Idle issues for VS commodore engine

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tree101
Here and there
Posts: 42
Joined: August 5th, 2014, 2:33 pm

Idle issues for VS commodore engine

Unread post by tree101 » March 26th, 2015, 5:06 pm

so basically my 4runner (which has a vs commodore engine in it) is having some strange issues. for starters when it starts, if no accellerator is added it will stall almost instantly. if the accelerator is played around with for a bit the my foot released it will idle but the RPM arent very constant and it causes abit of stuttering, also at this point if i tap the acclerator towards me the engine will stall again. its really strange and im not mechanically minded so im not sure what to do. we have already replaced all the spark plugs, leads and oil but the issue is still here, any help would be great as its my first car and up till now shes seemed great.

ill also upload a video to show the things im talking about.

http://youtu.be/-UmEL6cSf8Y

also another issue ive had which you guys might be able to help me with, when i first turn the key to turn on the car, it doesnt try to start it (cant here any clicking or anything) so you turn the key back and then try again and itll start and i dont have a clue why

Jimmy Wood
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Posts: 637
Joined: July 26th, 2013, 4:06 pm

Re: Idle issues for VS commodore engine

Unread post by Jimmy Wood » March 26th, 2015, 8:33 pm

Sounds and looks like the throttle cable needs to be adjusted doesn't it. Lifting the accelerator from its rest position shouldn't move the throttle at all. It means the cable and accelerator are not adjusted right. Probably a dodgy install job.

First of all, go and get yourself a Gregorys workshop manual for the VS and the Hilux. It will be an excellent guide.

Make sure the cable is all free, and not burred or split near the ends, and that all linkages are free. Lube them all up a bit. Maybe use graphite on the cables.

Get it idling like you had it, then get someone to lift the accelerator like you did, and with you looking at the throttle body under the bonnet, see if it moves the throttle body at all as they lift it. If so, you need to adjust the cable so that when the accelerator is right up (which the spring should hold it right up too, so check that) the throttle is against the idle stop screw. Then, when that is sorted, see if it idles.

Those motors use an IAC valve to control idle speed. Its a little electrically controlled valve in the throttle body which opens and closes to change idle speed. Sometimes when you remove the battery cables, this valve needs to be reset. To do this, start the engine, and run it at 2500 RPM for a few mins (2 - 3 mins) then see if it resets to idle.

If not, you should clean up the IAC valve and passages (take the throttle body apart to do it properly). Use carby cleaner or petrol. Make sure all wires are on and connections tight.

You may find that the idle stop screw needs to be moved out a bit, to hold the throttle open just a fraction more, then the IAC can do its job. It only has a limited amount of movement, so if throttle plate is too far closed, or all dirty and gummed up, it can't allow enough air to idle.

With the key thing, sounds like a sticky key switch or something - again, probably dodgy install. Does it do it all the time, or just a bit. What if you just hold it there for a few seconds more, does it try and start then?

Hope this helps.
Jimmy

tree101
Here and there
Posts: 42
Joined: August 5th, 2014, 2:33 pm

Re: Idle issues for VS commodore engine

Unread post by tree101 » March 26th, 2015, 8:38 pm

wow, thanks for the help jimmy, my brother thought it would be one of those two things aswell, we will take a look on the weekend. thanks for the how to as well. as for the key its constant and doesnt do anything if i hold it there for a little while

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