1G Car Idles at 3000RPM

[dsm nuff said]

So I got my talon back on the road today after fixing the gas leak for about a week. Its now idling at 3000RPMs. It used to idle high about 1500 -2000 but now its at 3k. Anyone know what might be causing this. I can almost guarantee I need plugs and wires but idk if that would cause this high of an idle. Also when I turn the car off I can here a hissing sound. Not my tires ### its coming from the engine bay towards the front around the exhaust manifold and the turbo. The engine is studdering really bad as well.... Its running like complete a** right now. Ill try and post a video of me driving and how its running if it will help just gotta find a video camera.

 

[cliffkemp]

Have you addressed this problem yet? Sounds like its a pre turbo exhaust leak maybe. I would definitely look and see where the leak is exactly coming from. Also, you should not be touching the biss screw even if it looked like it was messed with. Now you need to go and address and adjust your biss to where it is suppsoed to be. If not, then you'll burn you isc and then you need another.

Also where were you getting a isc motor for $130? They are cheap at a junkyard, like jafro did in his video.

he said the hissing noise was from the coolant getting too hot....if i read an earlier post correctly....it is ok to turn the biss screw while running just to see if the idle will go down as it is tightened down as it should lower the idle as it becomes tighter (not all the way in though).

If he does tighten the biss until it is all the way in, it should make the idle go down in the process unless it is stripped or, that is not the main leak....

My thought is, the idle being as high as it is means that there is a leak but, it is at or after the TB...a simple boost leak before the TB is not going to change the idle but, will make idle rich as it is unmetered air. He has a major leak at the TB or the TB butterfly is stuck (too much tension on the cable or something else keeping it from returning to normal and could be the idle control (electrical) or he has something off like a vacuum hose on the intake manifold or a leak somewhere on the manifold that is letting air in after the TB causing a high idle....

he said he had a lot of rtv in the biss hole....he is wanting to get it out to check it but cannot...if the idle is the result of the biss, he can check easily by tightening it quickly and see if idle changes....if idle does not change, while tight, he can scrape out some of the rtv...playing with the biss all the time will hurt the motor if it is always adjusting....it could be the problem as well but, to eliminate the biss itself, that is simple to find out.

 

[dsm nuff said]

Earlier today I put my finger over the BISS screw hole and the idle dropped slightly. Then I turned the BISS all the way in and it dropped a little more. Now I just went out and did a cold start. The car idled at 3k for a few seconds then droped down to 500 and felt like it was going to stall. Then suddenly it went up to 2k and then dropped to 1500. After that it just keep surging between 1k and 2k. Also the needle on the stock boost guage jumped around a bit. Wasnt alot though. I saw a video on youtube with a 1g doing the same thing only it didnt idle at 3k at first startup. Mine hasnt stalled out yet but it feels like it wants to.

 

[cliffkemp]

Earlier today I put my finger over the BISS screw hole and the idle dropped slightly. Then I turned the BISS all the way in and it dropped a little more. Now I just went out and did a cold start. The car idled at 3k for a few seconds then droped down to 500 and felt like it was going to stall. Then suddenly it went up to 2k and then dropped to 1500. After that it just keep surging between 1k and 2k. Also the needle on the stock boost guage jumped around a bit. Wasnt alot though. I saw a video on youtube with a 1g doing the same thing only it didnt idle at 3k at first startup. Mine hasnt stalled out yet but it feels like it wants to.

Sounds like you have 2 issues....since the idle dropped to almost stall, the biss is part of the issue with the leak but, at least you know the threads are good and may just be a damaged seal as it has a seal on it too...

The other issue is the TB which could be 4 things now....worst case is the computer trying to go out on you either from heat damage or caps leaking if it has that issue...

a leak in the manifold somewhere that is not easily seen
TB is leaking at the seals as it has 2 and the back seal where it mounts to the intake
lastly, it could be an issue with something electrical that is compounded...
example, a leak with idle control issues as well as temp sensor can cause a high, irratic idle....

Only thing to do now is, get the biss out and check the seal, check your computer for caps damage, check the idle control, and check the coolant temp sensor as it works together with the computer to control the idle. It really sounds like an electrical issue with the idle control, coolant temp sensor, and possibly the computer. you can spray the TB and if the idle picks up some, you have a leak at it as well.

you will have to fix all the leaks at/after the tb before you can fix the idle for good as it sounds like you have an electrical issue as well....

in other words, i believe you have a leak at/after the tb that is significant enough that the idle will go above what the computer is programmed to be normal so it is constantly trying to bring it down but the leak is too significant....

