• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Need TPS test confirmation

  • Thread starter Thread starter vristang
  • Start date Start date Aug 22, 2005

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Aug 22, 2005
#1
  • Aug 22, 2005
  • #1
I looked in the fuel injection book by Probst, and it says that the tps signal at wot should be 4.5v. I have been getting 4.66v. I am able to get the idle setting to .99v pretty easy.

I am just wondering if anyone else has any other way to determine functionality of the tps.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Aug 23, 2005
#2
  • Aug 23, 2005
  • #2
Other than lookin for a nice clean sweep from your baseline to WOT, with no dips (just linear action) is about it that I know of that is feasible.
The final reading is not normally exactly 4.5 volts. The puter recognizes WOT at 3.7 volts IIRC.
Good luck Jason.
 

cup1981

New Member
Aug 22, 2005
42
0
0
Aug 23, 2005
#3
  • Aug 23, 2005
  • #3
Nope, you can only test the voltage of the TPS, unless you have a Modis Scanner, which goes into more detail. Basically all you can do is drive it and see if you have erratic shift patterns and sitting at idle push the gas slightly to get to about 1500 RPM then floor it, if it sounds like it is hitting a rev limiter than you have a problem. The problem w/ that is that the problem can be in another area if these symptoms should occur.
 

dkins419

New Member
Nov 14, 2004
187
0
0
Michigan
Aug 23, 2005
#4
  • Aug 23, 2005
  • #4
would if make a big difference in anything if you can onlyl adjust your tps to .96v ?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Aug 23, 2005
#5
  • Aug 23, 2005
  • #5
dkins419 said:
would if make a big difference in anything if you can onlyl adjust your tps to .96v ?
Click to expand...
No. The puter should zero it out anyhow. But even for guys who dial it in manually, that is right in the sweet spot.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Aug 23, 2005
#6
  • Aug 23, 2005
  • #6
Thanks for stopping by guys. I appreciate the input.


I did check the linearity of the voltage reading and it seemed ok to me. It never went down and back up.

I guess I need to look elsewhere for the source of my problems.
 

cup1981

New Member
Aug 22, 2005
42
0
0
Aug 23, 2005
#7
  • Aug 23, 2005
  • #7
What kind of problems are you having, Maybe I can help. I have my own shop and my mechanic was wondering what you are trying to do that involves the TPS?

Okay, I see it in your signature, you are having problems w/ a high idle. That can be caused by a vacuum leak, Is your stang Fuel injected, TBI, or carburated. A TPS will not cause a high idle. You are looking electrical, but that problem would be mechanical not electrical unless its idle air control.

One question, have you disconnected the Idle Air control yet to see if it fixes the idle??
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Aug 24, 2005
#8
  • Aug 24, 2005
  • #8
cup1981 said:
What kind of problems are you having, Maybe I can help. I have my own shop and my mechanic was wondering what you are trying to do that involves the TPS?

Okay, I see it in your signature, you are having problems w/ a high idle. That can be caused by a vacuum leak, Is your stang Fuel injected, TBI, or carburated. A TPS will not cause a high idle. You are looking electrical, but that problem would be mechanical not electrical unless its idle air control.

One question, have you disconnected the Idle Air control yet to see if it fixes the idle??
Click to expand...

I ruled out the tps, iac, and other electronic controls a while back, but my mind gets hung up on things and I can't focus on new topics until I feel I have fully explored the old topics. Just had too know what the acceptable range was for wot.

yup, but I am also having trouble with the engine vac pulling too much air through the crankcase. This is giving me 2 problems.
1) I have a very large amount of oil getting into the intake. I did install an oil seperator tonight, so we'll see if it helps me as much as it helped everyone else.
2) The motor is basically experiencing a vac leak as air travels from the TB through the valve cover and eventually out of the crankcase via the pcv. This is the only cause of high idle that I cannot eliminate.

I don't want to get too far from the original topic on this thread, but if you have any advice I am always open for suggestions.
 
You must log in or register to reply here.

Similar threads

2
Running very very rich
  • 2esoteric
  • Oct 31, 2025
  • Fox 5.0 Mustang Tech
Replies
4
Views
305
Fox 5.0 Mustang Tech Oct 31, 2025
Noobz347
S
Engine Stalls when downshifting/coasting
  • Scott_S
  • Nov 5, 2025
  • Fox 5.0 Mustang Tech
Replies
11
Views
644
Fox 5.0 Mustang Tech Nov 6, 2025
Mustang5L5
1
Electrical 1985 mustang gt Led conversion trouble
  • 1985fox
  • Jan 5, 2026
  • Fox 5.0 Mustang Tech
Replies
10
Views
527
Fox 5.0 Mustang Tech Jan 15, 2026
1985fox
1
Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
R
91 5.0l cranks but no start, fuel pump keeps priming
  • Rhubyn
  • Jun 16, 2024
  • Fox 5.0 Mustang Tech
Replies
7
Views
1K
Fox 5.0 Mustang Tech Jul 29, 2024
4cylredfox89
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?