99 Eclipse RS 104k

Idle speed sway slightly between 700 and 800 rpm after warming up.

Plugs and wires are new.
I cleaned the throttle body.
I also checked the resistance of coil pack and it's okay.
So, it does not look like misfire.

What could be the cause?

Thanks

seems pretty normal to me unless you have not explained it well enuff

yeah whats the problem?
a 100rpm sweep is not unstable.

maybe he means that it jumps 700-800 rpms?

I mean the idle sways between 700 and 800 rpm.
I don't know if it is normal because the idle speed of my another car (97 saturn) is very stable, the needle does not move at all.

I can feel shaking when the idle drops to 700.

that's perfectly normal for our cars.. 700-900 rpm is typical idle speed and it can easily vary 100-150 rpms. When the break is pressed at a stop it should go up to 1000-1100 for a while as well (for power breaks, etc, i believe).

thanks. :-)

That is not normal. There could be a number of possibilites, maybe your Idle Control Sensor/motor is going out.

Edit- maybe a slight sweep inbetween 700 and 800 RPM's is fine, but if it surge's between them alot, it's not normal. You even said the car felt like it starts to stumble when it goes down around 700 RPM.

Originally posted by 420a-Tnthewerks
That is not normal. There could be a number of possibilites, maybe your Idle Control Sensor/motor is going out.

it is normal for a car with 104K miles on it.
its all the gunk in the intake,small vacuum leaks from old vacuum lines,etc.. normal for 100K miles IMO

Originally posted by mcgyvr

Originally posted by 420a-Tnthewerks That is not normal. There could be a number of possibilites, maybe your Idle Control Sensor/motor is going out.

it is normal for a car with 104K miles on it. its all the gunk in the intake,small vacuum leaks from old vacuum lines,etc.. normal for 100K miles IMO

It's still not "normal". There's obviously something that can be fixed to stop it from doing it because they don't come like that from the factory. Both my DSM's never did with 100k+ miles(until recently the GST started have HUGE idle problems).

all he can really do is replace all the vacuum lines, gaskets,clean out the intake/iac motor,etc..
no car with 100K miles drives like it did when it came out of the factory anyways

mine does it too, as far as I can rememeber it always did it

yes the idle sway between 700 and 800 at an interval of a few seconds. I can feel shaking when the idle goes down to 700. Is this a symptom of bad IAC?

I cleaned the throttle body, IAC,
changed TB gasket,
replaced PCV, PCV tube,
the tube between intake duck and camcover,

So, what next?

vacuum hoses,egr parts, manifold gaskets,

I had a exhaust installed on my non-turbo and after that the idle started to change. MT- and in idle it will surge from sometimes 400-1200. I know its way off but not sure how to fix it. from everyone i talked to, i went ahead and installed a SAFC II and had the car dyno'd helped alittle but still off. Plus after the SAFC was installed the MAP sensor light came on.. Replaced and light still wont go out. Any ideas?

Originally posted by Pheonix_Racing
Plus after the SAFC was installed the MAP sensor light came on.. Replaced and light still wont go out. Any ideas?

The SAFC is probably causing that, seeing as it's hooked in line with the MAP.

ya bro its normal... i see em all day long here at stan..... no big thing as long as when u rev the car dont die! lol u can always raise the idle at the tb if it bugs u


02:19:18pm DarkOne> They'd have had to brought a whole fucking JUG of KY.
02:19:28pm InFiNiT3> lol no shit
02:19:39pm DarkOne> and a funnel.
02:19:45pm grain> have to get the ky with warming
02:20:00pm InFiNiT3> i feel sorry for the 18 y/o (one was 17 one 18) his name was plaster'd all over the news n news paper
02:20:06pm DarkOne> Yeah, has to be warming.
02:20:06pm BuckNutty> jus spit on it and it'll go in
02:20:17pm InFiNiT3> aye the ky w/ warming any good>
02:20:45pm grain> never tryed it
02:20:50pm grain> i applyed for a sample on thier website
02:20:56pm BuckNutty> evan didn't complain any
02:20:56pm BuckNutty> it felt nice
02:20:57pm InFiNiT3> lol
02:21:01pm grain> i use id glide whne she dries
02:21:06pm grain> good stuff
02:21:45pm InFiNiT3> thnx for the new sig guys
02:21:45pm DarkOne> Are we still talking about fucking dead chicks?

thanks, i checked it and it is definitely drawing power from the MAP so the sensor isnt getting enough power... Someone suggested using a diode to get the power back... What do you guys think...Or have you heard of any other fixes... Normally i wouldnt care, but have to get the car inspected before i go overseas and they wont pass it with the check engine light on...

its how you installed the safc and the setting you have it on.
you have it for pressure sensor and 7in/7out right.

while we are on this subject my car surges i believe the term is after driving for a while when i stop at a red light or push my clutch in my idle goes up to like 2200 rather than drop down below 1000 been doing this for a while now, cant seem to fix it replaced tps and checked hoses. any ideas???? thanx

ill check the 7in/7out tonight when i get off work... Im going to spend the weekend adjusting it anyways... I need to change the power band to lower rpm's, right now its huge about 4k, but in the city i never get much chance to use it.

did you have any benefit from the larger TB, ive been weighting the costs, so wanted to hear from someone that has one. Also about the high idle surge, my roomate bored his tb and it idled extremely high like that, then he got a new butterfly and it went away.

theres definatly a diferance with the bigger throttle body i can only speak for 55mm it works great, heard this was the best for our cars no higher dont know but as for the 55 theres a difference in throttle response and pick up. dont spend anymore the $50.00 on this project though. i believe concept illusions is still doing this they did mine.

One thing you might try is putting in Shell V-Spec gasoline, i've noticed that my car doesnt seem to like certain gas companys, such as arco, it idles really rough when i use cheap gas, and to clean it up, i used V-spec, and it worked fine after it got the cheap stuff out of its system. That could just be my car though, all 140,xxx miles on it. My sisters got a 95 AT and it idles between 200-300. feels shitty, but its never died on her. :shrug

checked the settings and it is set for 7 in/out... Then started adjusting the lo throttle and this solved alot of the problem... However i couldnt get a A/F gauge this weekend to tune it exactly, so im buying one today to get all the kinks out.

I here ya on the gas, when i first got the car i used exxon and my car would stall out for no reason, so know i pretty much use shell or amoco..