high, steady, idle...

[tim_korn_99]

I've read through all of the fast idle pages, and none of them seem to have the same problem as me.
First of all, when i start my car, and the engine is cold, the idle will jump up to about 2000rpms, and over the next minute, it will climb up to about 2500rpms. It stays there and is very steady. It will eventually go down to about 2200 to 2300rpms after the car has fully warmed up. No surging or anything that seems to be associated with the FIAV or the ISC.
Another thing, i adjusted my BISS all the way in, and thats how i got the idle THIS LOW. Which isnt low at all...
This next part pertains to the next question:
I'm only running 1 fan on my radiator, because of my 16g install kit, and so, earlier this summer, when it was still hot outside, i could let my car sit and idle (high) and as it began to "heat up" above 220 and between 235 the idle would go down as it heated up. But it never got below 1800 rpms, and that was when the engine temp was at 235. I never let it go above that...
SO, my question on this is, if it was a vac leak, would it change like that?

Another note, when i adjusted my BISS, i just hooked my palm logger up to it, and turned the screw in. The idle followed accordingly, but never dropped to "normal." Is that the correct way to do it? I know the VFAQ says to center the ISC, but i don't have a way to do that. Do i have to pay a shop to do it?

Thanks
-Tim

 

[tim_korn_99]

Today i sprayed all visible vacuum lines, and found no leaks. However, there was one vac line off. It was on one of the three solenoids on the firewall, behind the intake manifold. It was the one that was directly behind the throttle body, and it would be the one furthest to the passenger side of the car of the three. I felt the line to see if it was even under vac, but it wasnt. I plugged it back in, and it did nothing to the idle. I also checked the throttle body butterfly stop screw, and it was adjusted correctly.
Are there any more vac lines that are out of sight? I know there are a few that go back down behind the intake manifold, but would the affect the idle?
And, does anyone know what that solenoid was on the firewall?
Thanks
-Tim

 

[siceclipse]

i have a possible answer for you. I just got my car back yesterday from Mits. The mechanic working on my car said that with all the free flowing parts on my car, such as I/C piping, exhaust, intake, my ECU is able to flow the air a lot faster there-fore it advances the intake timing. So I asked hom evactly what that meant and he said that usually the IAC and everything are set aroung 7 Ohms. Mine had advanced to 50. Go have them check it. Its worth the $80 and if it fails in 90 days or 4000 miles they will check it for free.
Try it, its worth the shot.

 

[zxdude]

this might be too simple but I had a bad connection to the iac and it did the same thing... also your throttle cable could be too tight ... holding the TB slightly open ...

Adam

 

[94EclipseGST]

Yes, could be the throttle cable is too tight. When I changed my FIAV, I stupidly removed the spring and then when I replaced it, I wound it one time too tight. That made the idle stick at like 2000 RPM.

It could also be that the TP switch is open too much. Did you mess with this?

 

[grans0o]

I had a high idle and was instructed to adjust the BISS while the engine was shut off so the ECU wouldn't fight the idle adjustments I was making with the BISS. What I would try is to:

1. Unscrew the BISS all the way (it shouldn't fall out)

2. Start up the engine and run it for a minute or so (so the ECU can sort of reset itself, the idle should be pretty crappy with the BISS unscrewed all of the way.)

3. Turn off the car.

4. Tighten the BISS all the way down and then back it out 2 turns.

5. Start car back up, if idle is still too high. Turn off car and screw the BISS in more and repeat if necessary.

Hope this may be of some help, I am no expert on this.

 

[tim_korn_99]

What is the TP Switch? Do you mean TPS? The throttle cable is not too tight, i checked that. I'll check the connection to the IAC tonight.
I dont really think that i have the same problem as siceclipse, but if i dont figure something out, i'll give that a shot. Reason being, all the mods were on the car and working fine for quite a while.
This problem seemed to just SLOWLY get worse over the course of maybe a week. That was a couple months ago. It started out as the idle being about 1200 rpms, then over a period of a week, it slowly progressed to where it is now, about 2500 rpms.
I'll check it out some more tonight, and let you guys know.
Hopefully i can get this fixed, its driving me nuts.
Thanks for all the replies!!!
-Tim

 

[ADrewzki]

Have you tried simply resetting the ECU and putting the biss screw where it's supposed to be? I remember when mine did this and all I did was take the battery terminal off for an hour and it idled normally afterwards.

 

[tim_korn_99]

Have you tried simply resetting the ECU and putting the biss screw where it's supposed to be? I remember when mine did this and all I did was take the battery terminal off for an hour and it idled normally afterwards.

That was also one of the first things i tried. I left the battery unhooked overnight. Still the same thing... I checked the connections to everything under the hood, and they are all tight.
So, i've ruled out.....
1. Throttle cable being too tight
2. Loose connection
3. Reset ECU
4. Vac leak

I'm guessing it has something to do with either the ISC, or the FIAV. How do i check those?
Thanks
-Tim

 

[tim_korn_99]

ok, i did a boost leak test today, and this is what i found.
at about 5 psi, my RFL (really f**in leaks) BOV was leaking around the base. I RTV'd the crap out of it, and fixed it. After that was fixed, at around 6 psi, the throttle body shaft seals were leaking like CRAZY. The more i opened the TB, the louder it got. So, gotta get those fixed. Do you think that would cause my high idle?
-Tim

 

[tim_korn_99]

Well, i picked up some new o-rings, and seals for the throttle body. I decided to do it before it got dark. Record time....
I replaced the seals, and figured since i had it all apart, i would block off the FIAV, just to rule out one more possibility. I rerouted the water lines. And i thouroghly cleaned the throttle body out. It all went without a hitch. Got it all back together, started it up, and it idle at about 1500 rpm. I thought, wow, that's lower. But, as it began to warm up, UP went the idle... now its like 2800 RPMS!!!! 300 HIGHER than it was before!! WTF??!
I drove it up the road and noticed how much smoother the car ran now that it didnt have a huge boost leak. But still, the idle is killing me here... what should i do next??
-Tim

 

[tim_korn_99]

no one knows anything about this????

