# Does anyone know the idle adjustment procedure for a 1986 Stanza Wagon?



## alank2 (Dec 29, 2006)

Hi,

It seems someone thought adjusting the accelerator pedal cable was the way to adjust the idle on this fuel injected model.

Any idea how I should adjust the accelerator pedal cable properly, and then adjust the idle properly?

It runs at about 1300 rpm when in park or neutral.

Thanks for your help in advance!

Alan


----------



## bikeman (Dec 26, 2006)

alank2 said:


> Hi,
> 
> It seems someone thought adjusting the accelerator pedal cable was the way to adjust the idle on this fuel injected model.
> 
> ...


Just back the cable adjuster till it's no longer pulling. If idle is still high check timing since too far advanced will give high idle as well as pinging when motor is pulling(uphill/take-off). Also check all vacuum hoses, there are a lot of little hoses around and at that age they often crack right where they connect and not visible until you bend the hose a little.
Make sure throttle body/butterfly area is clean(clean with throttle body cleaner and a tooth brush) and linkages are not sticking.


----------



## KA24Tech (Feb 2, 2004)

Bikeman is exactly right. The vacuum hoses are usually the problem with a high idle when at operating temp.


----------



## alank2 (Dec 29, 2006)

Hi,

Thanks for the posts guys.

I'm going to adjust the cable until there is barely any tension on it. I think the reason it was turned up was that it runs rough when there is no tension.

I don't know if anyone messed with the idle screw or not - is that the flat blade screw that faces up that looks like it is about 1/2" wide? If I remove the cable tension and it is running rough, should I try to adjust the idle screw to see if that will fix it?

And then look at the vacuum hoses? I saw a diagram of vacuum hoses on autozone. What do you check on a vacuum hose - just make sure there aren't any cracks or leaks?

Thanks for the help,

Alan


----------



## bikeman (Dec 26, 2006)

Just visually check hoses for breaks. My repair manual shows an idle screw adjuster but first have to drill a small hole to expose it, besides rough idle wouldn't be because of idle speed unless it's really low (should be around 700rpm in drive). That screw you're talking about does not adjust idle, at first idle goes up then computer adjusts it back down, leave that alone. Check also the big air shroud from air filter box to throttle body as you may have a split in it, grab it while idling and move it a little to see if this has an effect on idle. Mine once had a split underneath where I couldn't see and evertime I put it in gear the idle would drop and sometimes even stall. Don't forget the basics: plugs, wires, cap & rotor.


----------



## alank2 (Dec 29, 2006)

Hi Bikeman,

Thanks for replying and the tips. I did adjust the throttle cable until there was no tension on it. I then turned the idle screw counter clockwise about 1/2 turn. Now it will start up and idle at around 1100 rpm when warm and when in drive will run around 700 rpm. If I turn it down so it is running a little slower it idles roughly when switching into drive or reverse. At this current setting I can go from park to reverse/drive without any roughness. I still wish it would idle a little slower when in part or neutral, but maybe that is a vacuum hose, which takes me to my next question:

I am having a noise that occurs most when in drive and not moving (braked pressed). It is a sort of vibrating whirring noise for about 1 second on, then it stops for 4-5 seconds and then repeats. Sometimes it won't do it for 20-30 seconds. If it is in the middle of the noise and I let up on the brake, it goes away. I thought perhaps it only happened in drive/reverse, but after putting it in park, it happens too, just not nearly as much.

Do you think the noise is a vacuum hose? I'll have to get some more time under the hood when it warms up and take a look.

Thanks for the help,

Alan


----------



## bikeman (Dec 26, 2006)

Hi Alan, that idle is still high, should be 900 in neutral, 700 in drive, you've got quite a drop when put in drive. Is that the 1/2" screw you mention in other post that you are adjusting? I don't think that's an idle adjuster, maybe mixture. Check all the little hoses and while you're at it check PVC valve, often neglected since out of sight and hard to get at. Make sure timing is not too far advanced, are you getting any pinging under load? Check throttle valve switch connection as well, I've had a bad connection at this unit give me problems, it's the flat black unit mounted on the throttle body. When vehicle is 20+ years old wires and hoses just harden and break.
That whirring sound may be your fuel pump working, the FWD has the pump mounted to underside of car just below the rear right passenger and can be heard working, the AWD version is in the tank. When you turn your ignition on, not cranking position, you should hear a hum for a few seconds and then stops, is this the sound you hear? Do this with radio off, seat belt on and door closed so no other noises get in the way of hearing for it.
good luck........Louis


----------



## alank2 (Dec 29, 2006)

Hi Louis,



bikeman said:


> Hi Alan, that idle is still high, should be 900 in neutral, 700 in drive, you've got quite a drop when put in drive. Is that the 1/2" screw you mention in other post that you are adjusting? I don't think that's an idle adjuster, maybe mixture.


It seems to have a direct correlation to the idle. Maybe I'll try turning it down just a little more and see how it idles in drive. It is a silver colored screw sunk down into a threaded hole maybe an inch or so. Standing at the front of the vehicle, it is to the front-right of the engine and faces directly up.



bikeman said:


> Check all the little hoses and while you're at it check PVC valve, often neglected since out of sight and hard to get at. Make sure timing is not too far advanced, are you getting any pinging under load? Check throttle valve switch connection as well, I've had a bad connection at this unit give me problems, it's the flat black unit mounted on the throttle body. When vehicle is 20+ years old wires and hoses just harden and break.


I don't have the necessary skill to do these things unfortunentely! I can probably check the hoses, but I don't know how to check the PVC or timing. I don't think I'm getting any pinging. Wouldn't that show up when I accelerate had? That isn't the case as far as I know.



bikeman said:


> That whirring sound may be your fuel pump working, the FWD has the pump mounted to underside of car just below the rear right passenger and can be heard working, the AWD version is in the tank. When you turn your ignition on, not cranking position, you should hear a hum for a few seconds and then stops, is this the sound you hear? Do this with radio off, seat belt on and door closed so no other noises get in the way of hearing for it.


I don't think it is that. If I turn the ignition on slowly I can certainly hear the fuel pump whirring away. The fuel pump is making a higher pitch sound that the whirring I'm talking about. Any other ideas on the whirring sound I should look at?

Thanks again,

Alan


----------



## bikeman (Dec 26, 2006)

Alan, on my '87 the idle screw is at the right side of motor(accessory belt side) facing up on an angle toward the firewall, it too is sunk in a little. Is this the screw? I thought you were referring to another. If you don't have pinging/rattling when taking off or climbing hills don't touch timing. The hoses are easy to check, just bend them back at connections to see if they are cracked. The PVC valve is inexpensive, just replace it, most likely it has been in there a long time. Easy enough to change just awkward to get at since you have to un thread it with very little room to work. It's straight down just in front of where the idle control unit is with a hose about an inch in diameter coming straight off it. Can you stick your head under the hood and poke around while it's running and listen for the whirring? If it's that steady maybe you can pin point where it's coming from. louis


----------

