jtrask

The PO on my 87 4.0/4wd cut the TPS engine side 3 wire connector out and taped the wires together.

How do I probe the wires to see if the TPS needs to be adjusted or replaced since the wires cannot be back probed?

What is the best way to connect the wires to the 3 wire pigtail I picked up at the bone yard?

Thanks!

VTJeep

i wish i knew more about the older xj's.... i guess youve got the odb1 setup, so you can still pull codes? (idk) but either way, if you CAN plug in a good code reader/diagnostic tool, you can check to see what % of throttle the TPS is reading. mine was bad ('99) and with the code reader on it, we found the TPS only reading 1-3% throttle, no matter if it was floored or at idle. so a new OEM one and she reads very acurately.

jtrask

It's an 87 Renix, so as I understand it... no codes.

Can I stick sewing pins in the tape and connect the probes to that for a read?

I really don't want to start replacing parts unless they are bad.

Also, is there a better way to connect the wires than tape? If I'm going to bother with it, I'd just as soon do it right the first time.

It's running rich and all the plugs are firing, so I'm guessing it's just an adjustment that's needed. Want this on the road asap though... seeing it in the driveway, but not driving it is killing me!

Thanks!
Jan

89Laredo

Go get another tps connector, from the junkyard if you can (both sides)
Solder and heatshrink.
Sewing needles and alligator clip "jumpers" work, thats what i used.
Push the needles into the back of the connector, attach one end of each jumper to teh needles, attach other ends to the probes from the multimeter.

cruiser54

This^^^. Do you have my TPS instructions?

jtrask

cruiser 54- I have your instructions for testing from another thread on this site.

The PO has bypassed the engine side TPS connector. The wires are twisted and wrapped. I was hoping to test the current TPS before buying a new one.

Chasing electrical demons is not my strong suit. Is there a way to test the current wrapped connection to see if the TPS is responsible for the rich run before I just throw a new TPS at the mix. Would sticking sewing pins in the wrapped connection give me a decent read?

Or do I need to do as 89Laredo suggested and solder/heat shrink a new TPS in regardless?

Thanks for the feedback!

Jan

5-90

The connector is a standard three-pole Delphi Weatherpack, you should be able to fine a pigtailed version in the "HELP!" section at the local.

You can't backprobe through tape easily - strip the tape off and clean a spot on the exposed terminal, clip the leads on. Be careful they don't get shorted to each other or to ground!

If you use a pigtailed connector, I tend to favour the use of heat-shrinkable butt splices (you crimp them on, then shrink them down to seal.) You can also get unassembled Weatherpack connectors and do it like OEM yourself - it does require a certain crimper to do a good job (and a bit of technique,) but it's easy enough to do. I can send you an instruction sheet on Weatherpack terminal assembly if you like - it's for a fuse holder I carry, but the principles are the same (PM me your email address.)

cruiser54

Yes. Do what Jon suggests. You can test the TPS beforehand and that is a good idea. If it were me, I would replace the TPS regardless.