85MM TB to big

The problem I had with mine is that the "countersunk" part on the TPS was big around to seat up inside the TB. The part # that I'm using now is E9EF 9B989 BA. Strangely, for the 1st couple of weeks I had it on I got an occasional code 121, MAFS to TPS circuit problem. After a couple of weeks it went away, & I haven't seen a check engine light since.
 
i never had any such problems with the 75 mm tb
I did check the tp volt-were fine and no check eng light g/l
 
XR7 Dave said:
Key on, engine off, throttle closed, probe the green wire. Should read .92-.97V. You can do it with the TB off, but it has to be plugged in meaning that you ain't goin far with it. :)
Click to expand...

What do you look for if you get zero by probing the green wire.
When setting the TPS.

If you use the red probe,to probe the green wire.
Where do you place the black colored probe?

I get a reading if i use the red probe on the red wire.
And use the black probe on the green wire.
 
Last edited:
Randy N Connie said:
What do you look for if you get zero by probing the green wire.
When setting the TPS.

If you use the red probe,to probe the green wire.
Where do you place the black colored probe?

I get a reading if i use the red probe on the red wire.
And use the black probe on the green wire.
Click to expand...


Well have been going through this quit a bit lately, I think I can shed some light. I usually put the negative (black) probe from the volt meter on any ground source, like the ground from the battery, and then the Red probe, goes to the middle wire, I cant say for sure what color it is. On my 92 it is definitely the middle wire you need to check for voltage. Mike
 
Black to ground, red to green wire on TPS. If you open the throttle with the probe connected it will progress smoothly to about 4.8v at WOT.
 
I have never been able to get a proper reading,I thought it was
my old tester.So I bought a didital read out tester today.

If i Put the black tester lead on the middle wire and red lead
on the red wire of the tps .I will get a reading of 4.70 volts.
Any other way that i have tried i get 0.000 reading.

If i put the red lead to the TPS middle wire and black to ground
i will all ways get zero.on both my testers .

aLL tests with key on.

When i open the throttle the read out gos to zero from the 4.70
somthing volt.
 
Last edited:
I either donot have the right tester again.
or the throttle body is machine wrong.has this
ever happined.I have been tring to fix this
for two to three years.
 
Sorry I was not clear.

Ground the black lead from your meter to the engine directly. Clip it to bare metal somewhere.

Then probe the green wire on the TPS using the red wire on your meter.

You have proven that the TPS is working because you have observed the voltage difference in operation.

What you really need to do though, is verify that the green wire is reading .9-.97v with the throttle closed. Make sure your meter is on the right range. If you set it on millivolts it should read 900-970mV.

With a MP TB it will probably read between .5-.75v instead of .9-.97v. That is what I have observed many times. In those cases it is necessary to drill out the mounting holes in the TPS to allow you to rotate the TPS slightly to obtain proper adjustment.
 
I have been tring to set a BBK 75MM throttle body.
And I have done all that you have listed and it does not work.
I get a reading of 00000

I am waiting on a MP 85MM throttle body to see if i can set it.
 
Last edited:
If you are having problems fully closed, there could be a dead spot in the sensor. Switch to ohms and check for resistance between the red and green wires with the key off. There should be some sort of low continuity between them. If it shows open, you have a dead spot in your tps.

Chris
 
seawalkersee said:
If you are having problems fully closed, there could be a dead spot in the sensor. Switch to ohms and check for resistance between the red and green wires with the key off. There should be some sort of low continuity between them. If it shows open, you have a dead spot in your tps.

Chris
Click to expand...

I can get a reading with this setup.But no reading
with the proper connection of red probe to the
middle wire, & with black meter probe wire to ground.
With key-on

I have used two testers,and one old & one new
throttle position sensor.&twasting with meter set
in mil-v .And every other position just to see.

I don't think after 50+ times tring to probe the middle
wire that it does not make contact.The only way I get
a reading from the middle wire. Is to connect the black
meter probe to the middle wire,And the red probe to
the red wire of the TPS plung-in.And if i remember right,
the meter has to be set on ohms
 
Last edited:
So do you have any voltage with the red lead connected to the red wire and the black lead grounded? I dont think you have a bad connection in the wiring but the sensor might have a bad spot in the potentiometer. It has been known to happen :rolleyes:. You got another one to stick on there? Have you tried to adjust it with the screws out and running? By turning it just to test I mean?

Chris
 
Well today I tossed both meters in the weeds.
And tuned every thing back by ear.Runs ok
again. :)

Now I can start doing some more mods Monday.
Like tring a new 85mm throttle body.So I will
be back Monday ,to ask question on tuning it. :)

Thanks Randy
 
Last edited:
You must log in or register to reply here.
Back
Top