Ok Mazda you made one funky TPS to put in the FC, and it sucks nuts.

When at idle it reads5-10%
When i press the throttle lightly as possible it reads 50% nowhere near half and its 100
When cruise control is on it reads 83-93%

1. How do I fix this?
2. Should I care? Is it pumping more fuel than it should be because it thinks the throttles engaged more?

thanks fellas

 

Nah, it wasn't that inaccurate from the factory for sure. I bet it is just worn out man. Any adverse effects?

 

Well Im thinking its the reason im getting such shitty mileage. I shouldnt be getting 17.5 mpg highway with new fuel filter, O2 sensor, plugs n wires, and a tune. If when I have the cruise control on and its reading 83-93% It thinks Im flooring it thus giving it the same amount of fuel at that rpm. I dont know though.

 

are you reading it from a safc??? or another instrument tied into the tps sensor?
TPS from mazda are like that, even if you are not stepping on it 50%, it might read 100%.
I know it did on my safc when I wired it in to the tps, which is pretty bad since i dont want what I set at 100% to come out at half pedal, so I did it by wiring the load pressure sensor into the safc.

 

Check the TPS with the Factory Service Manual, it's very simple. I think you are looking at the AFM reading on your SAFC correct, which is not the same thing.

 

no im looking at throttle on safc. which brings up another thing. when i go to 4 channel and the 2nd monitor screen it only displays the highest throttle that ive pressed so far its not a constant changing value. is it supposed to do this. when i go to 2 channel and the 2nd screen it does the same thing on the left and then gives me a real time throttle position right next to it.

 

1. How to fix the problem: buy a Nissan or put an ls1 in your car.
2. Yes you should care because you could hit a speed bump in your car and blow an apex seal

 

Your problem is you have never looked at the TPS when opening the throttle by hand. The TPS is fully extended just about the same time the secondary throttle plates START to open. That's a long way from full throttle.


The TPS at idle, with engine fully HOT, should read one volt dc on pin 2G. That's the pin your SAFC is connected to for the TPS signal.

The TPS tells the ECU when the throttle is in a given ZONE in its travel.

The TPS does mundane things like tell the ECU when to open or shut the Relief and Switching solenoids. Stuff that you'd not be thinking about. That's just an example, not all its functions.

Don't we have a SAFC SUB FORUM?? On this site?

I don't have a SAFC anymore, but from memory it should read zero percent at idle with a HOT engine. Just about the time the secondary plates start to open, it should read real close to 100% and stay that way til the throttle pedal is fully down to the floor.

You can set the TPS using a SAFC display. Just get the engine fully hot and idling well under 1000 rpm. Then adjust the TPS screw til the display reads zero. When it says zero percent, you could take a digital meter and backprobe the wire at the ECU and I guaratee you the meter will read........one volt dc.

When the engine is cold, the TPS, even though you set it right when the engine was hot, will read higher than zero with the cold engine.

Wait til the engine gets fully hot and it should read the ZERO percent once more. This is because the water thermowax moves the throttle linkage open a bit when the engine temp/water temp is cold. Once the water gets hot, the piston on the water thermosensor causes the throttle linkage to go full closed once more causing the TPS to read zero percent again.

 

Thanks ill try adjusting the screw when hot. What does it look like/wheres it at

 

What year car? Turbo or non turob? Matters not. It's shown *how to* in the Fuel and Emissions section of the free FSM's on this site.

Just don't adjust it to the FSM method if you have a SAFC. Just get the engine hot and then adjust it while looking at the SAFC screen for TPS value. That would be a reading of 0 (zero) on the SAFC screen.

There is a SAFC forum on this site for SAFC questions.

If you had a RTEK2.1 you'd set the TPS to 20% since the RTEK is set up a bit different than the SAFC. The 20% being a fifth of the total Voltage put out by the TPS sensor i.e. 1-5vdc. Or one volt equals 20% of 5vdc (higher math, eh?).