cruiser54

All symptoms of a bad O2 sensor. Use NTK. Not Bosch.

So my hopes are shot.....

More info please.

TJ. What I have..............

More like 350,000 miles.......

Bendix and Renix are one and the same. Renix was a joint venture of RENault and bendIX That said, the ground refreshing and upgrades apply to your rig.

ZJ or TJ Canyon wheels?

Add-on cruise control?

Renix Ground Refreshing The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, failed emission tests, and wasted money replacing components unnecessarily. The components grounding at the dipstick tube stud are: Distributor Sync Sensor, TCU main ground, TCU “Shift Point Logic”, Ignition control Module, Injectors, ECU main ground which other engine sensors ground through, Oxygen sensor, Knock Sensor, Cruise Control, and Transmission Sync signal. All extremely important stuff. The factory was aware of the issues with this ground point and addressed it by suggesting the following: Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Must be clean, shiny and free of any oil, grease, or paint. Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Reinstall all the wires to the stud and tighten the nut down securely. While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, and reattach securely. Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for it’s intended use and subject to corrosion and poor connections at each end. First off, remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Reattach securely. Remove the other end of the cable from the rear of the head using a 3’4” socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely. A suggestion regarding the braided cable: I prefer to add a #4 Gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18” long with a 3/8” lug on each end works great and you can get one at any parts store already made up. Napa has them as part number 781116. A further improvement to the grounding system can be made using a #4 cable, about 10” long with 3/8” terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. Napa part number 781115. For those of us with Comanches, it’s very important to remove the driver’s side taillamp assembly to access the ground for the fuel pump. Remove the screw holding the black ground wire. Scrape the paint from the body and corrosion from the wire terminal. Reattach securely. If you want to upgrade your grounds and battery cables in general, contact Jon at www.kelleyswip.com. He makes an incredible cable upgrade for a very reasonable price. Revised 03-04-2013

Change fuel filter. Test fuel pressure. Index the distributor.

Gonna need to lengthen the MAP wires I bet.

How does that MAP sensor mount Don?

I remove the throttle body and tap the lower hole on it to 1/8" NPT thread and plug it. I move the IAT to the upper half of the air cleaner. I then install a fitting in the intake manifold that will accomadate a hose/pipe to run to the MAP sensor.

I had something like that on a Miata with a supercharger. Triggered by knock sensor and retarded the timing via the CPS circuit.

You beat me to it!!!

I've got a set I pulled off a 90 XJ I parted out. Never got around to putting them on.

I would say any column from an XJ or Mj up until Chrysler started using their own columns.

Yeah. Those HOs were quite troublesome......

The CPS didn't generate a strong enough signal for the ECU. 1) The CPS was too far from the flywheel. The sensor in the bypass kit had a slotted upper hole. See my Tip 7. 2) There was too mush resistance in the stock harness and especially the C101 connector which reduced the signal the ECU got from the CPS. See my Tips 2 and 27.

Waiting for a response from my buddy at the dealer.

I think they're 1/4" bolts. The top photo is mine. the lower one isn't. Hole facing the firewall.

Here's what probably happened. Your Jeep had the CPS bypass done at the dealer. The tech was supposed to clip off the original harness connector for the CPS and tape it back. He didn't.

Somewhat true...but it's not quite that cut and dry. If you do the basic brake force math using the factory disc brakes front and rear with a 1" master cylinder bore and 60lbs of input pressure you end up with a bit over 4900lbs of front braking force and a bit over 2800lbs of rear braking force (with ZJ rear disc setup). which gives a 61.5% braking force bias. and a total braking force of 7700lbs. Just increasing the rotors in diameter by 1" front and rear (12.02 front and 12.21 rear) with the same braking force input you end up with just shy of 5500lbs of braking force front and a hair over 3100lbs of braking force rear - a total of 8600lbs of braking force . All of that from only a 1/2" increase in that lever arm radius at each end, and without any change in the brake line pressure, and as a result, brake pedal feel or travel. On top of that better thermal management you brought up - which is never a downside. going to a larger bore master cylinder actually reduces brake line pressure, and as a result brake force, at the same input force. Smaller, the exact opposite. This will also greatly change the feel of the brakes and the brake pedal travel. It's not something I would do lightly to improve braking power personally, but is an option. Generally, the change in master cylinder size should coincide with a change to caliper piston diameters, which also greatly effect brake force in relation to said master bore size. etc etc yadda yadda. I learned a lot about brake math and setups after swapping C5 corvette brakes on to my Isuzu. I went this route, in this order. Somewhat scientific and logical. 88 XJ rear discs off a Grand. Nice. 90 MJ 95 to 96 booster and master keeping rear drum brakes. Holy mackereel!! WJ booster/master on the XJ that already the rear disc conversion. Very nice!!! rear discs and WJ booster are next on my list. There are 5 ZJ's with rear discs and 2 WJ's at the nearby pick and pull. If everything goes right, I plan on grabbing most of the parts I need to do the conversions and re-doing my front brakes and bleeding the whole system. My brakes right now work well enough, but they don't inspire confidence. I plan on getting the main brackets for the rear disc and using rebuild calipers and new rotors. Anything from the booster side I should grab? ZJ or WJ prop valve? ZJ prop valve guts.

Can't find the whole TSB with the procedure?

Somewhat true...but it's not quite that cut and dry. If you do the basic brake force math using the factory disc brakes front and rear with a 1" master cylinder bore and 60lbs of input pressure you end up with a bit over 4900lbs of front braking force and a bit over 2800lbs of rear braking force (with ZJ rear disc setup). which gives a 61.5% braking force bias. and a total braking force of 7700lbs. Just increasing the rotors in diameter by 1" front and rear (12.02 front and 12.21 rear) with the same braking force input you end up with just shy of 5500lbs of braking force front and a hair over 3100lbs of braking force rear - a total of 8600lbs of braking force . All of that from only a 1/2" increase in that lever arm radius at each end, and without any change in the brake line pressure, and as a result, brake pedal feel or travel. On top of that better thermal management you brought up - which is never a downside. going to a larger bore master cylinder actually reduces brake line pressure, and as a result brake force, at the same input force. Smaller, the exact opposite. This will also greatly change the feel of the brakes and the brake pedal travel. It's not something I would do lightly to improve braking power personally, but is an option. Generally, the change in master cylinder size should coincide with a change to caliper piston diameters, which also greatly effect brake force in relation to said master bore size. etc etc yadda yadda. I learned a lot about brake math and setups after swapping C5 corvette brakes on to my Isuzu. I went this route, in this order. Somewhat scientific and logical. 88 XJ rear discs off a Grand. Nice. 90 MJ 95 to 96 booster and master keeping rear drum brakes. Holy mackereel!! WJ booster/master on the XJ that already the rear disc conversion. Very nice!!!