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.

 

[Pwrtrip75]

plugs and wires wouldnt have anything to do w/ it. Sounds like you knocked a vacuum line off somewhere. That will idle high and could explain the hissing sound you hear when you shut it off. Will also cause it to run like $hit because its running a lit leaner.

 

[Rsawd95dsm]

time for a boost leak test!

 

[LOLVTEC]

im in the same boat, my has idle surge cause i know i have a vacuum leak somewhere. i can hear it and feel air coming somewhere near my egr, evap canister around that area.
what you can do is try adjusting your BISS screw and see if that helps.
but definitely you have a vacuum leak somewhere

 

[talonandeclipse]

A boost leak test! also check your throttle cables they might not have enough slack so it's causing the high idle.

 

[Lofty]

Do a boost leak test, as the hissing noise should have tipped you off if you didn't need hand holding that there was an air leak somewhere causing the problem.

Visually check the vac lines first, it might be something obvious, also check your throttle cable and make sure it is not too tight. I would also recommend testing your idle speed controller. Links how to do it here.

http://dmtalon.v8eaters.com/ISC.html
Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)
Idle Surge FAQ

Here is how to make a boost leak tester.
IC Pipe Tester

Make sure you aren't venting your BOV, as that will cause issues as well.

Hope you get it figured out.

--Scott

 

[dsm nuff said]

Ok turns out the hissing was actually steam from a coolant leak. Theres a hose that connects into my oil filter housing? I dont know exactly what its called off hand but Im assuming its for cooling the oil. Anyway I noticed it was overheating and I dumped some water in and next thing I know my foot was getting wet. Its squirting out of this line. So that takes care of the hissing and overheating. I replaced all the hoses to my side mount becuase I thought I had a boost leak and that didnt fix it, so where else could I have a boost leak? As far as vacuum leak the kid I bought the car from has all the vacuum hoses all messed up ### he did a half ass emissions delete and and had a MBC hooked up so I removed that. Can someone post a pic of where all the vacuum hoses should be connected? I dont want a diagram because its just easier for me to look at pictures and copy them than it is for me to mess with a diagram. Im currently letting the car cool down so I can do a vacuum leak test with carb cleaner. I also unplugged the Throttle Body Positioning Sensor and started the car and still idling at 3000RPM. On top of the throttle boddy there is 2 vacuum lines that are just connected to eachother. They are labeled E and A2 on the throttle body itself.

 

[NOSLO2PT0]

Could also be the idle stop screw is adjusted in too far.

 

[MotorHead265]

I would do a boost leak check. Do you have a wideband? If so you should be running on the leaner side.

 

[Abe'sGST]

have you checked to see if your idle air control valve is working properly?, if it is do a boost leak test and check for any loose vacuum lines

 

[dsm nuff said]

How do I check my idle air control valve and where is it located? I did a vacuum leak test and my engine sped up when I sprayed behind the throttle body. Any suggestions? I know its on all the way because I checked and all the bolts are tight unless its the gasket which I didnt notice anything wrong with the gasket. As far as boost leak, like I said I replace the intercooler hoses and that didnt help so if it was a boost leak where else could it possibly come from?

 

[Abe'sGST]

im not sure on the 4g63, but its somewhere by the throttle body and intake manifold...im saying it could be that because back when i had my n/t it was doing the same thing and it was the idle air control valve, put a new one and fixed it right up

 

[92AWDHX40]

Boost leaks can come from anywhere so many places check it out.

 

[Lofty]

http://www.youtube.com/watch?v=KibYz21IMA0&feature=player_embedded

 

[dsm nuff said]

Thanks! Ill pull my ISC off tomorro first thing and give it a test.

 

[Sawboo]

Maybe you should try a boost leak test... That should be pretty helpful for finding a leak.

 

[dsm nuff said]

Anyone have an easy way of doing a boost leak test? I have limited resources right now so I cant buy anything untill I get paid. And I might need the ISC and thats 130 bucks. So I need a really cheap way to do a boost leak test.

 

[92AWDHX40]

Cheap way cheap part. Lowes DIY

 

[1gAWT]

Check the idle idle speed control screw (ISC) on the throttle body, it ###### came lose and needs retightened otherwise vacuum leak as mentioned.

