Autosport Labs

Hi there,

I have 2 Weber TPS units acquired from 2 separate ford fiestas. 1990.ish, ( number on units are PF07/03. )And, they have 3 wires which return to a 3 pin plug. Which are Red,Green,Yellow.

Is there any way of identifying these wires. For Ground, Signal, Live.

Hope you can help.

Cheers

Ted

Often it's the center plug which is the TPS sense voltage. One end of the plug will be the VRef (+5v) and the other end will be ground.

1. +5v
2. center
3. GND

Using a ohm meter while actuating the sensor shaft should help you confirm the orientation. Measuring between the center and one outer lead should show a high resistance, and the other side low. When the TPS shaft turns to the opposite position, the high resistance should decrease and the low resistance correspondingly increase.

Hope this helps,

Thanks brentb.

Thats sounds like a plan, I thought there would be a better way than just using guesswork.

Once these are connected it's start up time.

Thanks again

Teds

I've just done an installation where the TPS had the 'output' on the left hand pin (ie NOT the centre pin)

You really need a multimeter with a resistance setting to work out how a completely unknown TPS is wired internally...

I've tested the tps as you described and my results are- Red seems to be the centre. Green = high res, Yellow = low res. And green and yellow decrease and increase accordingly when the lever is operated.

So from this can you guys indicted to me what’s what. My guess is.

E.g. Red = signal
Green = +5v
Yellow = GND.

Or have I got it the wrong way round.

I'll try and upload a pic of said TPS. So everyone can see, and if anyone else use's one in their install. For future reference.

Thanks

Teds

If you've got it correct - and it looks like you have - then

green->yellow will be constant resistance (probably around 5k to 20k) whatever the rotation

red->green will be zero at one end of the travel, and close to the constant resistance at the other.

Getting green and yellow the wrong way round won't harm anything - you'll just find that the real time TPS value will be the "wrong way round" in the configurator and you'll have to swap them over.

Here's the TPS sensor in question...





I'll let you how and if it all works out.

Came of a 1990 mk2 fiesta. As did all the rest of my Edis system.

This is its intended new home.



I'll post more pics of my build in the powered by gallery soon.

Cheers

Teds

Teds,

Just one question - where would I find that TPS on a fiesta engine? Is it easy to find?

It looks just right for my current needs...

cheers,
David

david jenkins wrote:where would I find that TPS on a fiesta engine?

On the carburettor!

david jenkins wrote:Is it easy to find?

Yes!

I wasn't sure if it would have a carburettor - that's why I asked

Not that many carb'ed engines had TPS fitted, IIRC.

As MartinM say's bolted onto the carb.

Theres thousands of fiesta's out there for the taking. Also, you can strip the whole EDIS system off in a one'er.

If you do that, re-installing into its new home is much easier.

And make sure you do the same for the TPS including the 3 pin plug.

Teds.

P.S. Sorry about the size of the photo's

Many thanks Teds - I have everything else, and have had it running for quite a while, it's just that I want to fit a different carb on a temporary basis and am looking for a cheap TPS to tide me over until I get the proper bike carb installation finished.

And Martin - my response was tongue in cheek, so don't take it personally!

Got one today!

Came off a Ford Escort circa 1990, and cost me the grand total of £2.35p ($4 approx).

Now to clean it up and devise a way to link it to my Weber carb (see topic elsewhere).

Apologies for hijacking the thread, but it proved very useful for me!

cheers,
David

Oh - while I think of it - the 'carb' was probably a single point fuel injection system.