birdnerd

So I cleaned my throttle body and I still have a high idel, 1500, I'm going to test/adjust the tps. If I need a new tps can I use the one for an automatic? Mine is a 5spd but there is a 50 dollar price difference. By the way its a 90 4.0 I6 5spd.

cruiser54

This should help you out, and yes an auto TPS is cheaper and works fine.

RENIX TPS ADJUSTMENT
Before attempting to adjust your TPS be sure the throttle body has been recently cleaned.
It's especially important that the edges of the throttle butterfly are free of any carbon build-up.
IMPORTANT NOTE: Using the positive (red) lead of your ohmmeter, probe the B terminal of the flat 3 wire connector
of the TPS . The letters are embossed on the connector itself.
Touch the black lead of your meter to the negative battery post.
If you see more than 1 ohm of resistance some modifications to the sensor ground harness will be
necessary. The harness repair must be performed before proceeding.
I can provide an instruction sheet for that if needed.
MANUAL TRANSMISSION:
RENIX manual transmission equipped XJs have a three-wire TPS mounted on the throttle body.
This manual transmission vehicle TPS provides data input to the ECU. The manual transmission
TPS has three wires in the connector and they're clearly embossed with the letters A,B, and C.
Wire "A" is positive.
Wire "B" is ground.
Key ON, measure voltage from "A" positive to "B" ground by back-probing the connectors..
Note the voltage reading--this is your REFERENCE voltage.
Key ON, back-probe the connector at wires "B" and "C". Measure the voltage. This is your
OUTPUT voltage.
Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For
example: 4.82 volts X .17=.82 volts. Adjust the TPS until you have achieved this percentage. If
you can't achieve the correct output voltage replace the TPS and start over.
AUTOMATIC TRANSMISSION:
RENIX automatic transmission equipped XJs have a TPS with two connectors. There is a flat three-
wire connector, same as the manual transmission vehicles have, and it is tested the same as the
manual transmission equipped vehicles--FOR ENGINE MANAGEMENT RELATED ISSUES.
However, the automatic TPS also has a square four-wire connector clearly embossed with the letters
A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module.
Key ON, measure voltage between "A" positive and "D" ground. Note the voltage. This is your
REFERENCE voltage.
Back-probe the connector at wires "B" and "D". Measure the voltage. This is your OUTPUT
voltage. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage.
For example 4.8 volts X .83=3.98 volts. Adjust the TPS until you have achieved this percentage.
If you can't, replace the TPS and start over.
So, if you have an automatic equipped XJ your TPS has two sides--one side feeds the ECU, and
the other side feeds the TCU. If you have TRANSMISSION issues check the four-wire
connector side of the TPS. If you have ENGINE issues check the three-wire connector side of
the TPS.
For those with a MANUAL TRANSMISSION--the TPS for the manual transmission XJs is
stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced.


birdnerd

I'm new to all thus sensor stuff and all I have is a analog multimeter. Do I need a digital? Can you send me those directions please, I check the ohms, and the sweep is a reverse to the voltage but it says 50

birdnerd

So got a digital multimeter and it is what I'm reading.
.247ohms w/ the meter at 2k
4.82v (a-b) w/ the meter at 20v dc
-0.74v (b-c) w/ the meter at 20v dc

It looks like it is at 15% not 17%. Am I testing everything correctly?

cruiser54

Looks correct. Analog meter is better for the next test and perfectly fine for the first test. With the engine off and the key on probing B and C, rotate the throttle linkage and look to see if there's a bad spot in the TPS.

birdnerd

Well now I'm lost. So no dead spots in the tps. Did the vacum test by covering the opening with a oil can and it choked way out but didn't die. Covered the tb opening with my palm and it died. Swapped the iac and it is still ideling high. What's next to check?

cruiser54

Did you check the sensor grounds as described in the instructions?

Check all your intake manifold fasteners first and be sure none are loose.

After that, spray around all your vac lines and manifold with carb cleaner or the like. When you hit a vac leak, you'll know it.

birdnerd

I figured it out. I pulled the air tube off again and noticed I had about a millimeter gap on the butterfly. Looked over at the stop on the throttle linkage and the previous owner had spun a 10mm nut onto the end of the stop screw. Took the nut off and no gap or scrapping. Fired it up and bam...900rpm. Got to love the little gifts you get when you buy a used jeep. Still doesn't beat when I discovered I had two different types of injectors. I don't think that they knew what they were doing.

cruiser54

I was thinking of that next!! Check your sensor ground circuit and the intake bolts while you're at it though. Glad to hear you found it BTW.

Now you're gonna need to readjust your TPS, too!!!

birdnerd

Will do, after a cup of coffee and a smoke. I looked at the ground on into passenger side of the block and it looked good and the bolts are all solid. I have to drive the XJ from Seattle to Baltimore on two weeks and I'm getting everything squared away before I head out. Just got the door hinges rewelded on Saturday.

cruiser54

Do yourself a favor andremove those grounds, scrape the block clean, polish up the wire terminations and reattach securely.