1mz-fe old TPS resistance check, what's yours at?

[fenixus]

I suspect a worn out Throttle Position Sensor on my V6 which could be affecting gear shifting timing.
anyways, I did some resistance testing and would like to know what the average correct values are. mine are awkward at fully open throttle (seem low to me, still in specs though).

so, this is what FSM says about testing the TPS on 1mz-fe with A541E transmission:

INSPECT THROTTLE POSITION SENSOR
(a) Apply vacuum to the throttle opener.
(b) Disconnect the sensor connector.
(c) Using an ohmmeter, measure the resistance between each terminal.

Throttle valve
condition.........Between terminals..............Resistance
Fully closed......VTA − E2.............................0.2 − 6.3 kΩ [mine 0.61kΩ]
Fully open........VTA − E2.............................2.0 − 10.2 kΩ [mine 3.03kΩ]
other............... VC − E2..............................2.5 − 5.9 kΩ [mine 3.98kΩ]

here is a screenie from FSM, it shows which terminal is which:


I haven't pulled vacuum on throttle opener, because I didn't have hand vacuum pump with me, but IMHO it affects only the fully closed throttle position and nothing else?

anyways, my question is mostly about resistance of VTA-E2 terminals when throttle is fully open? anybody tested it? what was yours at?

when using OBD2 scanner (engine shut off, ignition ON) I can see my TPS showing values:
a) idling 11.4%
b) floored (at shut engine) 73.7%

thanks.

[fenixus]

another hint that TPS might be getting worn out is that at idle the oBD2 should show TPS value around 7-11% and fully opened throttle should report 65-75% as per FSM Diagnostics normal running engine conditions.

also the fully open % value seems almost at upper edge (73%), but this one actually falls into broad spec range...

here is what ECU uses to calculate the %:

Voltage Output of Throttle Position Sensor Calculated as a percentage:
0 V →0%, 5 V →100%

mine sits at 11.4% at idle (not a real problem I guess) and everything is adjusted OK, no problems with anything I can detect except for delayed upshifting when cold (which is another story I know)... and that could hint that TPS is showing too low values when I operate the throttle perhaps?

[fenixus]

anybody else willing to play with an ohmmeter so we could compare findings?

[Nark]

If you look at the throttle opening chart, there are 8 different % ranges. 7,15,25,35,50,65,85
I pretty sure if TPS stay within that range and in linear forms, it should be ok. The final shift calculation(combination of TPS signal and speed sensors signal) is done within "shift timing control" inside ECT/ECU and we can't really see it unless you put oscilloscope on it.

I think your range is within spec. Can you test it under different angle and see if you can stay within the spec above? I think you can do it without engine runing...just turn ignition on.

Also check to see if IDL-E2 is within range(o-100 for close and infinite for open)...you didn't mention above.

[Nark]

OK I found it. This article said check the Voltages signal at terminal TT on diagnostic plug inside engine compartment. The Voltages will be 1-8V or idle-full throttle in linear format.

I guessed any skip in between Voltage is indicate a faulty TPS...make sure your VMM is true RMS or this Volts will be off. If you take this Voltage and compare it to RPM reading, then compare it to the strip chart in fsm, you might be able to see each gear shift point.

[fenixus]

thanks Nark.

I am aware that TPS is just a part of equation for ECU to determine the shift point.

where in FSM are such detailed tests for the TPS? I only found some simple ohming out in SFI section. seems like there should be more somewhere else?

11.4% at idle seems to be the factory setting on 1mz-fe (gen4) as I have seen the exact same numbers from a different '01 camry v6 which makes me wonder what up.

so, question is why FSM for that camry gen4 (and my model as well) calls for 7-11% on the TPS at idle (Diagnostics section for 1mz-fe - Engine Normal Running Condition sheet) while cars came out of factory with the setting above limit?

I will check voltages between DLC1 (you mean this one by passenger side strut tower?) terminals TT-E2 under hood while operating the throttle. good idea to test it this way.

I have no idea where the IDL terminal would be. my TPS is 3-pin, so it's not there. is it on the ECU end?

Originally Posted by Nark

If you look at the throttle opening chart, there are 8 different % ranges. 7,15,25,35,50,65,85
I pretty sure if TPS stay within that range and in linear forms, it should be ok. The final shift calculation(combination of TPS signal and speed sensors signal) is done within "shift timing control" inside ECT/ECU and we can't really see it unless you put oscilloscope on it.

I think your range is within spec. Can you test it under different angle and see if you can stay within the spec above? I think you can do it without engine runing...just turn ignition on.

Also check to see if IDL-E2 is within range(o-100 for close and infinite for open)...you didn't mention above.

Originally Posted by Nark

OK I found it. This article said check the Voltages signal at terminal TT on diagnostic plug inside engine compartment. The Voltages will be 1-8V or idle-full throttle in linear format.

