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PLEASE HELP me with my annoying idle problem!!

  • Thread starter Thread starter Kdubslugga
  • Start date Start date Mar 7, 2004

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Mar 7, 2004
#1
  • Mar 7, 2004
  • #1
Im going to try and explain this as best as i can

At first start up when the engine is cold, it takes about 3 sometimes 4 times for it to run with out stalling out on me. Also when it starts to warm up, when the tranny is in Park or Neutral "AOD" the idle goes up to 2000 rpm, when i shift it into D it drops to about 900 or 1000 rpm. But when i put it back in Park it goes right back up to 2000 rpm. When its at 2000 rpm and i floor it drops back down to 900 rpm and gradually climbs back up to 2000 rpm. This only lasts for 10 - 15 min, but its so friggin annoying. Any ideas of what to check??? Any help will be greatly appreciated.
 

tvmango

New Member
Oct 27, 2003
667
0
0
bradenton florida
Mar 7, 2004
#2
  • Mar 7, 2004
  • #2
I will never understand ricers! All i can say is WHY? (absolutely)

Check for a vac leak, also If you have a way to check the fuel pressure do it.... I bet it's a vac leak, in the intake or a hose....Check to see if your intake bolts are tight...
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Mar 7, 2004
#3
  • Mar 7, 2004
  • #3
Hey thanks for the reply, im gonna do my best to check for a vac leak. Hopefully i find the dumb thing
 
T

thompsonsd

Founding Member
Aug 15, 2002
144
0
0
Southern Maryland
Mar 7, 2004
#4
  • Mar 7, 2004
  • #4
Did you go through and make sure your Base Idle and TPS settings were correct? When was the last time you cleaned your TB?
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Mar 7, 2004
#5
  • Mar 7, 2004
  • #5
Ive never cleaned the TB." I will be doing this tomorrow!!!! How do you check the TPS settings?
 
M

MustangGTee

New Member
Feb 7, 2004
30
0
0
Mar 7, 2004
#6
  • Mar 7, 2004
  • #6
Kdubslugga said:
Im going to try and explain this as best as i can

At first start up when the engine is cold, it takes about 3 sometimes 4 times for it to run with out stalling out on me. Also when it starts to warm up, when the tranny is in Park or Neutral "AOD" the idle goes up to 2000 rpm, when i shift it into D it drops to about 900 or 1000 rpm. But when i put it back in Park it goes right back up to 2000 rpm. When its at 2000 rpm and i floor it drops back down to 900 rpm and gradually climbs back up to 2000 rpm. This only lasts for 10 - 15 min, but its so friggin annoying. Any ideas of what to check??? Any help will be greatly appreciated.
Click to expand...


One of easiest wasy to look for a vacuum leak is using a can of carb cleaner.... spray around the intake, throttle body and vacuum lines. If the rpms climb, you've found a possible culprit.
 
L

Letheo

New Member
Mar 7, 2004
4
0
0
Mar 8, 2004
#7
  • Mar 8, 2004
  • #7
help

Kdubslugga said:
Im going to try and explain this as best as i can

At first start up when the engine is cold, it takes about 3 sometimes 4 times for it to run with out stalling out on me. Also when it starts to warm up, when the tranny is in Park or Neutral "AOD" the idle goes up to 2000 rpm, when i shift it into D it drops to about 900 or 1000 rpm. But when i put it back in Park it goes right back up to 2000 rpm. When its at 2000 rpm and i floor it drops back down to 900 rpm and gradually climbs back up to 2000 rpm. This only lasts for 10 - 15 min, but its so friggin annoying. Any ideas of what to check??? Any help will be greatly appreciated.
Click to expand...
 

jrichker

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Mar 10, 2000
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Dublin GA
Mar 8, 2004
#8
  • Mar 8, 2004
  • #8
Here’s a TPS tip I got from NoGo50…

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .97v-.99v, the closer to .99v the better. Just don’t go over .99, or you’ll upset the fuel calibration and idle quality may suffer, along with some other problems like poor gas mileage.


(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.
 
T

thompsonsd

Founding Member
Aug 15, 2002
144
0
0
Southern Maryland
Mar 8, 2004
#9
  • Mar 8, 2004
  • #9
Kdubslugga said:
Ive never cleaned the TB." I will be doing this tomorrow!!!! How do you check the TPS settings?
Click to expand...

Hi, I can make this pretty easy. See this thread: http://forums.stangnet.com/showthread.php?t=425876 I just went EVERYTHING helping another Stanger out with this.
 
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