Clacor

iTrader: (3)

Hi,

After installing my new PFC I reseted and started to lear the Idle process...

After 10 minutes the idle was over 2000RPM




Trying to find an answer by myself I noticed thei weird value on the VTA2 TPS



Too high for a closed throttle on idle.

So I went ahead rotated the TPS as described on many post.

Weid thing is if I rotate it ANY Voltage value changes on the Power FC, and even if I unplug the TPS voltage value does not change at all in the Power FC.

What am I doing wrong ?? My understading is voltage reading on PFC should change as I rotate the tps ??

Please help..!!!!!!!!!!!

Thanks...

DaleClark

iTrader: (55)

It's either the TPS or the wiring to the TPS. Test it per the shop manual and find out.

Dale

Clacor

iTrader: (3)

Dale, am doing all this testing with a cold engine.

I ended up removing the TB to test.

So if I rotate the TPS, and if it is still connected to harness voltage should change on the PFC sensor reading ??

Thanks..!!!

Clacor

iTrader: (3)

Ok, just an update.

I found a disconnected ground on same wiring coming from TPS, I grounded but still no Voltage variation when I move throttle.

I don´t think is wiring as the harness looks pretty much new.

Am in the process of getting a new TPS. Sounds good to you ??

Or something else to check ??

What looks weird is that is unplug the TPS connector the PFC still holed the same voltage reading. is it Ok ??

Thanks..!!

DaleClark

iTrader: (55)

Yep, that's normal. The PFC will just show full open if it's not getting a signal.

Might also be worth testing continuity on the wire from the TPS to the ECU. TPS's don't fail that often, and a break in the wire would do the same thing.

But, you can get a good used TPS for pretty cheap.

Dale

95WhitePEP

Funny TPS story on another vehicle....

I had my TPS fail on my Jeep and when I would stop, the engine would rev up . I got into the habit of staying on the brake....that or I would lurch forward....came close to back ending a few cars.

WTF I thought my Jeep was possessed....

MazdaSpeedDan

iTrader: (4)

If you tested it and its still acting up I would suggest you have a bad TPS. Idling at 2k could be caused by a bad TPS. If you followed the FSM what readings are you getting from the Multimeter when you are checking it? If the readings are way off when you are at WOT and CT then you can 100% know if your TPS is bad.

Clacor

iTrader: (3)

Thank you guys, it´s unbelievable how helpful is this forum....

I got the TPS out of my car, I will test it tomorrow.

I did the Carb Cleaner test and no obvious vacuum leak, I checked grounding do I isolated the issue to the TPS or wiring.

More news tomorrow...

Gracias nuevamente a todos...

zammm

iTrader: (6)

I had problems with my TPS sensor voltage...the car would buck REAL BAD...all it was, was that the connector was dirty..i cleaned it...put some conductive electrical grease and the problem went away.

Clacor

iTrader: (3)

Ok, so here is the update...

I got a WORKING TPS from a WORKING CAR.

Once I plug to the harness, but not in location yet this is the reading I get at the PFC...







And once I install it in place, the reading does not change... It is still remarked in BLACK...

WTF ?? I don¨t know what to do now... Is a working TPS and the PFC reads like malfunctioning sensor ??

Ayuda...!!!!

MazdaSpeedDan

iTrader: (4)

You adjust the TPS by rotating it on its screws, you need to test it at WIDE OPEN THROTTLE and closed throttle, you need to attach your TPS to your throttle body and manually test it. If you notice when you pull the throttle cable it moves the **** where the TPS goes, that then moves the bracket in the TPS which sends the voltage to the computer.

Clacor

iTrader: (3)

I see, and why does the PFC reads a sensor failure when I plug the new TPS to harness ??

DaleClark

iTrader: (55)

Because the TPS is at absolute zero, which is an out-of-range reading for the ECU, so you get all black. Install it in the throttle body and adjust it and you'll be good.

Dale

Clacor

iTrader: (3)

Guys, first of all I can´t tell how much I appreciate your help on this matter.

Finally adjusted a few things and now TPS voltage is fine.

So I resetted the PFC, started the car, and Idle is at 2000 RPM again ..!!!!!!!!!!

Am pretty sure there is no such a huge vacuum leak that can make it happen.

I don´t know what to look up now... This is so frustrating...

milano maroon

iTrader: (1)

don't know what all you have checked so far, but here are a few things to double check -

make sure you don't have a vacuum leak

no vacuum hoses disconnected

too tight a throttle cable - need about 2mm slack

check the voltages on both ranges of the TPS - make sure that the engine is warmed up and the fast idle plunger is not opening the throttle when you set the voltages

make sure the idle adjustment screw is set correctly - may have to search for this procedure or try backing it out when running to see if speed lowers

maybe take the elbow off and see how the throttle plates are positioned at idle

are the PFC idle settings correct?

good luck

Meiogirl

iTrader: (2)

I wanted to reply to this thread because this was my same issue and the thread seemed to die with no answer to the situation listed above.

If you are getting the image above when installing a working, or new TPS you have installed it in-correctly. You are also getting no sort of reading when you turn and try to 'callibrate' it.

How to fix? You need to make sure the U footings of the TPS are in the correct place on the mounts throttle side and turn the TPS down towards the Oil filter. Do not force anything, you should feel little to no resistance from the spring as you turn. Less resistance than from turning it the wrong way. You will instantly see changes in the commander.

RotaryEvolution

iTrader: (30)

yeah well, since no one else mentioned it yet....

did you guys remove the 4 pins from the engine harness at the ECU as noted in Dale's PFC FAQ writeup stickied in the PFC forum?

the idle will not set correctly unless you do. don't bother trying to learn the idle until you do either.

Meiogirl

iTrader: (2)

hey man!

don't know about the other guy. my fd as of now seems to be 100%. of course this car came to me as it is, what your are suggesting might have already been done. the idle cam on mine is deleted/bypassed so it seems as if this car has seem some issues before. i will check it for sure. thanks.

RotaryEvolution

iTrader: (30)

if the rest of the idle control solenoids are blocked off then it wouldn't be related but don't know if that's the case with your car or not. there would be block off plates on the backside and underneath the UIM after the throttle body.

to see if the wires are disconnected, just pop off the passenger side door sill plate and kick panel to access the ECU and see if there is 4 wires either cut, taped up or disconnected and shrink wrapped. in some more extreme cases the installers removed the pins from the ECU itself which is a little trickier to tell.

if there are block off plates for the idle solenoids then your idle set screw(front of the throttle body facing upwards) and air bleed screw (under the throttle body elbow)are the only things that can raise the idle and set it with. the TPS would only affect ignition timing at that point and affect idle marginally.