Advance1

QUESTION AT BOTTOM


so as the title said

earlier today i decided to try to fix the vibration caused during idle (sometimes slight but as rpms drop even more the vibrations get more drastic).
current situation

model: AP1
year: 2002
miles: 109k
oil changed: within past 1k miles
oil used: Castrol GTX high mileage 10-30
filter used: Mobile 1
air filter: changed 5k miles ago
valve adjustment: done 5k miles ago
coolant fluid: flushed and changed with Honda Type 2 Fluid 5k miles ago
modifications: only t1r dual exhaust

today i did a map whack and cleaned out my IAC

procedure:
Map sensor

unplugged battery
disconnected the map sensor
whacked on the plug outlet to clear out any debris
sprayed with compressed air to clean out any debris
plugged back sensor
ensured there was a good connection
zip tied it around the plug horizontally and vertically

IAC
unplugged the sensor
unscrewed bolts
tilted over the IAC to get a good view
sprayed carb cleaned into the IAC liberally
(unfortunately i was not able to get out all of the black build up) the canal on the side looked cleaned but in the middle chamber there was still some black markings along the side walls, i was afraid of using a Q-tip or brush because it might of left some bristles in there causing more troubles
reinstalled IAC with a thin layer of oil
reconnected the sensor

Reconnected the battery
let it idle for about 15 minutes
took it for a drive and NEVER COASTED only downshifted through all the gears until 2nd where i preceded to wait till 1k before i clutched in and braked completely.


my question is
the owners manual for a AP1 states that the idle speed should be at 800 +- 50 rpm. by assuming that being the 4th thin line above 0 and that the next line on the RPM scale would be 1000 where it would be the thicker line. my car seems to always idle at one line below the fat line but there is still a hint of vibration. When the car idles at 1000 rpm the thicker fat line there is zero vibration and usually when coming to a stop the RPM hovers at 1000 rpm then after 30-45 seconds it will dip down to one line below (assuming that is 800 +-50) where it would then proceed to give off a slight vibration...


is this normal. do i need to actually consider replacing my Map sensor or IAC to get rid of the vibration completely
ive driven about 40 miles so far in a matter of 4 trips after my ECU reset and i was wondering after a longer period of time will the ECU become more adapted to the 800 rpm or 1000 rpm and vibrate less

any advice is helpful.. thanks!

SgtB

I wouldn't worry too much about the exact rpm as long as it sounds healthy and is stable. Does it still idle that high after it's warmed up all the way? It's normal for a cold start to idle high.

Reckon

I think a little vibration is common. I don't think your car should hover at 1000rpms for 30-45 seconds before dropping to 800 +/-, but I don't think that is a big issue as your ECU might still be learning.

Advance1

Yeah it just seems strange that for 0 vibration its at 1000 but once it gets to 800 where the manual says to be idle then it begins to vibrate

Reckon

Mine vibrates a little at that idle rpm as well. I thought I read on here a long while ago that since it's a high revving motor that the vibration at low rpms is common. The vibration should not be much nor should it be violent. You may want to double check your motor mounts to make sure there is no issue there.

speakeasy2009

My idle has been horrific lately. i find that when i first start the car it idels high which makes sense because the electronic choke is goin. But lets say i drive tio work and park the car, then a few minutes later go start the car again the idle is so rough and there are like 3 bars on the tach. i have to give it gas to get it going. Thats not normal.

I just tried seafoam in the gas tank and i felt a huge difference in how responsive the engine is so my idle issue, like yours, may be due to some other factors because the idle problem still exists. I cant do MAP whack because the bolt to get my MAP off is stripped but im going to try to clean the IAC as soon as the weather here in NY permits me to work on the car. Im also going to use seafoam on the vacuum lines to see if that helps.

Nothing bugs me more than idle issues..

s2cho

properly reset your ecu by pulling the fuse under the steering wheel. once you start the car you MUST hold the rpms at 3k until warmed up.

Advance1

http://forums.s2kca.com/showthread.php?t=27347

read this article, gassing it is the last thing you should do lol. my car shows on a regular day shows 4 bars on the tach but on a cold morning even after it is fully warmed up it drops down from 3-4 and hovers between them. for an ap1 the manual says that idle speeds are 800 +- 50, so when i was watching it this morning i was assuming that 4 bars was 800 and that each time it dipped to 3 bars it was still only within 50 of 800 so roughly 750... but then again a tach is just a guideline its not like it can accurately count how fast your engine is moving from 0 -9000.

but regardless of all that the car does vibrate more during 3 bars rather than 4. and does not vibrate at all once it hits 1k. when i was letting it idle this morning i noticed after it was from 3-4 bars when the fans kicked in it would jump to 1000 and there would be no more vibration. but after the fans shut off it dipped to 3-4 bars again.

rob-2

sounds fine to me. as long as the re-learn allowed for two fan cycles and your other items (lights radio etc) were off.

While the tac will show ~1K a obd scanner will show it around 850 or so. That's what mine showed.

The motor is 'rough' and doesn't have a silky smooth idle.