Cam Experts Please ,,, Question about Idle?
Thread Starter
Launching!
Joined: Oct 2002
Posts: 205
Likes: 0
From: PLano, TX
Cam Experts Please ,,, Question about Idle? i am trying to learn and i did try a search but no luck... i am going to try to define what happens and how i can correct it and please tell me if i am wrong or something i am missing:
A4 Camaro LS1
Comp Cam 222/226 .566 .569 12 lsa
the stock idle is like around 700 or so rpms and thats the absolute lowest the computer tells the engine to idle to at all times and the computer makes corrections to idle at that speed
so with an after market cam, the intake/exhaust is different now, the stock idle speed is not enough for it and it surges and dies after the air and exhaust is compleltly out of the engine
so to correct this, the idle speed must be high enough for the cam, like 900-1000 or so becuase thats what the cam needs to run good and not die
i did a test, and i put my foot on the brake and another on the gas very slightly and got the rpms to about 900-1000 and it ran great
and if i change the idle to 900-1000, the car will automaticly make adjustments with fuel and air to idle at the speed? becuase the computer is telling it to do so
please correct me if i am wrong and if theres something i am missing, again, i am trying to learn, i just got my cam on monday <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
thank you for all your help
A4 Camaro LS1
Comp Cam 222/226 .566 .569 12 lsa
the stock idle is like around 700 or so rpms and thats the absolute lowest the computer tells the engine to idle to at all times and the computer makes corrections to idle at that speed
so with an after market cam, the intake/exhaust is different now, the stock idle speed is not enough for it and it surges and dies after the air and exhaust is compleltly out of the engine
so to correct this, the idle speed must be high enough for the cam, like 900-1000 or so becuase thats what the cam needs to run good and not die
i did a test, and i put my foot on the brake and another on the gas very slightly and got the rpms to about 900-1000 and it ran great
and if i change the idle to 900-1000, the car will automaticly make adjustments with fuel and air to idle at the speed? becuase the computer is telling it to do so
please correct me if i am wrong and if theres something i am missing, again, i am trying to learn, i just got my cam on monday <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
thank you for all your help
TECH Fanatic
Joined: Nov 2001
Posts: 1,975
Likes: 2
From: SW Florida
Re: Cam Experts Please ,,, Question about Idle? Don't let anyone tell you that a cam in the duration of 220-222 will idle properly in an A4 car with NO PCM programming.
I installed a TR220 cam, TEA 5.3L heads, FLP headers, and an LS6 intake. The car runs like a monkey on fire, but will not idle in Drive.
Sent the PCM to Geoff at Thunder Racing, and now it idles [very] close to what is was when bone stock. Not only did Thunder increase the idle speed, they also increased the idle timing. Idle timing is the real fix to the poor idle these A4 cars have after a cam change. Also, these cams will cause misfire detection codes. And those codes will cause intermittent transmission converter lockup problems (at least with my Yank converter). Now.... No lockup problems at all... Fini, Finished, Goodbye
This thing is going on the dyno with a wide band very shortly. If I need to change the fueling, the PCM goes back to Thunder.
Mail order tuning is not as good as Dyno tuning, but I have fixed the following:
1. Fix surging and poor idle in Drive
2. Delete Torque Management
2. Delete EGR code
3. Delete AIR code
4. Delete Speed Limiter
5. Delete rear O2 Sensor Code
6. Set shift speed to 6,200
7. Set Rev Limiter to 6,500
8. Adjust Misfire Detection circuit
9. Lower Fan turn-on temp
I'm happy... Again, now it goes on the rollers and additional PCM tweeks if needed
Ron,
_________________________________________________
<small>[ March 18, 2003, 09:10 PM: Message edited by: Kimchee and Rice ]</small>
I installed a TR220 cam, TEA 5.3L heads, FLP headers, and an LS6 intake. The car runs like a monkey on fire, but will not idle in Drive.
Sent the PCM to Geoff at Thunder Racing, and now it idles [very] close to what is was when bone stock. Not only did Thunder increase the idle speed, they also increased the idle timing. Idle timing is the real fix to the poor idle these A4 cars have after a cam change. Also, these cams will cause misfire detection codes. And those codes will cause intermittent transmission converter lockup problems (at least with my Yank converter). Now.... No lockup problems at all... Fini, Finished, Goodbye
This thing is going on the dyno with a wide band very shortly. If I need to change the fueling, the PCM goes back to Thunder.
Mail order tuning is not as good as Dyno tuning, but I have fixed the following:
1. Fix surging and poor idle in Drive
2. Delete Torque Management
2. Delete EGR code
3. Delete AIR code
4. Delete Speed Limiter
5. Delete rear O2 Sensor Code
6. Set shift speed to 6,200
7. Set Rev Limiter to 6,500
8. Adjust Misfire Detection circuit
9. Lower Fan turn-on temp
I'm happy... Again, now it goes on the rollers and additional PCM tweeks if needed
Ron,
_________________________________________________
<small>[ March 18, 2003, 09:10 PM: Message edited by: Kimchee and Rice ]</small>
Re: Cam Experts Please ,,, Question about Idle? I run the ASA Hotcam with a stock stall on an A4 with no tuning using only a few tweaks and I can sit in traffic all day with no problems.
TECH Fanatic
Joined: Nov 2001
Posts: 1,975
Likes: 2
From: SW Florida
Re: Cam Experts Please ,,, Question about Idle? Hawk.....
That absolutly amazes me. How much did you have to drill out the TB hole? I drilled mine just slightly, but it doid not help that much. I was scared to drill the hole too much and wind up with IAC counts of zero.
That absolutly amazes me. How much did you have to drill out the TB hole? I drilled mine just slightly, but it doid not help that much. I was scared to drill the hole too much and wind up with IAC counts of zero.
