when car is ideling with AC on. I've got some diagrams of the vaccum hoses from the net for AC unit, but i'm not sure with some hoses which goes into the Carb.
It is vermuch appriciated if you can get me some pictures of a real 5AF engine with proper vaccum hose connections or a repair manual.
Thanks in advance.

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Udaruk
May 1, 2011.



Our database does noty have any information on JDM nmodels so I am not able to get any diagrams for you.

If the hood is original, under the hood panel you would find a vacuum schematic diagram if it is still there.

If it is only the A/C vacuum lines, that would be easy to resolve. One line for the idle-up control solenoid goes to the intake manifold, it has to have constant vacuum when engine is running.

Vacuum lines have to installed correctly, reversing the installation of the hose would result in idling speed increasing when vacuum is turned off as the vacuum pump is not released. During initial start up, the engine idling would be erratic after the automatic choke has turned off due to vacuum leakges at the solenoid. Reversing the hoses at the solenoid should solve the problem.

The constant vacuum line should be attached at the outer of the two joints.


KHLow2008
May 1, 2011.
Hi,
Thanks for the quick reply, being new to these type of things and various answers from the local michanics made me totally confused.

The label under the hood is faded and unreadable. There are 4 hoses totally detached and hanging from the devices on mountings.

Please refer the picture i've attached here with. I've marked the hoses in question as A-D in it.

Thanks


Tiny
Udaruk
May 1, 2011.
Where these hoses lead is not clear from the diagram. They seem to be emisison related. D seems to be joined to the EGR valve. As to A, B and C, dose it go to any components nearby?

Are all these hoses and the joints present in your vehicle?


KHLow2008
May 1, 2011.
Yes all the hoses and the joints are there except one "T" joint with the 4 connetors. Instead of 4 connections it has only 3 connctions. (You can see it right bottom side of the diagram)

there are some T connetors below the air filter and the Carb, colse to hoses A and B, which is not connected to anything. I'll try to get a picture of the engine and post it where you can see it clearly.

One extra question, I have recently saw a hose from the Canister is also going nowhere. Should it go to one of the vaccum lines also.

Thanks for your expert opinoins


Tiny
Udaruk
May 2, 2011.
Yes, the cannister hose should also be joined to the carburettor but it is a vacuum free liine as it is for vapour released from carb to go out.

Where did you get this diagram from? For the 3 or 4 point joints that you mentioned, one could possibly be for the A/C line as standard vehicles are designed without any A/C and usually there are some extra ports. On the other hand if the diagram is not for JDM, different markets might have additional emission controls that are not used in Japan.

I have a few diagrams here for the 4-AF engines. See if it is of any help to you.


KHLow2008
May 2, 2011.
4AF and 5AF engine diagrams are same? If not what are the general differences they have?


Tiny
Udaruk
May 2, 2011.
They should be similar.


KHLow2008
May 2, 2011.