Q45tech Throttle Position Sensor question.

[Need4Speed]

Dennis, I have been going thru all transmission diagnosis procedures to check my transmission out thoroughly and I may have a found a problem.

Under Electrical Components Inspection, AT-67, My Throttle Position Sensor is only showing 3.04v at full pedal depresion. FSM states approx. 4.0v at full pedal depression. Is mine within range or do I ned to investigate further.

-Andy

[Q45tech]

Closed should be 0.4-0.45 voltsWot should be at least 4.0 volts ~~ 4.4 volts is nicer.Seem to remember the ecu needs at least 3.8 volts to reconize WOT.

As read on the Consult

[Need4Speed]

Could this TPS problem be part of my transmission not shifting to 3 or 4 manually or in D?

-Andy

[Need4Speed]

BTW, so far everythig else eletrically related to the AT is checking out OK. Inhibitor Switch circuts are OK so far....I have to check the actual Inhibitor switch itself yet.

What is the posibility of a Shift Solenoid A or B failure causing the problem....and how hard are these solenoids to get to.

-Andy

[HeavyDuty]

This may be totally obvious, but you can adjust your TPS. Look at the set screws on it & adjust it until the voltage reads within spec.

Mine has yet to be done, along with a CAS dial in, but my MAF is already regrounded & it alone made a huge difference.

Yes, solenoids can fail.

[Need4Speed]

Hmmmm.....I forgot about that....thanks for the reminder!

Still trying (hoping is more like it) that I can pin my transmission problems on some cheaper electrical AT component rather than a total R&R!

-Andy

[Q451990]

Has the TPS been adjusted in the past? If not, I wouldn't think adjustment would be necessary. They seem to be fairly bulletproof...

Heath

[Need4Speed]

I have not adjusted it....someone in the past 182k could have though....

-Andy

[Q45tech]

Well if you are measuring correctly it [TPS] is set wrong. First things first get the sensor corrrect via the Consult........then worry about transmission internals.

TPS can develop wear spots but usually at cruise voltage.

[Need4Speed]

Thanks, Dennis.

Now I have to see if I can find a dealer closer than 150 miles that has a Consult......

-Andy

[Q45tech]

The closest Nissan dealer is 150 miles away?

[Need4Speed]

I was speaking of the closest Infiniti dealer, there is a Nissan dealer in town....Just not sure if I want to go back there...........

Past expeince there has been way less than great. But I suppose I could suck-it-up for a consult diagnosis.....

-Andy

[elwesso]

Dennis, cant you just read the voltage with a VOM on the car.....?? I mgiht wanna try that (more free stuff)

[HeavyDuty]

DCB response:

Yes.

[Q45tech]

The voltage feeds an A to D in the ecu so I like to see what the ecu actual thinks the sensor is reading.

You could ASSUME that the output [of TPS] voltage is translated correctly.VOM vary in accuracy and operator knowledge.........what counts is what the ecu says it sees.