Hello,

I am having a little trouble getting my Holley hp and sbf to idle correctly.

I have a tuner asking me to open throttle plate more to let more air in at idle and a crazy whistle/hiss sound coming from around IAC area. I have fresh gasket that came with the accufab adapter on it. I have the push in Chrysler stepper IAC

On the tune he is seeing way too high of IAC open %.


Professional products 70mm TB

On the throttle plate when I turn the nut, I have the screw as far clockwise as possible to turn. I could see the right side of the throttle plate moving towards the intake when I turned this.

I question if I have been turning the plate the wrong direction this whole time. Do I need to go the other direction and have the plate go more towards the IAC hole closer to the air intake side and reduce opening towards intake manifold?



Thanks

 

As you open the TB setting at idle the IAC will close. I like to see the IAC at about 20% at my command idle speed. If the IAC is open too far to get your idle speed, you can have stalling problems with a sudden throttle lift.

Remember, everytime you adj the TB opening, you have to perform a TPS autoset or you'll be chasing your tail and going crazy!

 

If I have the throttle plate as far as possible clockwise against the nut and throttle body housing bottom what other options do I have?

I can turn the screw the other way which I am worried will close it more as the right side of the blade goes towards the intake manifold side.

Is the option to try out my old ford IAC spacer adjustable plate back on to try? I would need to see if it is compatible with accufab adapter opening.


Thanks

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Are you sure the IAC is functioning? Seems I remember reading about some wiring issues with the Chrysler IAC.

 

Are you trying to adjust that plate, or are you using the idle set screw on the back of the TB? I'd be using the idle set screw right now. You should be able to get it to idle without the IAC hooked up.

 

I went with the Chrysler and added cost of the accufab adapter so I wouldn’t have to mess with the pins in the wiring from Holley.

It wouldn’t surprise me a bit if the IAC wasn’t functioning properly. I know it is making a lot of noise with a whistle and hiss after install.

The tuner looking at my data logs from start in garage only mentioned that the percentage open was far too much.

I hope I didn’t waste all that time Dremeling the screw holes for nothing

 

Have I been doing it wrong all this time? I was adjusting the screw and loosening the nut underneath the throttle body.

It’s not a valve but like a little plate that hits the end of the screw. I have the screw all the way in and nut is up against screw head and throttle body bottom

I’m trying to open this plate and attempt to let more air in to get the car closer to the spec Holley wants for IAC opening

Thanks

 

By plate,you mean the throttle, yes?

Like Disney said,you should be able to get it to idle without the IAC. You can remove it and tape over the holes,get the speed you want,then reinstall the IAC. It should be pretty much at zero opening then as long as the commanded speed in the software is the same as you set it without the IAC.. If not, something's up.

 

Yes sir. I was first trying to get the plate open to let more air in. At first we couldn’t even get the car to start the plate was closed too much so I turned screw all the way right to get the pictured throttle plate open that far.

I will remove the IAC and tape up if I cannot find a way to get this throttle plate open more.

Thanks

ETA I hope I didn’t confuse anyone. This is the stop screw I have been trying to adjust, I have not noticed any other options on the professional products tb to adjust.

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If you can't get enough adjustment, maybe try removing the nut from the screw.

 

Would my safety be compromised if I went to the hardware store and tried to find a longer screw to keep the stop further to the right and plate open more?

I’d rather try this as safe as possible and not worry about safety.

Thank you very much Brian

 

Sure,longer screw.

 

Heading to hardware store, will post pics after.


Hey on the Holley software when checking static riming what number did you try with Brian? Would 20 degrees static timing be good as a test with the timing light? This is with the 565-201 dual sync on hp software

Thanks man!

 

Yes, 20* will work.

 

Thanks Brian for the amazing help. Wish I had a guy with half your skill around here.

 

close the blades all the way .

TPS auto set .

open blades until you see 2% on the tps .

Do another TPS auto set .

Adjust IAC parked setting .

 

I’m going to re check this again tonight and weekend. Tuner could not get the car to start with blade as closed as I had it. I’d like to push the car out and see if I can get the car to run on it’s own while messing with the throttle stop screw.

I just got my new longer screw from the hardware store to keep blade open.

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Hard starting is either IAC parked setting or cranking fuel .

If the IAC is working .

Just for comparison , heres my perimeters . Its a 383 sbc but we put it in my buddies 351 and it started fine .

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Cranking fuel[/url] by David Cedoz, on Flickr


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IACparked[/url] by David Cedoz, on Flickr


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Afterstart[/url] by David Cedoz, on Flickr


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afterstart2[/url] by David Cedoz, on Flickr

 

Can you see the pics ?

 

one more


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