Q: Idle Fluctuation 1K ~ 1.5K
 

Normally my car idles at about 800 rpm. I changed the IC two weeks ago and ran the car without any problems, car still idled at 800 rpm. I had the tranny rebuilt and a ACT clutch installed. Now once warmed up the idle fluctuates between 1000 and 1500 rpm. What could it be? I visually checked the clutch switch. Its at least not sticking. Neutral switch, 1-2 switch? solenoid? fouled plugs? reset ECU?

Mods are in my sig.

I hate when when thing gets fixed an another goes! :mad:

i have been seeing a lot of threads like this.
do a search for bouncing idle, and you should get a few results.

i have the same problem, but mine happened after i re-installed my gauges. its weird that is happened right after that, because i dont think the two are linked.

do you only notice this idle problem when its cold? mine goes away once the car is warmed up. sorry i have no sure solution for you.

I did but on fluctuation... I'll trying bouncing idle. Thanks

Mine started acting like that after I installed ACT flywheel and clutch too.

actually there was this one guy on her who i talked to and he said that he fixed his problem by replacing the "clutch switch". i dont remember the name for that thing but its the small switch the depresses when you disengage the clutch. check that and make sure its depressing all of the way.

also there were a few people who said their problem went away once they went stand alone ecu... such as the apexi pfc.

Bad Karm7, have you resolved the issue? I just replaced the clutch I kept my original flywheel.

Encosiderate, Yeah it's the clutch switch. I checked it to see if it was sticking but no. It's release just fine. I'll check the the switches with a voltmeter... I'm also going to call the shop and have them run some diagnostics.

Victor

I haven't been ambitious (Translation: lazy) enough to get back into looking for the issue.

Does anyone know if fouled plugs could be the culprit? I'll check those too!

vacuum bounces between 18-20 or so while idle fluctuates

nevermind

vchacon,

does it go away when your car is warmed up? is it always there when you start up?

When I start cold the AWS kicks in to 2500. Throttle it a bit and it comes down to about 1100. The bouncing idle starts once it starts to warm up.

There are two clutch switches, one at the top (pedal out) and one at the bottom (pedal on the floor). The plastic switch will move but the unit could be dead. After I installed my PFC my car would die when I pushed the clutch in at low idle or on decel (cheap to replace). Also, consider your TPS as they go out of spec over time. It has a narrow and full range idle and WOT setting. It's easy to adjust but you need a voltage meter to check it. Another thought, and I'm not sure about the stock ECU, is that after I made some changes and did the idle learning my PFC still needed some time to fine tune itself and corrected my idle troubles over time. Good luck

check your vacuum lines, also check your electric connectors around the manifolds. try resetting your ecu and letting it idle for a good 30 minutes on its own. more likely that not its a vcuum problem which would probably be a vacuum line.

Thanks for the suggestions guys. I'm at work I still have to drive home... I'll check out some of this stuff then.

Victor

My recommendation as well. When they go out of spec they can cause minor to large idle fluctuations.

So, I drive home (60 Miles) and as I pulling into town my car suddenly has a normal idle. Now if throttle the car a bit or but a load on the car the RPMs slowly fall to 1000-1100 rpm and then after 10 sec or so down to 850 rpm .

Here's the kicker. Before when I had a full electrical load, lights, radio, and brakes I would get a voltage reading of 12.4-12.6v now I'm getting 13.4 and 13.5 when I'm running the car. ????? Did I magically get a new alternator????

Any Ideas?

I'll check the TPS and lower clutch switch tomorrow.

Thanks

Victor