what will a bad throttle position sensor do on a 1989 351W - 460 Ford Forum
Chilly's Garage A place for non-460 banter.

User Tag List

 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 9 (permalink) Old 11-07-2008, 03:48 PM Thread Starter
Senior Member
 
skosler's Avatar
 
Join Date: Sep 2007
Location: Cistern, Texas (Southeast of Austin)
Posts: 2,021
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
 
what will a bad throttle position sensor do on a 1989 351W

My father in law has a 1989 f150 351w and it does not run very often. He went to crank it up and it sputtered and ran very bad. He thought it was the cap and rotor, so he replaced them. Now it will not fire up or even try to start. New plugs and wires are next, but I don't see how all of them would have gone bad at the same time. I checked all the obvious stuff like firing order and the timing and it looks good. The fuel rail has good pressure and all fuses are good. All connections look good. Spark looks a little weak. This ignition has the module on the dizzy and all the Haynes manual checks come out good. I ran the codes and it shows a #53, TP sensor out of range. If this is bad could it keep the fuel from injecting? I doubt it, but figured it was worth a try.

thanks
stephen [/quote]

Sharpen your pitchforks and light your torches... 'CHANGE' is coming!

We say grace, and we say ma'am, if you ain't into that we don't give a damn... cause a country boy can survive!
skosler is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 11-07-2008, 05:05 PM
Senior Member
 
Join Date: Jan 2006
Location: California
Posts: 525
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
Hello

First you need to find out what the resistance should be set at. Then hook up your multimeter to the pins going to the throttle position sensor and loosen the adjustment screws. Pivot the sensor on its mount until you get the required resistence. Pretty easy.

Hope this helps.

Tom

"The more hair I lose, the more head I get"
747JETMECH is offline  
post #3 of 9 (permalink) Old 11-07-2008, 05:23 PM
Member
 
Join Date: Jul 2007
Location: Las Vegas
Posts: 119
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
Hey dude check out this info on this link its really helpful putting a code scanner is not the same as running a self test BTW I know,

http://sbftech.com/index.php/topic,2471.0.html

This is a page how to read the codes and run engine self tests.

http://sbftech.com/index.php/topic,1031.0.html

That is a page on the base idle reset to hopefully get it back where it should be.


Here is my latest post, read the response should tell you how to read is the TPS is bad, but first try the base idle reset first then go from there.

http://sbftech.com/index.php/topic,17168.0.html


If ya got any more questions ask me I am happy to help


Also TPS being set wrong should not effect spark or injectors, as far as weak spark maybe its a coil, they can be expensive on these cars, I went to a junkyard ford ran the same coil on 3.0 and the 3.8 in the taurus and the 3.0 and 5.0 mustangs and 5.0 5.8 and 460 trucks its all the same some are mounted differently but they all work well with each other if the coil is suspect try using another one.


Good luck
dbu8554 is offline  
 
post #4 of 9 (permalink) Old 11-07-2008, 07:22 PM Thread Starter
Senior Member
 
skosler's Avatar
 
Join Date: Sep 2007
Location: Cistern, Texas (Southeast of Austin)
Posts: 2,021
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
 
Re: Hello

Quote:
Originally Posted by 747JETMECH
First you need to find out what the resistance should be set at. Then hook up your multimeter to the pins going to the throttle position sensor and loosen the adjustment screws. Pivot the sensor on its mount until you get the required resistence. Pretty easy.

Hope this helps.

Tom
I understand that I can adjust it, but I ran out of time today. I was just wondering if it is giving a bad readiung would it keep fuel from being delivered to the cylinder?

Sharpen your pitchforks and light your torches... 'CHANGE' is coming!

We say grace, and we say ma'am, if you ain't into that we don't give a damn... cause a country boy can survive!
skosler is offline  
post #5 of 9 (permalink) Old 11-07-2008, 07:30 PM Thread Starter
Senior Member
 
skosler's Avatar
 
Join Date: Sep 2007
Location: Cistern, Texas (Southeast of Austin)
Posts: 2,021
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
 
Quote:
Originally Posted by dbu8554
Hey dude check out this info on this link its really helpful putting a code scanner is not the same as running a self test BTW I know,

http://sbftech.com/index.php/topic,2471.0.html

This is a page how to read the codes and run engine self tests.

http://sbftech.com/index.php/topic,1031.0.html

That is a page on the base idle reset to hopefully get it back where it should be.


