My car is idling at 950 RPM, is that right?
#21
TECH Enthusiast
iTrader: (3)
Join Date: Sep 2005
Location: NY
Posts: 635
Likes: 0
Received 0 Likes
on
0 Posts
GM sets the idle at 850 (according to techII) on my 02 TA. Since my TB is screwed up its been idleing at 960 (according to techII) and continues to set the high idle code (check engine light).
#22
I notice a higher Idle RPM (around 1000 RPMs) on my stock 98 Trans am A4. Assuming that my tach is accurate, what could cause the idle to be high? Is there anything I should change/fix?
#23
10 Second Club
iTrader: (28)
Originally Posted by BigBas83
I notice a higher Idle RPM (around 1000 RPMs) on my stock 98 Trans am A4. Assuming that my tach is accurate, what could cause the idle to be high? Is there anything I should change/fix?
The tach's on these cars are horribly inaccurate, but even more-so on 98's I've found. I've got my warm idle set at 700rpm and my tach reads 1000. My shift points are at 6400rpm but the tach needle will swing to ~7000rpm before it shifts. Don't rely on your tach.....from the factory, an a4 LS1 is set to idle at 550 in gear, 650 in gear w/ac on, and 650 in park/neutral ac on/off. Unless it's been tuned, that's what all a4 cars idle at regardless of what your tach says.
#25
Banned
iTrader: (7)
Join Date: Sep 2005
Location: PHX az
Posts: 112
Likes: 0
Received 0 Likes
on
0 Posts
my 98 has idled right above 1k, seems to be about 1050... and only 1 single time has it went below to about 850 for about a minute... not sure why it did that? but the 1k idling doesnt bother me, ill look into it when tuning time comes around.
#26
Launching!
Thread Starter
Join Date: Oct 2004
Location: Greenfield, IL
Posts: 226
Likes: 0
Received 0 Likes
on
0 Posts
HHHmmm wow there is a pretty big difference in what people have said. 500-1100???
But I went and rechecked it and its still at 950rpms, and thats after it settles down.
Are our tacks really that bad or just a difference between out cars?
Joel
But I went and rechecked it and its still at 950rpms, and thats after it settles down.
Are our tacks really that bad or just a difference between out cars?
Joel
#28
TECH Senior Member
iTrader: (21)
Originally Posted by ssmaro
HHHmmm wow there is a pretty big difference in what people have said. 500-1100???
But I went and rechecked it and its still at 950rpms, and thats after it settles down.
Are our tacks really that bad or just a difference between out cars?
Joel
But I went and rechecked it and its still at 950rpms, and thats after it settles down.
Are our tacks really that bad or just a difference between out cars?
Joel
#29
Banned
iTrader: (1)
Join Date: Apr 2006
Location: NJ
Posts: 373
Likes: 0
Received 0 Likes
on
0 Posts
According to my tach, my 98 M6 idles at about 1100RPM, fully warmed up.
So I guess thats more like 950 RPM, since smeone mentioned the '98 tachs are about 150 RPM's higher than what the actual idle is??
So I guess thats more like 950 RPM, since smeone mentioned the '98 tachs are about 150 RPM's higher than what the actual idle is??
#35
TECH Enthusiast
iTrader: (2)
Join Date: May 2004
Location: East Bay, Ca
Posts: 679
Likes: 0
Received 0 Likes
on
0 Posts
1100 for about 5-10 seconds on start up, quickly falling to 800-1000(in PARK)...and continuing to drop as operating temps rise...then settling at just over 500 when at operating temp(IN GEAR). A4, automatic. Obviously it idles the same when the ambient temperature is less, just taking longer between intervals.
#36
TECH Enthusiast
iTrader: (2)
Join Date: May 2004
Location: East Bay, Ca
Posts: 679
Likes: 0
Received 0 Likes
on
0 Posts
One other thing, just be clear if you're talking about cold start idle vs operating temp idle. Idle in park tends to be slightly higher...cold or warm.
And in cold climates start up idle is usually higher.
And in cold climates start up idle is usually higher.
#38
TECH Enthusiast
iTrader: (2)
Join Date: May 2004
Location: East Bay, Ca
Posts: 679
Likes: 0
Received 0 Likes
on
0 Posts
You have a lid and exhaust with a tune and idle at 1100? Who did that tune? How long ago was it done? Doesn't sound good.
Throwing any codes...SES light?
Is your IAT sensor connected?
Start there...
Throwing any codes...SES light?
Is your IAT sensor connected?
Start there...
#40
Moderator
Assuming nothing is wrong with your car, Idle is determined by a table of values within your PCM.
This may vary by year, engine package and transmission type, but here is my stock Idle Speed table (I have a 1998 A4).
(BTW, in my opinion, for our cars, at operating temperature, anything over 950 idle while in gear is really too high for my taste, even with a cam. I won't put a cam in my car that makes me idle it at 1100 RPMs. )
This may vary by year, engine package and transmission type, but here is my stock Idle Speed table (I have a 1998 A4).
(BTW, in my opinion, for our cars, at operating temperature, anything over 950 idle while in gear is really too high for my taste, even with a cam. I won't put a cam in my car that makes me idle it at 1100 RPMs. )
Code:
-40 -19 3 24 46 68 89 111 132 154 176 197 219 240 262 284 In Gear A/C Off 850 850 850 825 775 700 700 625 575 560 550 550 550 550 550 550 In gear A/C On 850 850 850 825 775 700 700 625 575 560 550 550 550 550 550 550 In Park A/C Off 1050 1050 1050 1020 960 865 865 775 710 695 650 650 650 650 650 650 In Park A/C On 1050 1050 1050 1020 960 865 865 775 710 695 650 650 650 650 650 650