If i dont have it set correctly, what does it actually cause to happen? Engine run lean or too rich? what exactly
Ninja Edit: Please help
and Thank you
Ninja Edit: Please help
and Thank you
Question about my TPS
- Thread starter bobiseverywhere
- Start date
It is part of the engine load calculation it uses TPS position & MAP pressure & Air temp to figure out the fuel amount to send to the injectors.
Bad TPS positioning could cause horrible idle check engine light to come on and limp mode engine run.
Also verry little of the load is calculated through the air temp sensor it makes verry little or slight adjustments to fuel based on air temp sensor.
Bad TPS positioning could cause horrible idle check engine light to come on and limp mode engine run.
Also verry little of the load is calculated through the air temp sensor it makes verry little or slight adjustments to fuel based on air temp sensor.
oh i see, Well then i definitely need to set it correctly then, Is it posible to make the engine run to lean with the TPS set incorrectly?
In detail here is what happins you smash the foot pedal because you have a lead foot and the viper next to you is giving you crap.
You open your butterfly up to max sending the max voltage just below 5VDC to your ecu but this could be any from almost 0VDC - 5VDC 0vdc no throttle.
you ecu see's 5VDC meaning there is more air coming into the engine and tells the ecu to set timming and enough fuel for the load your butterfly is requesting.
The your map sensor says yep there is more air in here and this is exactly how much of it and your A/F ratio is directly controled by your MAP thats how SAFC correct this by intercepting map signals and tricking your A/F ratio.
so your MAP is the main A/F ratio tool.
your TPS tells your car when to go into idle mode and what RPM engine speed you are requesting and bases this on the amount of air aprox should be going into your engine.
if this were a 7M it instead of soley map it uses a AFM the AFM haves a map and air velocity meter built into it.
AFM sucks just as obd2 because it is harder to tune & when you have things like BOV vent to atmospere it throws the whole ratio off.
IF your A/F ratio is way off things to check is more likely to be your MAP sensor and you fuel injectors fuel pump fuel pressure do you have your fc/fp wires bacwards running your fuel pump at half voltage all the time??? Vacume leaks also but not as much on a maps system that reads from the plenum.
worse comes to worse get a AFC2 and see if you could tune your ratio back in then start checking injector driver caps ecu fuel injectors map sensor etc..
Did you installe a walbro or the jza-70 fuel pump? jza-70 use a better one:naughty:
You open your butterfly up to max sending the max voltage just below 5VDC to your ecu but this could be any from almost 0VDC - 5VDC 0vdc no throttle.
you ecu see's 5VDC meaning there is more air coming into the engine and tells the ecu to set timming and enough fuel for the load your butterfly is requesting.
The your map sensor says yep there is more air in here and this is exactly how much of it and your A/F ratio is directly controled by your MAP thats how SAFC correct this by intercepting map signals and tricking your A/F ratio.
so your MAP is the main A/F ratio tool.
your TPS tells your car when to go into idle mode and what RPM engine speed you are requesting and bases this on the amount of air aprox should be going into your engine.
if this were a 7M it instead of soley map it uses a AFM the AFM haves a map and air velocity meter built into it.
AFM sucks just as obd2 because it is harder to tune & when you have things like BOV vent to atmospere it throws the whole ratio off.
IF your A/F ratio is way off things to check is more likely to be your MAP sensor and you fuel injectors fuel pump fuel pressure do you have your fc/fp wires bacwards running your fuel pump at half voltage all the time??? Vacume leaks also but not as much on a maps system that reads from the plenum.
worse comes to worse get a AFC2 and see if you could tune your ratio back in then start checking injector driver caps ecu fuel injectors map sensor etc..
Did you installe a walbro or the jza-70 fuel pump? jza-70 use a better one:naughty:
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cool stuff thanks for the complete answer on this. 
I know it's not perfect but i do have a Apexi TT ATM and it is supposed to have a A/F function. Just need to hook it up. I know it is not the best and just gives a somewhat close idea but for the moment it might help, no?
What you explained makes sense the only thing that gets me is if i move the TPS around the Ilde speed of the car changes? if the ECU is checking the map as well wouldn't the map be saying not no go and the idle should stay the same?
Well an AFC2 or AFC NEO is on my list of stuff to get. Provided i keep the car
I know it's not perfect but i do have a Apexi TT ATM and it is supposed to have a A/F function. Just need to hook it up. I know it is not the best and just gives a somewhat close idea but for the moment it might help, no?
