Throttle Position Sensor

[bucketmouth]

I have a 93 Mustang GT 5.0 L H.O. Motor in my coupe. The TPS is playing up, can some one tell me are these just a remove and replace sensor or is it adjustable and has to be set after fitting it. I read somewhere that it can be adjusted but I can't see how as the two hold down screw holes are round not slotted so it is fixed when screwed down.
Any one?

[enjenjo]

They are adjustable to a degree. You have to set the resistance to a certain range with the throttle closed I believe.

[rooster]

Maybe something to grow on!

Let us know what happens.

[kb426]

There is an exact setting procedure available from Ford racing's website. If you can't find it, I'll see if I can find my copy. If your's in eecv it may need slots to be enlarger if it isn't the correct volt reading.

[jaybee]

On a lot of cars the TPS will tend to develop a "dead spot" where the throttle is held for extended periods of time. Not a lot to do in that case but replace it.

[kb426]

1.) Clean TB with carb cleaner and nylon brush (a toothbrush works great). Engine off, fully open TB blade and spray/brush TB until all gunk and oil residue is cleaned.

2.) Allow to dry, or close TB blade and start engine until it clears all carb cleaner fumes/liquid.

3.) Let engine idle, if it doesn't, increase idle speed via TB stop screw until engine stays idling on its own. Continue to let idle until it engine is warm(or until computer switches to Closed loop mode at around 140-150 Deg. on the ECT(Engine Coolant Temp.)).

4.) Disconnect IAC valve, if engine dies repeat step 3 with IAC disconnected.

5.) Set idle speed to the lowest setting possible between 650-850 rpms with IAC disconnected. It is key to use the lowest possible to prevent idle surge, rolling, etc once the IAC is reconnected.

6.) Turn engine off, and reconnect IAC

7.) With Key On Eng Off(KOEO), check TPS voltage output. If it's between .7vdc - 1.0vdc(the middle ground as will be discussed below), it's OK. This voltage check should be done between the Green and Black wires at the TPS side of the connector, do not disconnect the TPS connector for this test... Use (-) terminal of the DMM(digital multi-meter) on the Black wire and (+) terminal on the Green wire.

8.) Disconnect battery (-) for 3-4 minutes. Reconnect battery, start engine, allow it to idle for 2-4 minutes to confirm setup,

9.) If idle speed falls too low or stalls, increase idle speed via the TB set screw a little at a time.

10.) Turn engine off for 20 seconds, re-start engine and repeat step 8-9 if stalling occurs.

11.) Reconfirm TPS output is within the .7vdc - 1.0vdc range... you are done!

[bucketmouth]

Thanks guys for the info,im away at work at the moment but when I get back home I'll have a look at it.
I did clean the sensor and had some success when I first started  the car,it drove ok but the next day it would revert back to the fault.
Meanwhile I'll order a new sensor from the states as we dont have them down here and I'll take it from there.

cheers

[bucketmouth]

I'm going to buy a new ECU for my coupe. The old one has this code written on it.Anyone know how to decipher it?
Does the code refer to the chip or is it written into the ECU unit itself so if I change out the ECU will that code be gone?
So what I'm asking is will I be able to replace the ECU and fit the Super Chip to it and it will function the same, that's what I really want to know?

[kb426]

There are many codes on the ecu but as I remember what was important  was whether it was for an auto or manual trans. There was a speed density version and mass air versions. The cobra version is calibrated to use 24 lb injectors with 19 lb programming. I've seen pics of cases cut open to install a chip but I know nothing about that. I saw guys using a Tweecer to reprogram most of them. I think if you google the number on the ecu, you will find a listing of whether it's v8 or 4 cyl and trans, etc.