I guessed any skip in between Voltage is indicate a faulty TPS...make sure your VMM is true RMS or this Volts will be off. If you take this Voltage and compare it to RPM reading, then compare it to the strip chart in fsm, you might be able to see each gear shift point.

[fenixus]

hmmm, I have no terminal in TT slot in DLC1 on neither of cars... I guess it would have be tested in some other way at some other spot (ECU?) ... will leave it for now.

however my TPS is a suspect still until I prove it healthy...

just for the record, here are Throttle % numbers as they come from OBD2 on both Toyotas (v6 & 4cyl):

a) '02 1mz-fe
engine shut & opener pushing the plate 12.5%
engine shut & gas pedal floored 73.7%
engine running at warmed up idle 11.4%

b) '00 5s-fe
engine shut & opener pushing the plate 12.5%
engine shut & gas pedal floored 76.9%
engine running at warmed up idle 11.0%

[Nark]

I don't have camry manual but I was looking at this http://www.autoshop101.com/forms/h16.pdf Scroll down to paragraph right before you get to "direct type. You should've TT(tt) on your DLC1, this is standard pin out. http://www.dtdauto.com/Product/Produ...I%20Scan_E.htm
I saw it on my truck earlier but unfortunately I'm tired to mess around today...
You can do either tt-e1 or e2...or just tt-ground, e is same as computer ground if I'm not mistaken.

[fenixus]

nope, it's not standard on DLC1 for either of my Solaras. I have empty spots where Tt is labeled on both cars.
All I have in that block (around Tt I mean) is Ts and Tc (and AB), no Tt.

will check wiring diagrams to see where this goes, maybe I could measure it at some fuse boxes or junction block or something.

Originally Posted by Nark

I don't have camry manual but I was looking at this http://www.autoshop101.com/forms/h16.pdf Scroll down to paragraph right before you get to "direct type. You should've TT(tt) on your DLC1, this is standard pin out. http://www.dtdauto.com/Product/Produ...I%20Scan_E.htm
I saw it on my truck earlier but unfortunately I'm tired to mess around today...
You can do either tt-e1 or e2...or just tt-ground, e is same as computer ground if I'm not mistaken.

[Nark]

According to this article your A140, 540, 541E (Tt) is at DLC2 which is underneath steering column. http://meisners.net/camry/Links/Moto...lectronics.htm After reading the article I think the best is by adjust the pressure cable very much like standard transmission. The sure way is hook up to pressure gauge.

Another thing is these trans does have temp sensor inside valves body and it seem to serve purpose during hot condition. Couldn't find much info for cold and normal temp. Would be nice if I can see the logic chart.

After much of the research, I actually found out my t100 TC is not perform correctly. I got very low 0-60 and no lock-up and that causes the gas mileage. Good to know I benefited something

[fenixus]

Thanks Nark

will read through it later, sounds promising

[Nark]

Have you found DLC2? Here the location on Camry, not sure if it same with Solara http://autorepair.about.com/library/...bl622a-lib.htm

I didn't see any on mine dlc1 either (empty slot) and I don't have dlc2...just dlc3. The fm only shown tt pin on the ecm but it seem like a hassle to mess with.

[fenixus]

ah I forgot about this thread LOL

I have seen this round plug somewhere, just not sure if it was on my Toyotas or old recent Buick (or former Pontiac or Ford) I used to have ages ago, will check it out soon

just need to recall what I was supposed to measure ... Tt-E2 (or any other ground) while opening the throttle?

Originally Posted by Nark

Have you found DLC2? Here the location on Camry, not sure if it same with Solara http://autorepair.about.com/library/...bl622a-lib.htm

I didn't see any on mine dlc1 either (empty slot) and I don't have dlc2...just dlc3. The fm only shown tt pin on the ecm but it seem like a hassle to mess with.

[fenixus]

OK, I found DLC2 and unfortunately I again have no Tt pin in this plug (checked both cars) ... my last option is to find it at DLC3 (OBD2 connector) or test it at the ECU ... or I will choose an easy route and when it gets warmer again I will ohm the TPS out again carefully through the whole range (not only the open & closed position).

a serious temperature drop here, for 2 days we will have arctic weather, not helpful in lurking around the car.

[Nark]

Originally Posted by fenixus

OK, I found DLC2 and unfortunately I again have no Tt pin in this plug (checked both cars) ... my last option is to find it at DLC3 (OBD2 connector) or test it at the ECU ... or I will choose an easy route and when it gets warmer again I will ohm the TPS out again carefully through the whole range (not only the open & closed position).

a serious temperature drop here, for 2 days we will have arctic weather, not helpful in lurking around the car.

Yeah, sorry to hear about the weather. Used to station in VA. Hated the rain and cold.