Here is my latest post, read the response should tell you how to read is the TPS is bad, but first try the base idle reset first then go from there.

http://sbftech.com/index.php/topic,17168.0.html


If ya got any more questions ask me I am happy to help


Also TPS being set wrong should not effect spark or injectors, as far as weak spark maybe its a coil, they can be expensive on these cars, I went to a junkyard ford ran the same coil on 3.0 and the 3.8 in the taurus and the 3.0 and 5.0 mustangs and 5.0 5.8 and 460 trucks its all the same some are mounted differently but they all work well with each other if the coil is suspect try using another one.


Good luck
The first sites are a lot better than my Haynes manual, but I got the codes already. I have already replaced the coil, rotor and cap. You say the TPS should not affect the fuel, and thats what I suspected. It must be something else.

thanks for all ya'lls help

stephen

Sharpen your pitchforks and light your torches... 'CHANGE' is coming!

We say grace, and we say ma'am, if you ain't into that we don't give a damn... cause a country boy can survive!
skosler is offline  
post #6 of 9 (permalink) Old 11-07-2008, 07:57 PM
Junior Member
 
PearsonFan's Avatar
 
Join Date: Jan 2006
Location: Tekonsha MI
Posts: 31
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
Quote:
Originally Posted by skosler
You say the TPS should not affect the fuel...

stephen
Unless the TPS were to have failed to a high voltage reading, which is the same as holding the throttle wide open, and is a signal to the computer to go into the "Clear Flood Mode" , which shuts off the injectors. So there is a possablity that the TPS could cause it to not start.

Earl

(Edit) I just checked a buddy's Ford service manual and a code 53 is high TPS voltage ( above 4.84 v) so there is a possability that it could be the cause
PearsonFan is offline  
post #7 of 9 (permalink) Old 11-07-2008, 10:38 PM Thread Starter
Senior Member
 
skosler's Avatar
 
Join Date: Sep 2007
Location: Cistern, Texas (Southeast of Austin)
Posts: 2,021
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
 
Quote:
Originally Posted by PearsonFan
(Edit) I just checked a buddy's Ford service manual and a code 53 is high TPS voltage ( above 4.84 v) so there is a possability that it could be the cause
hmmmmm?

I will check this tomorrow. I guess I could just unplug the sensor and it should fail to a 'safe' position, right?

Sharpen your pitchforks and light your torches... 'CHANGE' is coming!

We say grace, and we say ma'am, if you ain't into that we don't give a damn... cause a country boy can survive!
skosler is offline  
post #8 of 9 (permalink) Old 11-07-2008, 11:17 PM
s_stang
Guest
 
Posts: n/a
Mentioned: Post(s)
Tagged: Thread(s)
Quoted: Post(s)
Edit for good fuel pressure.. Sorry I missed that..

Les
post #9 of 9 (permalink) Old 11-07-2008, 11:43 PM
Senior Member
 
Join Date: Feb 2006
Location: Iowa, near Missery (Missouri)
Posts: 2,286
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
My '94 F250 with 351 did that last winter. Wouldn't start and I dug through the ignition and fuel delivery for an hour before testing the TPS sensor. It was reading like it was at almost full throttle all the time. It was almost impossible to start and when it would start it would rev up and then cut down and then rev up again. The sensor isn't adjustable (clock-able), it just needs the throttle body removed to get to it. It's not a bad job though, takes about a half hour with basic hand tools. I think the wires to test for voltage are the orange and green ones, but I don't remember for certain. Anyway, there's 3 wires and it's pretty easy to figure out which ones to poke with the meter leads.

If they can get you asking the wrong questions, they don't have to worry about answers.
ScottJackson is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the 460 Ford Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome