Nailed that Idle

[timothydog]

After about 30 minutes or so I finally got my IAC down to 17 in park/ 27 in gear. TPS .42-4.5. Besides idling great, I was suprised at how big a difference it made in overall driving.

Just thought I'd spread the joy.

Peace.

 

[ChrisF]

What was the procedure you used for achieving this?

 

[timothydog]

Well, you're going to need a scan tool of some sort. Obviously.
Turn the car on and let it warm up for a few minutes.

Observe your IAC #'s in park at idle (closed loop).
You wanna get them in the range of 10-20.
Most likely your counts will be higher.

You want to turn the set screw clockwise (to lower the IAC) only about 1/4 turn at a time allowing a little time for the idle to settle.

As you adjust the set screw, switch to your TPS and make sure it is in the .40-.46 range. If it isn't, you want to stop the car and set it there. When the TPS is set go back to adjusting the set screw. Eventually you are going to get the IAC #'s down where you want them. At this time, you want to shut the car off and adjust the TPS one last time.

After that, you are all set!

 

[TurboDave]

Originally posted by timothydog
After about 30 minutes or so I finally got my IAC down to 17 in park/ 27 in gear. TPS .42-4.5. Besides idling great, I was suprised at how big a difference it made in overall driving.

Just thought I'd spread the joy.

Peace.

Amazing how such seemingly simple adjustments can make such a huge differnce aint it?

 

[FlyinGN]

it makes a big difference don't it?? Its amazing..

 

[Danster]

Question, does adjusting the cam sensor while the car is running help any? I thought I read in a thread somewhere people were doing this and had a better idle.

Dannyo

 

[Rick]

Getting ready to do this today to a buddies car that keeps dieing at idle. Where exactly is the set screw?

 

[dpok69]

Its by the throttle bracket where all the cables are attached , it may have a cover on it. It is in the back side. If i recall, the screw also has a spring on it.

 

[TurboDave]

Originally posted by Rick
Getting ready to do this today to a buddies car that keeps dieing at idle. Where exactly is the set screw?

Having a scan tool that displays IAC and TPS will ensure the job gets done right.

 

[Rick]

What gives? The TPS is at .42 and the IAC count is #100.

 

[timothydog]

Your IAC's are too high like mine were.
Turn the throttle screw clockwise 1/4 turn at at time and watch the TPS numbers as you go.

 

[TurboDave]

Originally posted by Rick
What gives? The TPS is at .42 and the IAC count is #100.

Unfortunately, you suffer the same mallady that I'd bet over 75% of all Turbo Regal owners do, particualarly if you're NOT the original owner. Someone, somewhere along the line has jacked the minimum air bleed screw around (thinking that it's an idle rpm adjuster) trying to fiddle with the idle rpm. Hell, I've even seen mechanics twisting on that screw trying to get the idle rpm where they want it.

I'll go out on a limb here and say this; If anybody out there IS NOT the original owner of the T/R they're driving, chances are better than 90% that the IAC and TPS are out of whack (unless you have a scan tool and know how to fix it).

 

[Rick]

I'll do it this weekend. Thanks for the info. Need to check mine too now.

 

[wiked87gn]

hehehehe just got mine set.

at idle it went down and stayed at 15, in drive stayed at 22, with my TPS showing .46, man what a difference, i cant even feel the engine running.

 

[timothydog]

My sentiments exactly.

 

[TurboJim]

Use IAC counts ONLY if you KNOW FOR SURE the throttle body is clean. Once set, it shouldnt *ever* need to be touched. If it ever goes out of whack, you need to clean the throttle body or find the REASON its out of whack.

In other words, start with a clean throttle body, set it all up, IAC at 10 to low teens in P and high teens to low 20's in D, TPS .42-.44. If it ever goes out of whack from there, the throttle body is dirty or theres a vacuum leak etc. There is a REASON it goes out of adjustment. Dont use this "adjustment" as a fix as its not there for that, its to set the MINIMUM AIR the engine will flow BEFORE the ECM makes its adjustment. Thats IT!

After awhile of watching HOW the ECM adjusts/corrects, you will know if and HOW dirty your throttle body is, OR is IAC is LOWER than normal, that there is a vacuum leak or other air entering the engine

 

[timothydog]

Good point Jim..
I get oil in my throttle body every once in a while from the PVC and it gunks up my idle air channel.

 

[wiked87gn]

what about setting your TPS>

what if ur TPS is set to .46, is that still OK?

 

[Rick]

DONE!!!!!!!!!! One thing though. I was keeping it running while doing all the adjustments. It went from 100 down to 48 when I decided to turn it off and restart it. When I restarted it the IAC was then down to around 16!!!!!!!!! Can't complain but I was wondering what would have happened if I wouldn't have turned it off and restarted. I checked it 3 times later and it is hanging in there. No more dying when he lets off the gas. Also I took the previous advise and pulled the TB off and cleaned it.

Thanks as always guys, you got me through another one

 

[Bens87tr]

When I was doing my IAC adjusments today, whenever I tried to lower them the rpm's would go up. I can't get the idle down to the 750 rpm like the extender chip is programmed at. What gives?