modenaf1

iTrader: (3)

Hey guys, I have a calibration question for my Throttle Position Sensor.

At wide open throttle, my TPS only reads 90 percent throttle. Now, normally I would calibrate it, but one issue I have is that it seems to be calibrated perfectly on the other end.

With my foot totally off it, it reads 0 percent, and if i barely touch it it reads 2 or 3 percent. If I adjust this so it really reads 100 percent at wide open throttle, then when my foot is completely off, it will probably read 10 percent when it should read 0.


Any ideas on how to calibrate this or do I probably need a new TPS?

pmohr

iTrader: (26)

Pull the TB and adjust it off the car. It's possible you can get it set perfectly, damn thing is twitchy as hell to set properly. As I'm sure you know, the tiniest movement will change the reading.

Personally when I adjusted my TPS to be perfect at WOT, I had some slight idling issues and sometimes the trans seemed to get confused (back when I was an auto). Adjust it to be perfect at idle and everything was perfect, noticed no difference at WOT.

Do you think you have a problem with it only reading 90% at WOT, or is it a standalone 'issue' you were just looking to fix?

AndrewR2442

iTrader: (1)

to calibrate it properly you need to use this TSB. http://www.lyberty.com/car/Maxima_A3...NTB99-053b.pdf

I picked up a set of feeler gauges for about 4 bucks at autozone. Its just a few thin strips of metal at different mm thickness.

pmohr

iTrader: (26)

...what TSB?

Ah, NTB99-053b.

Feeler gauges never worked for me, I find just using a multimeter and bumping the TPS to be the easiest way

modenaf1

iTrader: (3)

It is just a standalone "issue" I was just looking to fix. I don't think the car is kicking back into open loop mode though when I floorboard it because it doesn't think I am flooring it. I am not too sure, it is somewhat tough to go wide open throttle in a 200hp car and look over at fine print on a slowly updating laptop screen with fine print in the passengers seat.


One thing i wondered though, is there is a stop screw for the throttle itself, not the entire sensor. Is it possible that my sensor is spot on and my throttle is only opening 90 percent? It is somewhat difficult to tell. I don't want to adjust that screw and end up having my throttle plate go too far and end up restricting flow.

EDIT: Nevermind that last bit, I thought that was what stopped it at WOT, but thats the idle stop screw that should absolutely not be messed with according to the FSM.

njmaxseltd

iTrader: (19)

Does your trans downshift and hold the gear to almost red line?
If it does then the ecu and tcu are aware that your WOT.

chillin014

iTrader: (67)

what software are you using? My VAFC only reads like 97 percent since I've messed with the tps

modenaf1

iTrader: (3)

My trans only shifts when I tell it too.

I am using an ELM327 OBD2 scanner with the 7 day trial version of OBD 2007.

It seems like the range of the TPS is only 90 percent or so, so whatever resistor or whatever is in there, it must be wearing out. I would not be surprised if this is the original TPS that has seen 180,000 miles.

The Infiniti I30 that I got my tilting headrests and auto dim mirror from is still in the junkyard and it only has like 80,000 miles on it, so I might go pull that TPS and see if it makes a difference.


The other night I adjusted mine so it would go to 100 percent when I floored it, and I don't know if it was psychological or not but I could swear I felt a difference. Only problem is, it thought I was pushing the gas like 10 or 11 percent when I was completely off, thus the IACV was wide open and the injectors were still running, so I just put it back to 0 at idle and 90 at wot.

MorpheusZero

iTrader: (10)

About a year ago both my buddy with a '97 and I hooked a scanner up to our cars, we both read TP 92% under WOT.

I think it's pretty normal. Since you're a 5 speed, the most important part is that the throttle is actually open 100% and is not restricting flow, your IM is at 1 bar (no vacuum) and the MAF is reading plenty of CFM.

franck0011

yes i think that is normal ... beacause if you play with the adjustement... ?*$/%$"%&?)&*%$/" its pain in the ***... the transmission slip or shift too freakin hard... for me ive adjusted the CTPS to 0.48 volts and with obd2 scanner im like 90-92% too a WOT

TravisCadello

so 90% WOT on a 5speed 00 maxima normal?

pmohr

iTrader: (26)

You're in the wrong subforum, but the FSM specs 0-80% as normal.

6cyl-97maxima

My 97 Max reads 90% at WOT. I think this is normal.

dwapenyi

iTrader: (3)

Physically look at it. Remove all the air filter stuff so u can see the TB clearly. Have someone floor the accelerator pedal. If when the pedal is floored the TB is as wide open as it can go, then u are good.....that phyiscal WOT may correspond to the TPS 90%