cruiser54

Good point JeepDriver. Here's something else that might help, and needs doing anyway. CRUISER'S MOSTLY RENIX TIPS IMPROVING THE FUEL PUMP GROUND JANUARY 3, 2016 CRUISER54 54 COMMENTS The fuel pump and fuel tank sending unit ground at a sheet metal screw up behind the spare tire on an XJ, and behind the driver’s taillamp on an MJ. Not only is a sheet metal screw a lousy way to ground things, this ground path is long and travels through some connectors that are prone to corrosion and moisture. Locate the black wire on the HARNESS side of the fuel pump/sender 3 wire connector. Remove a 6″ length of the split loom covering. Strip back about 1/2″ of insulation from the BLACK wire. Take your new ground wire, preferably at least 14 gauge and 12 to 18 inches long as needed, strip it about 3/4″, and wrap it around the exposed part of the harness plug wire.Solder the connection. Tape it up and reinstall the split loom covering. At the other end of your new ground wire, add a crimp on eyelet. Attach the eyelet under a bolt that goes directly into the chassis. Be sure to clean the attaching point til shiny and apply OxGard to the contact surfaces.

C.R.A.P. Chinese Replacement Auto Parts

Yes. Possible vacuum leak. Also possible you bumped an already poor connection in the engine bay. Have you visited my website and completed tips 1 through 5? If not, get those done first.

The ground there should no be an issue. Good chance you have a faulty alternator.

It's for the ET501 tester to plug in. Pretty much worthless as a diagnostic tool. Or maybe the MS1700 tool. Equally useless.

What a photo!!!!!

Nice job.

You used Dex/Merc fluid?

Need to do Tip 1 also.

Get an ohms reading on the black wire on the ignition control unit. Have you ever refreshed the ICU? Tip 2.

what are the readings at TPS ground to battery ground? Is the big cable attached to the engine and firewall? If so, the paint needs to be cleaned off the firewall and the oil off the engine where it attaches.

There's still a leak somewhere.

I would slow down on the Parts Cannon approach. A TCU certainly would not cause the condition you are describing. Have you completed Tip 5 at www.cruiser54.com? Sounds like a common ground to multiple sensors could be the culprit. And for sure, there is a good ground firewall to engine?

Normal, even though it looks rather primitive.

Let's not jump the gun here. I would first adjust the throttle valve cable. Make sure it has Dex/Merc ATF in it. When is the last time the fluid was changed? What year is the truck? There were different TCUs used over the years. I would bypass the Power/Grandma trans switch. They fail frequently and default to Grandma mode. THE HISTORY OF THE 4.0 BYPASSING THE POWER/COMFORT SWITCH AUGUST 6, 2016 CRUISER54 42 COMMENTS Even though the indicator lights up in your Power/Comfort switch, that does not mean the switch is working and putting the Transmission Control Unit into Power mode. The switches had a high failure rate. Remove and unplug the switch. In the harness are 3 wires. One has a stripe, one is tan, and the other wire is black. Make a 4″ jumper wire with a male spade at each end. Plug one end of the jumper wire in the cavity for the tan wire and the other in the cavity for the striped wire of the harness and you’ll be in permanent Power mode. Stuff the harness back in and reinstall the switch for looks if you want. Make sure the 7.5 amp “Trans” fuse in the fusebox is good. If you happen to have a 91 or 92 XJ/MJ and it has the Power/Comfort switch, just jumper the Tan and Blue wires in the harness plug. NEVER include the black wire when jumpering!!!

Go 4.10s. You'll be fine

The best thing to do is eliminate the distro block. Connect the front lines together. Run a line to the rear with an adjustable brake valve. The distro block has small orifices in it which limit front braking.

I know. I used to work for them. My friend's dad invented the original Torsen. Originally called the Dual Drive Differential. They made me a pair for my Nissan Patrol about 40 years ago. My demo vehicle for the diffs was a 76 Cherokee Chief with Quadratrac. I'd like to see a pic because they started using the Torsen name on other diffs as years went by.

We'll see. Torsion isn't a differential either.

What is a Torgusen? Got a pic?

Could there be a mix-up in the wiring there?