Stock idle speed

**IRACE2** · 11-07-2005, 08:35 AM

What is the stock idle speed on a 99 a4.

thanks

**SeVeReDiStOrTiOn** · 11-07-2005, 08:44 AM

400-500 rpms during closed loop....about 600-700 during open loop

**Sarge** · 11-07-2005, 08:46 AM

AC on in closed loop 800
AC off closed loop 600
open loop 700-800

**IRACE2** · 11-07-2005, 09:27 AM

Thanks guys

**SeVeReDiStOrTiOn** · 11-07-2005, 10:07 AM

600 closed loop..shit, my car must be broken...mine idles around 400. Then again I doubt the stock tach is very accurate...whats the best way to get a accurate reading?

**shady1504** · 11-07-2005, 06:03 PM

mine has always idled at 500, I once had an egr leak where it goes into the intake causing it to idle lower than 500 and felt like it was going to die.

BlackHawk T/A · 11-07-2005, 11:24 PM

500-600 here

Stock A4

**CDS98Z28** · 11-10-2005, 12:30 AM

i'm assuming that this is in drive btw and mine is at about 700/800 in drive w/out ac

**Redbull** · 11-10-2005, 08:23 PM

mine idles low, 400-500..but i think i need tunning after cam install. (02 zo6 cam)

sonnyred · 11-11-2005, 03:34 AM

Mine idles at 750

**SeVeReDiStOrTiOn** · 11-11-2005, 04:26 PM

Originally Posted by sonnyred

Mine idles at 750

that in park?

sonnyred · 11-11-2005, 04:47 PM

Originally Posted by SeVeReDiStOrTiOn

that in park?

Thats it 750 rpm. Completely stock except k@n filter.

sonnyred · 11-11-2005, 05:12 PM

Sorry foregot to say its a six speed.A4 may different.

**CDS98Z28** · 11-11-2005, 09:40 PM

790

**IRACE2** · 11-14-2005, 02:30 AM

Can someone explain what open and closed loop is.

**SeVeReDiStOrTiOn** · 11-14-2005, 08:35 AM

Originally Posted by IRACE2

Can someone explain what open and closed loop is.

Open loop is the condition your motor is in while it's running but is still cold. The thermostat is closed...motor idles a little faster to help warm up...the o2 sensors are bypassed by the pcm until it senses that the motor is ready.

Closed loop is the condition when the motor is warm....idle drops because all the sensors are telling the pcm that it's warm...the theromstat opens up...pcm uses the o2 sensors for fuel managment.

**2001NBMZ28** · 11-14-2005, 11:55 AM

I wrote down my stock closed loop idle speeds (A4) off my Predator before tuning. Tach was fairly close and steady, but the scanner showed it actually switching back and forth a little:

P/N - 645-676
In gear with foot on brake - 525-585

Might vary a little from year to year too - dunno for sure.

**CDS98Z28** · 11-14-2005, 06:50 PM

what i need to know is how do i set the correct throttleblade angle or basicly the idle screw setting... i have an aftermarket billet TB but there was no idle screw for it because i had to transfer the screw from the old one to the new one but now i don't know how to set it right because the IAC adjusts alot for the setting on there....i'm just wondering if you hook a voltage meter up the TP sensor and monitor voltage like you would for the idle stop mod...anyways the service manual doesn't say crap about it even for the stock setting....what is the stock closed throttle voltage at the TPS?

**CDS98Z28** · 11-14-2005, 07:07 PM

also here is the procedure for relearning the idle from the GM service manual:

AUTOMATIC TRANS:
ign. off
remove pcm batt fuse
wait 5 min
replace pcm batt fuse
a/c off
park brake and block drive wheels(do not use brake)
start vehicle
allow coolant to reach over 176F
shift into drive
wait 5 mins
turn on a/c
wait 5 mins
shift to park
wait 5 mins
turn off a/c
wait 5 mins
turn off engine. off

MANUAL TRANS :

ign. off
remove pcm batt fuse
wait 5 min
replace pcm batt fuse
a/c off
park brake and block drive wheels(do not use brake) PUT VEHICLE IN NEUTRAL
start vehicle
allow coolant to reach over 176F
turn on a/c
wait 5 mins
turn off a/c
wait 5 mins
turn off engine for 30 secs

this should help with many idles

then a relearn driveability cycle should be done http://www.obdii.com/drivecycle.html

**Fedge** · 02-25-2006, 08:44 PM

hope that works...mine has been a steady 1010(approximate) open and closed loop since I got it...no SES, well I did manage to kick it off when I when racing today a couple of times, but then it went away...