Adjusting idle on fox body 5.0 - Northern California Ford Owners

This is topic Adjusting idle on fox body 5.0 in forum Tech Talk at Northern California Ford Owners .

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Posted by Clark (Member # 1076) on :

Alright, I got a mass air conversion all done. I like the idle, but I just need it bumped up 100 RPM's or so. I heard how to do it earlier in the night but I forgot what you have to unplug.

Do you unplug TPS sensor and then adjust it, and then plug TPS back in. Or the big cylindrical thing and then adjust and then plug back in???

I totally forgot how to do it, any help would be greatly appreciated. Thanks! [patriot]

Posted by Black94 5.0 (Member # 655) on :

The "big cylindrical thing"...(Idle air control valve)Unplug that then you can adjust your idle screw..
[patriot]

[ January 18, 2003, 11:58 PM: Message edited by: Black94 5.0 ]

Posted by Clark (Member # 1076) on :

OK SO, Basically I

1. Start car
2. Unplug IAC
3. Adjust Idle
4. plug IAC back in

That's correct?

[Confused]

Posted by st5150 (Member # 51) on :

If you're lazy like me, just tighten the idle screw and the EEC will figure out the IAC stuff in a minute or so. This works if your TPS isn't set really close to 1 volt. Either way is fine. Just make sure you don't tip the TPS over 1 volt by tightening the idle screw.

Posted by Black94 5.0 (Member # 655) on :

quote:
Originally posted by Clark:
OK SO, Basically I

1. Start car
2. Unplug IAC
3. Adjust Idle
4. plug IAC back in

That's correct?

Yes that's correct! But like Sawson said, after you set up your idle check to make sure the TPS is no more than .998 volts!
[patriot]

Posted by Clark (Member # 1076) on :

thanks! [patriot]

Posted by 91PONY (Member # 206) on :

Here's the procedure from Corral.net...

Clear the EEC-IV's idle memory by disconnecting the battery for 20+ minutes.
Disconnect the Idle air bypass solonoid
Reconnect battery
Start engine and set idle speed to desired RPM with stop screw on throttle body (900 rpm works great with E303 or larger cam)
Turn off engine and reconnect the air bypass solenoid
*Optional -- set TPS to 0.90 - 0.95 volts (Do not exceed 1.0 volts MAKE SURE!) Use a digital volt meter!
Start engine and let it idle for 2 minutes with no accessories on.
Turn off engine for two minutes
Start engine again and run for 2 minutes with every accessory turned on.
Turn engine off again.

Your computer should have now re-learned the new idle settings. This procedure assumes that you have a clean IAB valve. If it is carboned up then you may need to remove it and clean it with carburetor cleaner.

~Heather [patriot]

Posted by st5150 (Member # 51) on :

I guess this proves I'm the laziest, Black94 5.0 is a little less lazy and corral.net makes everything complicated [Wink]

The real reason I replied....

Use a Penny to tighten the idle screw. It fits and works perfect since I don't have a stubby flat head.

Posted by 91sleeper (Member # 779) on :

Whata re al of you guys idleing at? Would you benefit any from bumping your idle up to around 900 from say 700??? Wonder if my auto would be able to get out of the whole a little better maybe?

Posted by Black94 5.0 (Member # 655) on :

Thats some funny shit Sawson!!...you are very resorceful...What are your uses for dimes and quarters? [Big Grin]

Posted by st5150 (Member # 51) on :

Dimes and Quarters? Too precious! If I had dimes and quarters, you'd think I'd just buy the stubby flat head I need to adjust the idle screw [Big Grin]

91sleeper- what you need to get out of the hole faster is a 3000-3500 RPM stall converter [burnout]

[ January 19, 2003, 12:27 PM: Message edited by: st5150 ]

Posted by Black94 5.0 (Member # 655) on :

quote:
Originally posted by 91sleeper:
Whata re al of you guys idleing at? Would you benefit any from bumping your idle up to around 900 from say 700??? Wonder if my auto would be able to get out of the whole a little better maybe?