I had a loose biss and was open too far and did the same thing....fixed the biss and now it idles around 800 or so and steady. before the biss fix, it idled at 1500 til it got warm then, computer tried to bring it to 1000 but, went back and fourth between 1000 and 1500 when i pushed in the clutch.

boost gauge is going to move some as the engine nears stall, the computer will try to add a little fuel to get idle up and put a slight load on the engine causing your gauge to register around 0 on the stock gauge...that is normal....it wont build boost at an idle or even at full throttle other than maybe a lb or so as the engine is not under load when accelerating in neutral or with clutch engauged....

 

[dsm nuff said]

ok i will try and get the BISS out tomorrow. As far as throttle body goes do you think I should just get a new one? Also I hear of an oscilloscope? Will that tell me where all my issues are? There has to be some kind of tool that will just tell me every single problem my car has and where the problem is located right? I dont have a check engine light so OBD scan wont help. And where is the computer located? I was looking for it in my engine bay and couldnt find it unless I am just blind.

 

[cliffkemp]

ok i will try and get the BISS out tomorrow. As far as throttle body goes do you think I should just get a new one? Also I hear of an oscilloscope? Will that tell me where all my issues are? There has to be some kind of tool that will just tell me every single problem my car has and where the problem is located right? I dont have a check engine light so OBD scan wont help. And where is the computer located? I was looking for it in my engine bay and couldnt find it unless I am just blind.

You can repair the existing throttle body by taking it off and getting new seals for it. The oscilloscope may help find a leak but, just spraying, lightly, on the throttle body and on the intake side and seeing if the idle changes is, usually, just as good for finding leaks while the car is running. As long as the seals are good and the throttle body-to-manifold seal is good, a new throttle body is not needed unless the butterfly is damaged or not working properly and cannot be fixed which, is highly unlikely.

The computer is located behind the radio in the car. You will have to take apart the liner where the console meets the floorboard and it will be located about shin level behind where the radio wires are.

 

[dsm nuff said]

Oh ok ya I saw a box back there in my Eclipse but I didnt know what it was. What an inconvenient spot .

Ok now everytime I stop, the car stalls. This is getting really annoying. Im gonna go try and get the BISS out. If the O-ring is good then it has to be my throttle body.

I just spent the last hour and a half working on my throttle body. I pulled the throttle body off. I cleaned it nice and shiny with carb cleaner. I saw some residew on one of the gaskets so I think thats where the leak is coming from. I pulled the BISS out and put a new o-ring on it. There is a sensor that is right next to the throttle mechanism and Im assuming its supposed to touch the plate when the throttle is closed? It wasnt touching so I screwed it in a little so it does now. I put RTV gasket sealer on both the throttle body and the manifold to hopefully seal the leak temporarily untill I can get new gaskets. The butterfly was sticking a little so I made sure I got all the carbon build up cleaned out. It no longer sticks. I put it all back together and now Im just playing the waiting game to see if it sealed right. Gotta let it sit for an hour. Also I noticed a hose coming off of my thermostat housing that goes into the firewall is cracked pretty bad. Im guessing its for my heater? My heat was working excellent last time I used it which was a couple weeks ago. I havent tried using it since I noticed the crack for fear of leaking coolant everywhere. Anyone know what this hose is?

Ok that seemed to fix most of the problem. My idle isnt as high or crazy. Still have a tiny surge but not as bad. The car still has a boost leak somewhere else but im gonna have to test for it and see what I come up with. Probably could use a tune-up and some Lucas Fuel Injector Cleaner as well.

 

[codym]

I have this same problem, I cleaned out my throttle body and I have to say it had a lot of carbon build up. After putting it back together it will idle at around 3000, and if I tap the throttle it will go down to 1 and jump back up to around 3. I've double and tripled check all hosesand wires and such that I disconnected. I have the 420a non turbo, so there is no BISS screw to adjust on my throttle body( as far as I know) please help thank u

 

[dsm nuff said]

My idle is down to 1000rpms now and it surges a tiny tiny bit now all I am waiting on is the boost leak test. I cant get the stuff to make a tester yet untill my house arrest is over which is next week. After that I will getting out to home depot and getting the things for it.

 

[cliffkemp]

I have this same problem, I cleaned out my throttle body and I have to say it had a lot of carbon build up. After putting it back together it will idle at around 3000, and if I tap the throttle it will go down to 1 and jump back up to around 3. I've double and tripled check all hosesand wires and such that I disconnected. I have the 420a non turbo, so there is no BISS screw to adjust on my throttle body( as far as I know) please help thank u

You have bad leak. Sounds like you put a hose in the wrong place. Check you hoses. A high idle on a 420a is usually caused by missing a hose somewhere. You may have mis adjusted your throttle body as well. Check your pcv valve hose for cracks or leaks and the valve itself. Also, check your intake manifold for a missing hose attachment. Lastly, check the map sensor. If it is going bad, it can mess with your idle.