1987 Ford Mustang throttle position sensor

FOXMUSTANG2

MEMBER
1987 FORD MUSTANG

Engine Performance problem
1987 Ford Mustang V8 Two Wheel Drive Manual

hey im doing a restoration project on a fox body 87 gt, I have done some modes such as cobra intake upper and lower, bigger throttle body and other bolt ons, I also have done a maf conversion. The car will run but idles up real high sometimes and other times it runs fine. I changed the idle air control and am now looking at the tps but cant tell if this is actaully causing this, when I adjust the tps it gets better but still idles rough and seems like there is a vaccuum leak, I cant find one tho, do u have any suggestions, this is a stock tps but dont wanna replace it until I kno its junk. Alos I have rmoved egr as well, could it be a dirty connection to the map box maybe, any input will help. Thanks

3 Replies

RACEFAN966

MECHANIC
5,029 POSTS

Ok before doing to much here do you have a digital multi meter? What I would like you to do is test the TPS to see if it doing what it should do. What you will need to do this is a multi meter and a paper clip. Let me know if you what is needed and I will walk you through the test and we will see if it adjusted correctly and if it working as it should. Get back to me and we will go from there. The mass air flow kit who's is it Ford Motorsport or?

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Wednesday, April 21st, 2010 AT 10:40 AM

FOXMUSTANG2

MEMBER
6 POSTS

I tested tghe tps today and it is getting power but with a weak light on a 12v test light, I heartd they run around 5v so is this corrects, I also put back on the stock throttle body because the new one is adjustable and I still have the same problem the car will start but will barely idle and when it does it will idle rough, black smoke adn stall, the maf is a ford racing one out of an 89 with the computer. I called a mustabng place they said it just might need to be tuned, anymore suggestions? Also I can get a multi meter and ill do the test ur way. Thanks for the help a

Was this

answer

helpful?

Yes

No

Wednesday, April 21st, 2010 AT 3:35 PM

RACEFAN966

MECHANIC
5,029 POSTS

Ok that is not how you test the TPS you need a digital multi meter. I will walk you through the test when you have one. You need 5 volts to the sensor but the important part from there is what signal is it sending back to the computer and without a digital multi meter we can't check. Also don't use a test light to test computer sensors this can cause problems or take out the computer as it demands power to operate where a meter uses it's own battery for power. Get back to me when you have a meter and we will go through the test from there. I will get the wire colors and such and if you like put the performance throttle body back on and we will go from there with what you will be running. I have many mods on my 98 and have no running problems.

Was this

answer

helpful?

Yes

No

Thursday, April 22nd, 2010 AT 9:37 AM