...I think you would just be wasting gas,if you put the idle up to 900RPM...If you want your auto to get out of the hole better, have you tried stalling it? (Putting your feet on the brake pedal and the accel. pedal at the same time) [burnout]

Posted by 91sleeper (Member # 779) on :

quote:
Originally posted by st5150:
Dimes and Quarters? Too precious! If I had dimes and quarters, you'd think I'd just buy the stubby flat head I need to adjust the idle screw

91sleeper- what you need to get out of the hole faster is a 3000-3500 RPM stall converter

Actually i am saving for a 5 speed swap.

Posted by 91sleeper (Member # 779) on :

quote:
Originally posted by Black94 5.0:

quote:
Originally posted by 91sleeper:
Whata re al of you guys idleing at? Would you benefit any from bumping your idle up to around 900 from say 700??? Wonder if my auto would be able to get out of the whole a little better maybe?
...I think you would just be wasting gas,if you put the idle up to 900RPM...If you want your auto to get out of the hole better, have you tried stalling it? (Putting your feet on the brake pedal and the accel. pedal at the same time)

Yeah I have brake stalled, the stock converter sucks alot it has like zero stall speed. Thats why my times are so slow. I am just going to do a 5 speed swap. That will pick up my times a lot and the fun factor. I want to be able to do cruises and take my car to some open track events like Thunder hill. It kinda sucks doing twisties with an auto.
[Roll Eyes]

Posted by Clark (Member # 1076) on :

ALRIGHT! MUHAHAH, I get it now!!!

Thanks everyone, You guys are so smart! [patriot]

Posted by Clark (Member # 1076) on :

Something's not right [Mad]

Now, when I downshift, it backfires. And throttle takes days to get back down if that makes sense.

Now, I did it correctly. I took off and I could totally tell something's wrong. When I rev it, RPM's would drop like they should. Now it takes a while to get RPM's back down. Any suggestions? Is there a way to turn it back? [Confused]

Posted by Clark (Member # 1076) on :

I guess what I mean is, Can I start over now??? [Confused]

Posted by st5150 (Member # 51) on :

Sounds like you tightened the idle screw so much, the TPS is now over 1 volt.

[ January 19, 2003, 03:40 PM: Message edited by: st5150 ]

Posted by Clark (Member # 1076) on :

So is the TPS bad now? I don't have a voltmeter, How much are they? [Frown]

Posted by Clark (Member # 1076) on :

double post

[ January 19, 2003, 03:48 PM: Message edited by: Clark ]

Posted by st5150 (Member # 51) on :

Its not bad, but probably not adjusted right. Get a digital volt meter. They're always on sale at Harbor Freight. $10-25 and it'll come in very helpfull throughout your life.

Posted by Clark (Member # 1076) on :

The idle was just about as good, is there just a way that I can put it back where it was???

Posted by st5150 (Member # 51) on :

I'm not sure I understood that fragmented sentence, but if you want to go back to the way it was simply undo what you just did.

Posted by J's DDLY SNK (Member # 2016) on :

Turn the car on and let it warm up a few minutes (5).
Remove the IAC and adjust the idle to 500-600 RPM. There is usually a gold/coper like screw on the Throttle Body (BBK) or a silver one on the Ford models.
Place the IAC back on and the car will return to computer controlled idle.
Turn the car off after a few minutes.

Then with a voltmeter set the TPS at .99 -.97 volts.(or as close as you can get without going over.99)
Turn the ignition on but dont start the car up, just keep it in the on position.
Connect the positive lead of the meter to the grey w/ white strip.
connect the negative lead of the meter to the grey w/ red strip.
Once you reach the desired reading tighten down the TPS.

Posted by Clark (Member # 1076) on :

Everytime I unplug the IAC the car dies! [Roll Eyes]

Posted by st5150 (Member # 51) on :

That could be a hint that you need to tighten your idle screw. Can you start the car and have it idle with out the IAC connected?

Posted by J's DDLY SNK (Member # 2016) on :

quote:
Originally posted by st5150:
That could be a hint that you need to tighten your idle screw. Can you start the car and have it idle with out the IAC connected?

