Crazy Idle

[bucket_man]

Hey guys,
Ever since ive had the car its had this wierd idle problem.
when i start it, it will rev up to about 2000rpm then sometimes if i take off before i let it warm up a bit (sometimes if i dont even take off) it will start revving up and down by itself, usually it will rev up to 2000 then down to 1500 then back up, like a sine curve.
Just wondering wether i should be worried and fix it or just let it go.
thanks

[chainz]

Is it like this?

http://media.putfile.com/BadIdle

[Deadhead]

Hehe... I remember when my car did that chainz... Easy fix... but quite annoying

so answer his question already :P

[B16KILLA]

Is it like this?
http://media.putfile.com/BadIdle

My car is starting to do that alot . What is it?

[chainz]

Hehe... I remember when my car did that chainz... Easy fix... but quite annoying

so answer his question already :P

I wish I knew - the video is from my car. Can you help me out Deadhead... or anybody?

[B16KILLA]

I went and got an idle air control valve , but I havent had a chance to put it on yet if it works i'll let you know

[Hondaisok]

Chainz: Your link is trying to put adware on my pc. Anyone else have this problem?

[chainz]

Chainz: Your link is trying to put adware on my pc. Anyone else have this problem?

Shouldn't be - its just a windows media file on my PutFile account.

Did you accidentally click on any of PutFiles advertiser links?

[B16KILLA]

Chainz: Your link is trying to put adware on my pc. Anyone else have this problem?

no

[Hondaisok]

No, I just clicked on your link and Norton trapped it.

[Hondaisok]

Tried it again and it killed Firefox. I'll scan my system-it may be something on it.

[halxi]

worked fine for me on firefox, with multiple virus protection programs going around.

Mine was doing that, i tightened up the fast idle control valve screw, its on the top rear of your intake mani, then i adjusted my idle to idle lower.

It only happens to me when its really cold out (35 or below)

[wprocomp]

mine was the EGR valve, if you press the diaphragm from underneath the EGR it will usually stop until you let go-go get one from the junkyard or pay like hell for a new one,wait does your car even have an EGR?

[chainz]

mine was the EGR valve, if you press the diaphragm from underneath the EGR it will usually stop until you let go-go get one from the junkyard or pay like hell for a new one,wait does your car even have an EGR?

Yes this is on my 89 Lxi - my junker 88 LX has too many idle problems to even bother typing about.

Also a heads up - I just aquired a 88 LXi coupe (w/ 5spd ) which I plan on swapping tranny into my LXi sedan. So since I will soon have three 3geezs I will be parting out my 88 LX sedan - I will put up a new thread when I do so.

[chainz]

OK Deadhead filled me in and said to try the following... but unfortunately this was not my problem - idle is still goin crazy.

Thanks for the help though Deadhead.

"Haha. ok, this took me forever to figure out, so be thankfull. j/k lol

but on the rear side of the TB there is your Fast idle control valve. It's got a cover on the top of it held on with 2 screws. Take the cover off and you should hear rushing air. Put your finger in the center part of the black thingy in there, if your idle steady's out, then that's your problem.

Take then a large flat head screw driver and turn that outer "ring" down until it's "snug"

That should fix your problem, just put the cap back on and your set. I did this when I had my accord and drove it for a good 10k miles before I traded it in, and it never gave me anymore problems."

[Deadhead]

Did the idle change though when you put your finger in it?

[chainz]

Did the idle change though when you put your finger in it?

No there was air whoosing through there - but there was no change when i blocked it with my finger - the idle still loped up and down.

[shepherd79]

well, if your ECU doesn't give you any codes for EGR, than you should adjust Fast Idle Valve.
It is easy to do. Remove the cover from the top of it (2 screws). start that car. get wide flat screw driver and turn it clockwise untill the idle levels. put everything back and you are done.
you may have to adjust regular idle after the car will fully warm up.

[bigal004321]

wow this is just what my car is doing.... but i am getting the egr code... where exactly is the egr and how do i check it.. i looked in the haynes manual but that was not helpful at all

[oldschool3g]

my car is kinda doing the same thing when i start it up cold in the morning it runs fine and feels fine...but it takes a long time to actually warm up to normal tempeture...and when it finally does..it starts vibrating..and jurking..not that much though...when it vibrates like crazy is when im stoped at a red light...its making me mad....can you guys help?

[Kabuki]

Jeez, guys... You have to make sure that the coolant supply lines to the fast idle valve are clear before you go tightening it down. This problem is actually a result of a vacuum leak, somewhere. The Fast idle valve can cause the problem for various reasons. Low coolant level or plugged supply lines will cause even a good FITV to malfunction. A dirty throttlebody can keep the blade sticking open a little. A broken vacuum hose or leak in the intake manifold gasket can cause this too.

[maxsideburn]

Kabuki is right. When I first changed my thermostat and refilled my radiator my car was doing this. Just disconnect your battery for a few minutes, make sure you have plenty of coolant, then when you reconnect the battery and start the car up it will have a chance to "re-learn" how to run properly.

Any FI car does this. In fact it's a good idea to "reset" your ECU fairly often, especially after doing any kind of work which could change the way your car runs.

[chainz]

ok I have thoroughly checked out the coolant (filled it 100% including bleeding the motor), reset the ECU, and tried the 'thumb in the valve' technique. Still no resolve to my problem.
I bought a vacuum pump tester tonight and found when I put vacuum on the EGR valve while idling (loping idle as always) the RPM smooths out and drops and the engine runs like ass. From what I know this means the EGR valve is good.
Any more ideas?

[chainz]

PS i am not getting a CEL and I checked the ECU and I am not showing any codes

[Deadhead]

have you checked for vacuum leaks? take some carb cleaner to all of your gaskets and hoses on your intake manifold. If your idle changes when you spray in a specific area, then you know you have a leak there.