 

[howie3]

i have a possible answer for you. I just got my car back yesterday from Mits. The mechanic working on my car said that with all the free flowing parts on my car, such as I/C piping, exhaust, intake, my ECU is able to flow the air a lot faster there-fore it advances the intake timing. So I asked hom evactly what that meant and he said that usually the IAC and everything are set aroung 7 Ohms. Mine had advanced to 50. Go have them check it. Its worth the $80 and if it fails in 90 days or 4000 miles they will check it for free.
Try it, its worth the shot.

This sounds like your problem. Can your IAC be adjusted? If so you should at leased give it a look into. Does anyone know how to adjust it? Just my .02.

 

[tim_korn_99]

I unplugged the IAC, and it did the exact same thing as it has been doing. When cold, idles at around 2000, as it warms up, idle climbs to 2700 rpms. I didnt get a CEL or anything either. Does that mean anything?
Also, when i blocked off the FIAV, I just re-routed the water lines, should i go back and actually block off the air outlet?
Thanks
-Tim

 

[tim_korn_99]

Ok, i pulled the throttle body back off. 2nd time is always easier...
First thing i did was test the Ohms of the coils in the ISC, per instructions given through the VFAQ. All of them measured in at 29 ohms. Perfect. Next, i took the ISC off of the throttle body, and hooked it up to the car, and had my friend turn the key to ON. The ISC responded, by pulling the pintel inward. Then, when the key was turned off, it released itself outward. So, that means that the ISC is working correctly.
That leaves one more thing, which would be the FIAV. I re-routed the lines last night, but didnt take the time to actually block off the FIAV. I'm going to do that right now. HOPEFULLY, that should fix my problem........ I dont think there is anything else left, right???
-Tim

 

[94EclipseGST]

I think the FIAV holds the key to most idle problems. Once I replaced mine, idle steadied like a rock.

First thing that started to happen with the idle is it would begin to fluctuate within a couple hundred RPM. That lasted a couple of months, then the idle started staying high, like at around 1200 RPM. That lasted a month or so, then the car would not start when it was cold. The idle would drop unless I held the pedal down and warmed the car up. Then it would idle too high. If I adjusted the BISS to lower the RPM, then the car would die out sometimes between shifts, and when I started the car again in the cold, it would keep dying.

Change thed FIAV, because it was the last thing I didn't do, and I didn't want to block it off because the weather is getting colder in Illinois. After replacing the FIAV, I knew it worked the moment I started the car in cold weather and it idled at 1200 RPM, and slowly dropped to 750 as the car warmed up. Beautiful. It was probably the best $140 I spent on this car (well, that and the cost of new lifters because I couldn't stand hearing that mother tick anymore)!

You could block the FIAV to see if that clears up your problem, then you can replace the FIAV if you live in cold weather territory.

 

[tim_korn_99]

I think the FIAV holds the key to most idle problems. Once I replaced mine, idle steadied like a rock.

First thing that started to happen with the idle is it would begin to fluctuate within a couple hundred RPM. That lasted a couple of months, then the idle started staying high, like at around 1200 RPM. That lasted a month or so, then the car would not start when it was cold. The idle would drop unless I held the pedal down and warmed the car up. Then it would idle too high. If I adjusted the BISS to lower the RPM, then the car would die out sometimes between shifts, and when I started the car again in the cold, it would keep dying.

Change thed FIAV, because it was the last thing I didn't do, and I didn't want to block it off because the weather is getting colder in Illinois. After replacing the FIAV, I knew it worked the moment I started the car in cold weather and it idled at 1200 RPM, and slowly dropped to 750 as the car warmed up. Beautiful. It was probably the best $140 I spent on this car (well, that and the cost of new lifters because I couldn't stand hearing that mother tick anymore)!

You could block the FIAV to see if that clears up your problem, then you can replace the FIAV if you live in cold weather territory.

You hit it right on the spot. I blocked off my FIAV with some JB Weld, and it idles just fine now. Problem solved.
Thanks
-Tim

 

[skizzo81]

what is the fiac and where is it? my idle is high tooo

 

[92AWDHX40]

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

 

[skizzo81]

wahoo it was my biss screw

 

[92AWDHX40]

There you go, glad you fixed it, it can leak if the oring is bad, or if its not adjusted, good.

 

[skizzo81]

mine seems to me super loose and easy to turn

 

[tips000]

it could be the seals in the throttle body as well, spray a little grease at them but make sure to clean up any that gets inside the tb. and its also a good idea to rtv the gaskets

 

[skizzo81]

so your saying to rebuild the tb?

 

[Gysgt Guy]

wahoo it was my biss screw

! I wish all my dsm problems were fixed as easy as turning a screwdriver haha