• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

TPS Question

T

The Lure Washer

NAXJA Forum User
Location
Bristol, CT
When testing the TPS what should I be getting as for an output voltage reading. I know that the input voltage should be aprox. 5 volts. My read as 4.66 volts. You are supposed to devide output by input voltage. Now am I supposed to get my reading to 100% Thats the part I dont Understand. Can Someone help because I think that may be the reason why 90' is running so rich.
 
winterbeater said:
To answer your original question - the 2000 FSM says 5.0V in, 4.49 out at tull throttle, 0.26 at idle. Probably not your problem.
Click to expand...
The 2000 model is not the same as the renix era. To the OP, auto or manual? The procedure is different.
 
Or:
[DELETED BY ADMINISTRATOR]

If you're failing smog try the following:

  • Buy a NEW gas cap (I know it sounds too simple but I've been told this by more than one smogger and it works, sometimes)
  • Check and replace as necessary ALL vacuum lines.
  • Change your oil, air filter (again, too simple)
  • As in the first link, check your Coolant Temp Sensor, the one in the lower part of the block.
  • Make sure you are getting air thru the CCV valve. Make sure it's not kinked and the grommets, front and rear on the valve cover are in good shape. Blow it out with compressed air or replace.
  • Run a can of G2P (Guaranteed 2 Pass) through the fuel system (follow the instructions on the can).
  • Take it in after a good highway speed run at operating temp 200+.
  • New (hotter) plugs. Nothing fancy, Champion Truck Plugs.
 
Last edited by a moderator:
For a RENIX, the input voltage is optimum at 5.0V. However, my MJ has varied from one test to another from 4.66 to 4.85V. Given the grounds and age of the system, this is not unusual.

That said, if you have an automatic, you are supposed to multiply whatever output voltage you have by .830.

So, with an output of 4.66V, you get

4.66 * .830 = 3.87V

If you futz around with the TPS enough, you'll get there. I should mention that the TPS for the automatic only has a limited adjustment range, so if you get something like .2V you're not doing it right. Mine had a max of 4.2 and min of 3.5 when I was adjusting it last Saturday.
 
For an Automatic:

Everyone says that the output on the TCU side of the TPS should be approx 82 or 83% (Its different everywhere you read it seems) of the input voltage.

In my 1990 FSM, it says the the input voltage should be approx 5 volts. If you have approx. 5v (which i would say would be anything from 4.6v to 5v), then the output voltage should be 4.15 volts. It says nothing about adjusting the TPS to a percentage of the input voltage.

I have always adjusted my TPS to be 83% of the input voltage (which usually would be about 3.85 volts).
The last time i adjusted it (about a week ago) i followed my FSM's procedure and adjusted it to 4.15 volts.
The Jeep seems to be a little more peppier, and the shifts are smoother. Other than that i can say that there is no other difference so far.
 
You must log in or register to reply here.

Similar threads

A
Renix TPS nightmare
Replies
19
Views
3K
Saudade
Saudade
89Mock
Gauge Cluster Swap: Mechanical to electric speedometer
Replies
3
Views
3K
kastein
kastein
C
'98 XJ p0123 help, TPS high voltage
Replies
18
Views
3K
Tim_MN
Tim_MN
L
1989 Jeep Cherokee TPS sensor voltage issue
Replies
5
Views
1K
Landon18
L
P
98 XJ p0700, p0122
Replies
9
Views
1K
Professor_brap
P
Back
Top