Idle adjustment help

sssammm

Enthusiast
Joined
Dec 9, 2010
Posts
421
Reaction score
0
Location
United Kingdom
My SRT-10 is idling at 1060 rpm, I have tried the idle screw in the
throttle body, waited for the PCM to adjust down the revs, but nothing happened.

my car has had the battery disconnected a couple of times and wondering
if this bit of info below would apply to me, if not, any ideas?





This procedure must be followed if the battery is ever disconnected or drained to the point of the car not starting.



"1. Disconnect all three PCM connectors for about 10 minutes. By doing this, you are erasing the PCM adaptive memory.

2. Disconnect the TPS (throttle position sensor) on the driver’s side of the throttle body. Ensure all wire connections are correct.

3. Disconnect the IAC (idle air control motor) on the air plenum located on the passenger side directly behind the air filter. Ensure all wire connections are correct.

4. With the PCM disconnected, make sure the throttle cable and throttle linkage is adjusted properly for wide-open throttle. The driver’s floor mat should be removed as it can inhibit accelerator pedal travel.

5. After wide-open throttle is verified or adjusted, reconnect the PCM, TPS and IAC connectors after 10 minutes has elapsed from the start of this procedure.

6. Turn the key to the "on" position, but DO NOT start the engine.

7. With the drivers floor mat out of the car, slowly press the accelerator to full throttle, then repeat. By doing this, you are showing the TPS (throttle position sensor) full throttle. Without this information in the PCM, it will not correctly calculate how to make the engine run properly.

8. Turn the key off then start the car without touching the accelerator.

9. Let the engine idle for approximately 2-3 minutes.

10. After idling, drive easy, then progressively harder over the course of about 10-20 minutes.

11. The car will drive differently during the first 20-40 miles because the PCM is learning the new adaptives



To get the signal for the A/F gauge, tap into one of the wires coming from the O2 sensor going to the VEC3."
 
Last edited:

bluesrt

Enthusiast
Joined
Nov 17, 2008
Posts
5,011
Reaction score
3
messing with the idle screw will not fix it, may be air leak, tps gone wrong,ect
 

Allan

Enthusiast
Joined
Mar 7, 2009
Posts
2,546
Reaction score
0
Location
La Junta Colorado 81050
Easiest way to diagnose any idle speed concern is with a scan tool that will display a live data stream. (not just a code puller) Need a DRB-III or equivalent. I use a Snap-on Verus. -Look at the IAC PID, should be appx.15-25 counts at hot idle/no load (all electrical and A/C off) If counts are too low or zero with idle above the "desired idle speed"-(another PID in the stream), then the engine is getting un-meterd air from somewhere (vacuum leak). {pcm can't control or meter a vacuum leak and is trying to slow the motor down by closing the IAC valve, hence the low or no counts.} If the IAC counts are up, or higher than 25/35ish, than the high idle is being commanded by the PCM for some reason. Some other input is jacked-up! (TPS high is most common, RE-CAL may fix / or the TPS is defective (again, you can see this in the data stream.)------I know what.....let's ask that EARTH WIRE DUDE......nevermind all that jiberish that I'm trying to help you with..................
 
OP
OP
S

sssammm

Enthusiast
Joined
Dec 9, 2010
Posts
421
Reaction score
0
Location
United Kingdom
Just found a sticky butterfly, didnt close properly, cleaning it up now and will polish the seats

could this be my problem?
 

Allan

Enthusiast
Joined
Mar 7, 2009
Posts
2,546
Reaction score
0
Location
La Junta Colorado 81050
Well, if the throttle blade sticks open just a bit at what is supposed to be closed throttle, there is your TPS high and un-metered air. Actually the PCM thinks your foot is on the pedal. If your data stream shows TPS value in % as well as volts, you will probably see a 2-3% TPS value on that PID. IAC counts will be appx. 60-95ish or higher. If these are your readings, then that is definately the problem! That will make it a "no parts fix". I love it when that happens. :2tu:
 

Allan

Enthusiast
Joined
Mar 7, 2009
Posts
2,546
Reaction score
0
Location
La Junta Colorado 81050
There are some "OBD II readers" out there that have some 'limited' datastream capability. Most are code pullers only. If you don't get a menu screen or option to view live data, then your tool is a code puller only. Won't help with specific pinpoint diagnostics like I'm trying to help you with. (your probably right on the money with the throttle plate sticking though) Need a DRB III, or a scan tool that simulates it to view the data stream.
 
OP
OP
S

sssammm

Enthusiast
Joined
Dec 9, 2010
Posts
421
Reaction score
0
Location
United Kingdom
My ODB2 scanner does live streaming with figures and graph, I suppose i have to go through each PID till i find the right one,

anyway, tried cleaning, polishing, light sanding, but my TB is still sticking, think ill buy a new one with a new TPS
 
Top