92 Q45 TPS Problem...??

[jayhotdaynot]

(also Posted in online mechanic...)Hey Guys , i have a 92 Q45 with out traction control.. I resently changed injctors because she was missfireing and giving code 51(i think) open injector... Replaced the injector, and drove the car.. the check light was off but the car (that has 2nd gear start), just didnt want to shift out of 2nd untill at high rpms then it would shift to like 4th.. then the check engine lite came on.. i ran back to the shop and the code said Throttle position sensor..I did search and hav seen some posts on tps.. but none of them came to a conclusion(as in fix it by doing etc.. or change that crap now).. im gonna check the ohms on it.. but its obvious that theres a problem cause its bringing up codes.. No transmission malfunction display(maybe cause the display works when it feels like) soo not 100% sure.. but wen manualy selecting 1 then 2 the car shifts regular.. Please help me out guys thanks

[Infinitiguy19]

When you say the display works when it feels like it, Do you mean light up when it wants too?

Does the screen just stay on the AT-CHECK screen?

Did you adjust the TPS at all?

Did you damage or lossen the connector at all?

Check the current voltage of the TPS while the throttle is closed and make sure its set at .44 volts.

Then make sure the connector is tight.

[jayhotdaynot]

i mean the small display screen that says brake pads low.. and correction it does say transmission malfunction wen i first start it, just noticed it..

didnt adjust the tps at all.. dont kno how to..

theres is a grey connector that is fine, and a black connector that is not soo good but it makes contact..

im getting 0.9 from the bottom 2 ports on the femail side on the grey connector.. how do i adjust it to get .44v

[Infinitiguy19]

OK so the screen sometimes works?

Go here to see how to properly test and adjust it: http://www.nicoclub.com/articles.php?id=217448

[jayhotdaynot]

Yea the display works at random.. it will be on for 2 weeks and off for 2 weeks come on for a hr and go off.. i hav no idea

well i checked it the tps and it turns out that its not changing voltage at all... its staying at .8- .9 volts even at full throttle... soo i guess thats bad... i called infiniti to see how much one cost and they said $290! soo then i called the junk yard,, they say i have to get the whole throttle body for 100.. soo im gonna do that.. and cross my fingers that that will solve the problem, cause its realy annoying to drive in second gear.. at times it starts out in first(thats kinda fun) but after running out first drops (hard) into second an jus sticks there...

thanks for the help.. ill keep u posted on the turn out

[Q45phill]

mine is actually doing the same exact thing... just drives in 2nd and doesnt shift till around 36-3800 rpm's, so let me know what you come out with and what happens...

[jayhotdaynot]

Update..

Soo i went to the Junk Yard and got a throttle body (q45 are not that easy to find here, especialy when you need a part for yours) Fixed the problem 100%

The TPS was bad.. i would hav just got a tps but the yard didnt want to sell it seperate..

Thanks for the help...

Now what do i do to tweak it for performance?

[Infinitiguy19]

Here is how to remove the dash to get to the lights behind the diagnostic screen:

For a bigger picture go here: http://picasaweb.google.com/lh...tlink

On the old one did you undo the screws that hold it to the TB and turn the TPS in either direction and measure the voltage in each direction?

You have two options ahead of you:

1. Remove the TPS from the throttle body and install it on your car (Check to see that it works first though) (Hope you have some sort of warranty).

This way is better because if you know your throttle body has not been tampered with and your car warms up normally, then all you have to do is install the TPS.

2. Install the Throttle body and assume that the FIC (Fast Idle Cam) has not been tampered with (Those three screws have not been turned).

This is the easiest way because you don't have to worry about fine tuning the TPS if your not doing this in a warm garage after the car is fully warmed up (179*-185* F).

Either choice you take I wish you the best of luck.