Keep tightening until it idles right. its not a 5 min job, take your time.

Posted by Clark (Member # 1076) on :

Well when I tightened it down, and drove it around like that it started backfiring when I downshifted. So I thought it needed to be looser???

Damn I shouldn't have messed with this thing! [Mad]

Posted by st5150 (Member # 51) on :

when you tighten the idle screw, you also increase the TPS voltage. Back off the TPS when you tighten the idle screw.

Basicly, everything that could be said on the topic has been said. Start back from the first post and slowly read each reply and you'll be fine.

Posted by darien87 (Member # 2022) on :

Hey Sawson, when you say adjust the idle screw, what screw are you referring to? I've adjusted a small nut that's under the throttle body and connected to the throttle cable. Is this the "screw" you're referring to or am I messing with the wrong thing?

I've been trying to fix my idle problem ever since Mustang Ranch drilled a hole in my throttle body. The damn car's never idled right since.

Here's what it does, basically every time I put the clutch in the car wants to stay at whatever RPM I was at, (i.e. if I'm rolling to a stop at 1,500 RPM's and put the clutch in, the car stays at 1,500 RPM's). The RPM's come back down if I tap the gas pedal. Sometimes it even jumps up from idle to 1,200 RPM's or so. I've cleaned the IAB, done the 10-pin thing, and still it keeps doing this. The last time I checked the TPS, it was at about .85 volts. I think that was before I messed with the idle nut though.

Will the Corral.net procedure help my problem?

Posted by st5150 (Member # 51) on :

What brand / size throttle body do you have?

The corral.net proceedure is a joke, don't believe everything you read online. There is a lot of bad info floating around these days.

Is your TPS bad?

Have you tried partially covering the hole Mustang Ranch drilled with duct tape to see if it helps? Why did they drill it in the first place???

Posted by Cobra5.0Jeep (Member # 1482) on :

Hey i did that procedure from Corral.net and now my Idle is back down to 700 and i set it at 900 what gives? [Confused]

I am gonna go tighten the idle screw but i want my idle to STAY at 900 not drop down after a couple of months.

Posted by st5150 (Member # 51) on :

CobraJeep. The only thing worth while in that corral "how-to" is unplugging the battery... but there is no real need to do that because the EEC will learn its way regardless. The reason your idle drops from 900 is because the EEC isn't programed to idle it that high. Eventually the EEC is "learning" around your tightened idle screw and returning back to what it was programmed to do. Get a twEECer or a chip from Byron and have your car set to idle where ever you want.

Posted by 91PONY (Member # 206) on :

quote:
Originally posted by st5150:
The corral.net proceedure is a joke, don't believe everything you read online. There is a lot of bad info floating around these days.

Ahem....well it worked for my car! [Wink]

Posted by st5150 (Member # 51) on :

Sorry, I was a bit harsh. I didn't mean to imply that method doesn't work... I was just saying its MUCH more complicated than need be and has useless witch doctor type steps in there like turning on and off all the accessories. I'm surprised they didn't talk about doing the rain dance backwards to please the EEC idle gods in the sky and tossing chicken bones in the witches brew in that "tech" artical [Wink]

Simply adjusting the screw and letting the EEC learn the new settings in time or unplugging the battery for a few seconds both are valid methods. No rain dance needed [Smile]

Posted by darien87 (Member # 2022) on :

Hey Sawson, I have an Edelbrock 65mm TB.

I don't think my TPS is bad. Apex replaced it a few months ago when I was trying to track down a backfiring problem.

Joe at Mustang Ranch was trying to alleviate that throttle body whistle that most of the aftermarket TB's seem to have. It got rid of the whistle, but now my car won't idle right.

Posted by st5150 (Member # 51) on :

The cure is to get a ford 65mm TB. I don't know what else to tell you.

Posted by Cobra5.0Jeep (Member # 1482) on :

i adjusted the idle and its fine now, hopefully it stays that way. I can't afford a chip and i don't think i can get my Jeep dynoed anywhere anyways i think my 35s would break the dyno. I need a new tranny and rearend and i have almost enough money to do it.
Dana

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