• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

need voltage values (or more)!! Reward $50


Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
:annoyed:hey, does anyone have or know what the proper voltage paramaters are for a tps sensor? i keep triggering a code 23. but i replaced the tps and it still comes up. looking deeper, i checked connections at ecu and tps, i even opened the loom up to see if i could trace the wire to the ecu to check for shorts.. nothing found!! i'm stumped. i'll pay 50 bucks for the person that figures this shi% out!

some more clues..
runs rough for the first minuite or two (hot or cold)

weird feeling while accelerating (like someone is pulling me back)

sometimes while driving the motor will cut out, then in, then out, then in then its ok. only once did it die and not come back on for a few minutes.(been doing this for years!)

i have replaced the 02 sensor, tps, map, even tried a different ECU.

I know one of you can help!
 


Rock Auto 5% Discount Code: 81874766E40C6A 5th, 2022

Psychopete

Well-Known Member
Joined
Aug 10, 2007
Messages
3,201
Reaction score
29
Points
48
Location
FW, IN
Transmission
Automatic
There is a 5 volt reference, signal to computer and ground.

The TPS is a variable resistor, regulates how much of the 5 volt reference gets sent back to the computer depending on how far open the throttle body is. Should be around .98 volts at idle and around 5 at wide open throttle. With some probing of the connector, it's pretty simplistic to find which is which (don't have an accurate diagram w/ me).

FWIW, TPS sweep test should be done w/ an analog volt meter. Basically, just makes sure that the voltage throughout the range stays consistent (no dead voltage spots).

Pete
 

Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
thanks for the quick response

to clarify, should i check the voltage while the truck is running, or can i do it while in ignition setting? and if voltage is less than .90 should i crank the throttle untill it is?
 

Psychopete

Well-Known Member
Joined
Aug 10, 2007
Messages
3,201
Reaction score
29
Points
48
Location
FW, IN
Transmission
Automatic
to clarify, should i check the voltage while the truck is running, or can i do it while in ignition setting? and if voltage is less than .90 should i crank the throttle untill it is?
You can check it with the ignition only on 'Run'. Although checking it while running might yeild different results than not (loose / bad connection?). The code doesn't directly hint at a problem with the sensor itself..

That screw is solely for setting the base idle voltage, computer controls the idle.

From .90 - .98 should be a small tweak. If it doesn't help or make matters worse, just simply set it back.

I swapped a different throttle body and tore it apart to clean it throughly, didn't mark where that adjustment was, and that's what I set mine to (based on information from this site).

Pete
 

Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
ok i'll set the voltage at idle to .90, i messed with the screw and didnt remember where it was supposed to be, thanks for the info. i'll keep posting to keep updates.
 

Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
nothing so far

now i put my tps to the .90 and now my idle is way too high. pulled codes for koeo and got 11's. then did key on engine running and got codes 12, 13, 77. please help. got $50 on it. i swear a personal check will be sent. please help.
 

Psychopete

Well-Known Member
Joined
Aug 10, 2007
Messages
3,201
Reaction score
29
Points
48
Location
FW, IN
Transmission
Automatic
now i put my tps to the .90 and now my idle is way too high. pulled codes for koeo and got 11's. then did key on engine running and got codes 12, 13, 77. please help. got $50 on it. i swear a personal check will be sent. please help.
How low was it before? :icon_confused:

Codes 12 and 13 are generally related to the IAC valve. Was the idle screw adjusted to try and band-aid a previous high idle problem? Does the idle speed change when the IAC is disconnected?

See here:
http://www.fordfuelinjection.com/?p=39

77 means you didn't hit the throttle when it output the goose pulse.

Pete
 

holyford86

Well-Known Member
RBV's on Boost
Joined
Aug 6, 2007
Messages
1,930
Reaction score
100
Points
63
Age
35
Location
Plattsburgh, NY
Vehicle Year
many
Make / Model
Ford
Engine Size
4.0
Transmission
Manual
2WD / 4WD
4WD
Total Lift
7
Tire Size
33x12.50R15
I just set my idle to the following procedure:

get the truck up to operating temp and shut it down.
Unplug the IAC and start the truck (you may have to give it a little bit of gas to get it to start) run it at 2500 rpm for 30 seconds, let off and see where the idle is. If it's at 700 rpm its good, if its not, adjust until it is at 700 rpm.
Shut the truck off and wait about 30 seconds, restart and run at 2500 rpm for 30 seconds, see what the idle is, if it's at 700 rpm shut the truck off and reconnect the IAC, If not repeat the adjustment procedure.

I found this procedure in Shop Key after .9 volts gave me an idle that was way too high. I did this and it runs right at 850-900 rpm at a warmed idle
 

shadetree

New Member
Joined
Sep 9, 2007
Messages
1,794
Reaction score
9
Points
0
Age
82
Location
East Texas
Vehicle Year
1994
Make / Model
Explorer Sport
Engine Size
4.0
Transmission
Automatic
A vacuum leak will give the same symptoms. Make sure all connections, hoses are solid. Don't forget the PCV valve. If it is not working correctly, it will cause idle, stumbling problems. Shaking to see if it rattles is not a valid test. Replacement is.:)shady
 

almostclueless

New Member
Joined
Aug 6, 2007
Messages
1,403
Reaction score
3
Points
0
Vehicle Year
98
Make / Model
ford
Transmission
Manual
Check the wiring to the TFI module. This can be problematic to check, as I've read the wires run sometimes run inside a braided shield....one option is to connect one test lead to the shield, the other to each wire to be checked and flex the TFI harness.
 

Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
thank all of you for the ideas. i'll try em out as soon as possible. shcool and work takes up most of my time. i did move the idle screw to bandaid an earlier problem.
 

Bryan22

New Member
Joined
May 2, 2008
Messages
1,610
Reaction score
3
Points
0
Age
36
Location
So-Cal babay
Vehicle Year
94 extd
Make / Model
Ford
Engine Size
94 2.3
Transmission
Manual
Sounds exactly like the problem i've been having with my ranger... let us know if you figure anything out. So what if the "idle" screw is set out of range? would this mess with the tps and the way the truck runs?
 

Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
aaahh

i have tried everything listed so far and nothing is fixing the problem. now what is happening is i am getting a pip (Profile Ignition pickup) code. and the truck will intermittently shut off while under a load, accelerating. i notice that the rpm gague drops too which leads me to suspect a problem in the wiring or some component that makes the pip loose contact to the eca. any ideas??
 

almostclueless

New Member
Joined
Aug 6, 2007
Messages
1,403
Reaction score
3
Points
0
Vehicle Year
98
Make / Model
ford
Transmission
Manual
The PIP malfunction and the tach dropping when it dies are right in line with tfi related problems (the tfi module, the compuer, and/or the wiring in between).


I'd have a look at the page here about tfi diagnostics
 

Rangermilitia

New Member
Joined
Nov 12, 2008
Messages
60
Reaction score
0
Points
0
Location
San Ramon, Ca
Vehicle Year
1987, for the m
Make / Model
Ford
Engine Size
2.9
Transmission
Manual
its kinda weird...

i have checked all of the wiring.. traced the green/yellow wire from components to eca! all seems fine. i hate intermittent problems.. i replaced my distributor and the tfi module recently. i did however buy a cheap-o kragen distributor.. i'm a little weary about it. but it runs the same as if i had my original one in it. :temper: this is getting very irritating.
 


Top