 

[Abe'sGST]

Check the idle idle speed control screw (ISC) on the throttle body, it ###### came lose and needs retightened otherwise vacuum leak as mentioned.

like the video posted above said, if you are having idle problems and you go and adjust the BISS you probably made a mistake, idk why people go straight to it instead of looking for and fixing the real problem

 

[dsm nuff said]

Ok so I pulled my ISC off today and it checked out. Read 28.5 across the board. So thats not the problem. It had a good amount of carbon build up though. Anyways I think I might have found my problem. I know I have a boost leak and I will be testing it on monday to locate it. I was gonna check the O-Ring on my BISS screw and first noticed there was Blue RTV Silicon all over the whole. Which tells me that the kid I bought it from must have known something was up with it and that was how he tried fixing it. So I cleaned that off and tried taking the screw out to check it out and I couldnt get the screw out. It wouldnt back out far enough for me to grab it with anything. Do I need to remove my throttle body to get it out? Or should it come all the way out just by unscrewing it? If its supposed to come out by unscrewing it then I think the kid might have put a wrong screw in there or something because it comes just to the top of the whole and no further.

 

[cliffkemp]

Ok so I pulled my ISC off today and it checked out. Read 28.5 across the board. So thats not the problem. It had a good amount of carbon build up though. Anyways I think I might have found my problem. I know I have a boost leak and I will be testing it on monday to locate it. I was gonna check the O-Ring on my BISS screw and first noticed there was Blue RTV Silicon all over the whole. Which tells me that the kid I bought it from must have known something was up with it and that was how he tried fixing it. So I cleaned that off and tried taking the screw out to check it out and I couldnt get the screw out. It wouldnt back out far enough for me to grab it with anything. Do I need to remove my throttle body to get it out? Or should it come all the way out just by unscrewing it? If its supposed to come out by unscrewing it then I think the kid might have put a wrong screw in there or something because it comes just to the top of the whole and no further.

It can come out...Not sure if it is magnetic or not either...try that. If you sprayed on the TB and the engine went up in rpms, you may need to replace the tb seals.... Seeing how the BISS screw hole is not functioning properly, try to screw it down most of the way and just put you finger over the opening...If this is the main problem, the idle should go down as it will not suck any air down at that place. IF this is not the only leak, it may affect your idle some but, will go back up if not the main issue....

For the idle to be high, usually have a leak at or after the TB....Intake manifold may have a hose that came off/broke so, check it as well. Cannot think of anything else off hand....boost leak is not going to mess with your idle unless it is the tb itself or after it....you are getting air in after it is closed, to up the idle.

 

[dsm nuff said]

I will try that tomorrow. The reason I know I have a boost leak as well is becuase when I hit 8psi it studders really really bad. There has to be a huge boost leak somewhere. Only thing is I cant figure it out so Im gonna do a boost leak test. I tried a magnetic screwdriver for the BISS screw and it wouldnt pull if out. Maybe I will try a big magnet or something. This car is giving me a damn headache!

 

[cliffkemp]

the threads are pretty fine so may take several turns...did you try to screw it in all the way and see if your idle changes/goes down or reacts to it in any way...if it does, this may be a significant part of the problem although not all the problem....you may have a leak at the manifold at the head as well....I still believe you have a leak at the tb and it is compounded by the biss problem as well. screw in the biss screw, if the threads are good, and listen to the idle change, if any....If i does not change at all, you have a major problem elsewhere. IF you screw it in relatively fast before it gets tight, the rpms should drop a significant amount if this is a major part of the problem. To be idling that high, you have a major leak at the TB/intake manifold so check the underside of the manifold and check the hoses that go to and from the tb to see if they are plugged in to where they go and not just the TB....

Try some tweezers if you can to get the screw out after you have screwed it down first, then back out as far as it will go...while it is down...try to dig out some of the rtv crap out of the hole...it may just be a small amount on the bottom of the screw that is attatched and holding it in and you will need to keep 'unscrewing' it to break off that part of the rtv stuff... either way, at least you will know the extent of the biss affecting your idle. If I were there, would show you and help you with it.

 

[eligst21]

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.

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.