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Engine IDLE / TPS

  • Thread starter Thread starter LATT5133
  • Start date Start date Jan 4, 2021
L

LATT5133

Member
May 8, 2020
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Tampa, Florida
Jan 4, 2021
#1
  • Jan 4, 2021
  • #1
Gents, I have scoured the site looking to see if there are similar issues, I replaced the factory EGR spacer and TB with a BBK unit. I followed the BBK instructions on idle and TPS setting. After driving I came back and checked my code scanner KOEO and pulled 23. TPS out of range. The car did idle, a little off, but ran great otherwise (maybe a bit rich?). When I got home I warmed her up and unplugged the IAC reset the idle, lower 600'ish, then checked TPS .80.

*NOTE* .80 is all I can get, the part of the TPS block where the wiring pigtail comes out is flush against the TB flange. This is as far as it goes since I shaved as much as I believed possible without eating into the wiring? This may be where my issues lie?

After checking TPS I shut her down and removed the negative cable for 10-15 min. After 10-15 min I plugged in the IAC and re connected the negative battery cable. Cranked her up and let it run with no accessories on for 2 minutes, idle may have been 800. Shut it down for 2 minutes then re started with all accessories on (max AC, max blower, and all lights) idle was same 800-ish, let it run 2 minutes. Pulled in the garage and shut down. Pulled codes again (KOEO) pulled code 23 again...

I am sure I am doing something wrong here- Piercing green and black wire on TPS and using DVM. I am pretty sure I have the slot of the TPS in the right side of the TB blade. One thing that I have changed is I removed the 10 pin connector TSB fix as they make it a PITA to simply change a PCV. I did the 10 pin fix by enlarging the male connector ends to make better contact and I have plenty of slack in the wire loom?

Thoughts?
 
D

Deleted member 215073

Jan 4, 2021
#2
  • Jan 4, 2021
  • #2
Aftermarket TPS?
 
L

LATT5133

Member
May 8, 2020
51
20
18
Tampa, Florida
Jan 5, 2021
#3
  • Jan 5, 2021
  • #3
JMGlasgow said:
Aftermarket TPS?
Click to expand...
Yes, came with BBK TB. Still have original and same result on BBK TB?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,167
17,862
224
Massachusetts
Jan 5, 2021
#4
  • Jan 5, 2021
  • #4
.80 is in the proper range. The actual range is 0.5 to 1.25V which is an acceptable setting.

Did you erase the code, and then rerun the codes? It won't disappear on it's own if it's a Continuous Memory code
 
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7991LXnSHO

wanna catch the space herp
10 Year Member
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Jan 5, 2021
#5
  • Jan 5, 2021
  • #5
I found the procedure on this site best for setting the base idle speed when I got a whistling BBK TB and EGR spacer. I hope @jrichker will post it if it’s not in the surging idle checklist that you will want to print out for use anyway. You will also want it to read how to test the TPS.

Help me create the "Surging Idle Checklist"

Updated 26-Oct-2019 to clarify creeping idle RPM increase as the car is being driven. Many of you are familiar with the "Cranks OK, but No Start Checklist for Fuel Injected Mustangs" checklist and the No Crank Checklist. They are very effective in finding and eliminating the problems by use of...
www.stangnet.com

If your tps base voltage was really out of range at idle, the slots can be elongated with a jeweler’s round file, like in a set from HFT.
Edit, micro files might be a better description to find a mouse tail file.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
Jan 5, 2021
#6
  • Jan 5, 2021
  • #6
I've heard them called a 'rat tail file'
Maybe 'mouse tail file' is more politically correct?
Anyway give us a pic of you tps on the tb if you can.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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Jan 5, 2021
#7
  • Jan 5, 2021
  • #7
General karthief said:
I've heard them called a 'rat tail file'
Maybe 'mouse tail file' is more politically correct?
Anyway give us a pic of you tps on the tb if you can.
Click to expand...
You got the pun. A regular rat tail file is too big.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
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203
polk county florida
Jan 5, 2021
#8
  • Jan 5, 2021
  • #8
7991LXnSHO said:
You got the pun. A regular rat tail file is too big.
Click to expand...
As opposed to an irregular 'rat tail file'?
What about a 'red rat tail file'?
Ok, that's enough shenanigans, now back to the regularly scheduled problem.
 
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7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
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Kearney, NE
Jan 5, 2021
#9
  • Jan 5, 2021
  • #9
The BBK TPS usually is a quality part. I’d still check it’s sweep and max voltage.

And a rat bastard file will have big teeth.
 
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L

LATT5133

Member
May 8, 2020
51
20
18
Tampa, Florida
Jan 5, 2021
#10
  • Jan 5, 2021
  • #10
Mustang5L5 said:
.80 is in the proper range. The actual range is 0.5 to 1.25V which is an acceptable setting.

Did you erase the code, and then rerun the codes? It won't disappear on it's own if it's a Continuous Memory code
Click to expand...
will do in a few, I am going to reset the base idle, I think I have it to high in traffic I am idling around 950 ish so that is one issue. I am also going to pull back the TPS to .6 - .7 so it sits a little more square on the mount since that is in range still. I will clear the computer and re check, then go from there.
 
L

LATT5133

Member
May 8, 2020
51
20
18
Tampa, Florida
Jan 5, 2021
#11
  • Jan 5, 2021
  • #11
Ok, I went out and followed jrichker's base idle reset instructions and then "free style" adjusted my TPS, it looked like it was pushed to far one direction, twisted it back about 1/16th in. Cleared my codes and cranked her up. Idled purrrfect! Let it run for a bit and shut her down. Pulled my KOEO codes... 11's for O and C. Cranked back up just to check TPS and she is holding .67 (within spec). We will see how she runs cold in the am! Thanks for the help fellas!!
 
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7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Jan 5, 2021
#12
  • Jan 5, 2021
  • #12
Rat Fink sends his congratulations
and is drooling about how clean it looks under the hood.
 
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L

LATT5133

Member
May 8, 2020
51
20
18
Tampa, Florida
Jan 5, 2021
#13
  • Jan 5, 2021
  • #13
7991LXnSHO said:
Rat Fink sends his congratulations
and is drooling about how clean it looks under the hood.
Click to expand...
Thanks man! Got to have a clean work surface! It was pretty well taken care of through the years!
 
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foxbodybill89

Active Member
Jan 19, 2020
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Sioux Falls, SD
Jan 21, 2021
#14
  • Jan 21, 2021
  • #14
Just a word of caution, I have a BBK TB also and it worked ok for a little while, then I started having hanging idle and weird downshifting behavior. Also couldn't set the base idle for the life of me. I figured out the BBK TPS was crap, put a Motorcraft one on and all the problems went away. Even if you have it fixed now I would put an OEM TPS on.
 
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