tps testing

can anyone confirm that it is OK to remove both (auto trans) TPS connectors (at same time or independent of each other) while the jeep is idling in park? i want to do this to test and see if the tps is causing my high idle. i am pretty sure it is b/c the shifting is different too. IAC motor is new and didnt fix anything.

also, i need to confirm that it is ok to splice a ground from the tps to the manifold or the firewall. and just to be sure, what pin on the flat connector is the ground? and what pin on the square connector.

thanks

Ok, first, yes you can disconnect the TPS any way you like. Second I would not mess with the ground. Chiltons describes how to check your tps. If you do it by the book you'll know if the TPS is bad or if you have a faulty wire. I had a high idle problem and it was due to a bad connection to the tps. I pulled the connector appart, cleaned it very well and lubed it with dilectric grease and haven't had any more problems.

everyone talks about cleaning these electrical connectors for the TPS and IAC....C101 connector...etc. what is the best way to clean these connectors?

You can use an aerosol electrical cleaner that you can find at Home Depot or NAPA. I don't think there's an easy way to clean the C101. The grease is really stiff and sticky.

Where is the C101 connnector on an ABS XJ? There is nothing above the master cylinder on the firewall...

Below the master cylinder. I know that's a really stupid place for it. That's why it's called the "evil connector"

I have heard of adding an extra ground wire to the TPS. It's spliced into the CPS ground, and connected to an engine bolt. If you have good continuity on the original ground wire, this shouldn't be necessary, though. I think most "bad" grounds can be traced to bad connectors.....

Neil said:

Below the master cylinder. I know that's a really stupid place for it. That's why it's called the "evil connector"

Click to expand...

We're talking about two different connectors here. All XJ's have the big inaccessible connector below the master cylinder, through which all the chassis wiring is routed to the fuse box, etc. But early 4.0's also have a big connector above the master cylinder, through which all Fuel injection functions are passed. This connector doesn't actually psss through the bulkhead, but just joins two sections of harness. I think they dropped this connector somewhere between 88 and 89. All 87's have it. My 89 did not.

There may be some confusion in the numbers, because they may renumber them when the wiring is changed. On the 95, at least, the two-part "evil" connector that hides beneath the master cylinder is C-108, and C-101 is now the connector to the ECU itself.

Thanks for the clarification. I apologize for the misinformation.