What you explained makes sense the only thing that gets me is if i move the TPS around the Ilde speed of the car changes? if the ECU is checking the map as well wouldn't the map be saying not no go and the idle should stay the same?
Well an AFC2 or AFC NEO is on my list of stuff to get. Provided i keep the car
TPS also tells the ECU to cut injector off when the throttle is closed. Then the ECU monitors rpms and appx. 200 rpms above idle, cuts the injectors back on so you don't stall.
I need to know the exact symptoms of your car to say exactly what it is.
Your A/F could be way off and dont mater how much you try to adjust the tps or map it wont affect it.
Lets say your were not paying attention to our advice on other threads and you put those TLF or VENOM injectors in your car and it runs like crap you cant really blame the TPS for this.
The TPS is a major PITA to adjust! it is best to leave it factory and not mess with it. or mark the set screw placement if you must remove it for any reason.
You basicaly have to adjust it using a meter connect it to the earth pin i believe & the idle and gently remove pressure or any force at all from the throttle so when it is resting in idle it will always be around this positon.
now rock your TPS back and forth in the set screws just when the cam kicks in the idle and you get continuity SET it there with the set screws then tap the throttle a couple times and verify that in idle or rest position only that you get continuity to the idle pin then it is adjusted to where it should be!!!
once you have it adjusted check the resistive material by going from VCC to earth this should be a fixed value dont mater where the tps position is!!
next check the wipper by going from VTA to VCC and moving the throttle this should be leanier and have no missing values and you should get the same effect going from VTA to earth but it will be inverted once you know for sure your TPS is positioned right and it works well set it there and never touch or move this thing again!
Your A/F could be way off and dont mater how much you try to adjust the tps or map it wont affect it.
Lets say your were not paying attention to our advice on other threads and you put those TLF or VENOM injectors in your car and it runs like crap you cant really blame the TPS for this.
The TPS is a major PITA to adjust! it is best to leave it factory and not mess with it. or mark the set screw placement if you must remove it for any reason.
You basicaly have to adjust it using a meter connect it to the earth pin i believe & the idle and gently remove pressure or any force at all from the throttle so when it is resting in idle it will always be around this positon.
now rock your TPS back and forth in the set screws just when the cam kicks in the idle and you get continuity SET it there with the set screws then tap the throttle a couple times and verify that in idle or rest position only that you get continuity to the idle pin then it is adjusted to where it should be!!!
once you have it adjusted check the resistive material by going from VCC to earth this should be a fixed value dont mater where the tps position is!!
next check the wipper by going from VTA to VCC and moving the throttle this should be leanier and have no missing values and you should get the same effect going from VTA to earth but it will be inverted once you know for sure your TPS is positioned right and it works well set it there and never touch or move this thing again!
haha. Yes. Setting TPS voltage is a major PITA. If you have a Power FC + Commander, it is a little easier though.
I don't have any major symptoms. The problems is that i had moved it before and now need to set it back properly. I am probably going to get a multi meter today so i can work on this,
I pulled the plugs yesterday and checked the compression. almost all perfect 160psi and all the plugs were nice and clean as a whistle. I have never seen plugs so nice and clean.
ninja edit, Also all my coil packs had cracks in them which i did not notice before. I put a temp seal on the cracks for the moment
I pulled the plugs yesterday and checked the compression. almost all perfect 160psi and all the plugs were nice and clean as a whistle. I have never seen plugs so nice and clean.
ninja edit, Also all my coil packs had cracks in them which i did not notice before. I put a temp seal on the cracks for the moment
To adjust the TPS, conenct a multimeter between the IDL line, and I think it's the VE line. place a 0.4mm spacer in front of the throttle adjustment screw, and adjust the TPS so that you just see continuity. Then, take the spacer out, and make sure there's still continuity, move the throttle a little bit, and make sure that the continuity dissappears just over 0.4mm. It's a little bit of a bitch to get right, but it really helps.
Heh, I think most people mess with it, then go "ah shit, I shouldn't have touched that"Evilempire1.3JZ-GTE said:
I messed with mine, then had my V-pro installed. The V-pro was calculated to the incorrect TPS settings, so I had to adjust it, then get the v-pro re-calibrated. That was a PITA.
annoyingrob said:Heh, I think most people mess with it, then go "ah shit, I shouldn't have touched that"
I messed with mine, then had my V-pro installed. The V-pro was calculated to the incorrect TPS settings, so I had to adjust it, then get the v-pro re-calibrated. That was a PITA.
ya i bet it was a PITA