[rooster]

You might try these if you havent yet.

http://easyautodiagnostics.com/ford_tps_4.9L_5.0L_5.8L/bad_tps_test_1.php

[kb426]

Might look at this.
http://books.google.com/books?id=dc7z5W6e-EsC&pg=PA103&lpg=PA103&dq=eec+iv+ecu+listing&source=bl&ots=Ri78WF5kBf&sig=NSEb8pt0qJr1DSkSa7iBme1OP4Q&hl=en&sa=X&ei=eEVoU47QGcidyASJ54KoAg&ved=0CEIQ6AEwAzgK#v=onepage&q=eec%20iv%20ecu%20listing&f=false

[wayne petty]

what exactly is the issue??? random stalling...

can you run a few tests for me...
start with this one.. its really simple and quick and has solved many many issues for me..

you will want to print the image of and paste it to the side of your tool box or shop wall.. the 4 part section is really important..




then


if you have the conventional TFI ignition and not an MSD ignition..

stick the probe of a test light into the coil positive connector cavity.. ground the clip end.   i usually disconnect the starter solenoid push on connector..  i then rotate the key from off thru ON, Crank, back to ON, then OFF..  you should not have any drop out in power..

do a similar test on the probably RED wire on the idle air control valve..  that is controlled by the EFI main relay.. the coil is directly switched by the ignition switch..  

the EFI main relay is also controlled by the ignition switch..

since you have access to the ECM.. after you have checked KOEO and KOER self tests...   disconnect the ECM and keeping ONE hand always on the computer.. remove the cover screws and examine the circuit board.. please don't hand it from person to person without shaking hands before handing the computer to the next person.. you don't want static..

examine the circuit board for cracked solder joints..


see the red B in this image..  that is a suspect solder joint.. i resoldered all the ones below it. but this is a toyota computer..




here is an 89 /90 ford computer i did some solder repairs on..  the coating is so thick that it makes it really hard to solder it without wire brushing the coating off.. and then there is all the surface mount stuff.. i ended up using a small screw driver and mashing the solder joints to reestablish the contact.  instead of fighting it..  and it did restore normal operation .. the owner still has not replaced it..  but will soon..




grounds grounds grounds...



please disconnect #20 and #21 in this image. its the round 10 pin connectors  you may want to go in with a very sharp carbide scribe and close the gaps in the tubular female pins in that connector take them from a C to a O  without making them into a D or a G shape.. this is a hidden fault that stumps a lot of techs..





here is the engine side of the harness..  note the ground connections i pointed out..  each one grounds a different circuit.

#14 and #15 are the other side of the 10 pin connectors to look at..



this is what a lot of people are using to gather KOEO and KOER codes if you don't have a scan tool to assist you...



close to the end of the KOER self test.. you are instructed to GOOSE the throttle.. this is a REALLY FAST opening then slamming shut of the throttle.. you don't want to  have the throttle open long enough for the engine to accelerate more than 3000 RPMs..  just a really quick open close..  what this tests is the detonation sensors.. lets the computer know that they are working .. you may hear it Ping once or twice..

the engine to firewall braided ground strap is really important that it is properly attached ..


Engine Control Computer - A1 CARDONE [Reman.]
Part Number: 78-4352
5.0 Liters and 5 Speed and Exc. Convertible; w/I.D. #F3ZF-DA,DB, E9ZF-AA

[bucketmouth]

Thanks for all the info guys that is excellent. I'm still away from home but I have ordered a new TPS from the states and hopefully that will be delivered by the time I get home.
My computer is a manual but the car is an auto. I know this is can be done but what the modification has been carried out to allow this I don't know. It's something else for me to find out about the car.
I wish I knew who the original builder was.
Thanks again for the advice.

[wayne petty]

there are several books on the EEC4 system...

there are even so TRULY neat tools that can connect


start with reading almost every page on this site..

http://oldfuelinjection.packrad.net/page1.html

and guess what.. if you learn EECIV.. you can transfer that knowledge to most oem fuel injection systems..   amazingly they all work almost the same.. there are some variations..  i started with feed back carbs.. and then moved backwards into mid 70s cadillac EFI.. where you had to measure each item.. then moved forward where i am fairly skilled at OBD2 stuff now..

you will want to drool over this site..

http://www.racesystems.com/sneeciv/sneec.htm

here is a FAQ that might help also..


http://www.allfordmustangs.com/techarticles/EECTuner_FAQ.pdf

oh... i have the eeciv probst book.. the old fuel injection has more info.

[bucketmouth]

Thanks Wayne for all the info it's nearly intimidating just looking at it all. My new TPS arrived to day for the coupe,I'll get onto after I sort out my problem with the roadster over the next day or two.