cruiser54

Then do a good ground refreshing and upgrade your cables per my write-up in the link in my signature.

Used electric fan? Oughta upgrade your cables before doing the alternator though. www.kelleyswip.cm

Do a drain and fill. Test the TPS on the trans side. Refresh the trans connectors.

See post #3, with photo, in the link below. http://www.cherokeeforum.com/f51/cruiser54s-mostly-renix-tips-153657/

NEVER a bad idea to check those bolts.

I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF. Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking. Many mechanics, friends, people on Jeep forums who can’t see your Jeep from where they’re at, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it? A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat. Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons. First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill". Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first. Revised 02-26-2013

You gonna put this as a write-up somewhere?

Look at your ignition switch. Tends to burn at one terminal. The one that affects turn signals, blower motor and a few other things.

Excellent idea bTW. An issue they had in those years was they used British cylinders and filled them with Dot 3 fluid which wasn't compatible. So, the fluid would eat the seals, we would replace the cylinders, and they would fail again. Reason being that an abrasive crud stayed in the original flexible line. Only way to get rid of the issue was replace both cylinders and the line.

What's taking so long? It's been a year. LOL

Check the ISC. Idle Speed Controller. Deal on the throttle body with wires going to it. Has gears in it to adjust idle speed. They wear out. MAP sensors usually cause an overly rich condition and stalling.

Click on the link in my signature and start with Renix Ground Refreshing, then, Connector and Relay Refreshing, The Instrument Panel Ground upgrade should also be considered. Welcome back!!

No I don't. I'll poke around. I was hoping he would show up in this thread.

ftpiercecracker did a real nice write-up on fixing the PB assy.

No. The problem is that the vent glass doesn't have a full frame, so where the frame ends there's a small "step" from the metal to the glass, and the rubber gasket couldn't be molded closely enough to properly seal that point. That's where they leaked. If Hornbrod or anyone has one that DOESN'T leak there, consider it a major miracle. YES. The factory put out a bulletin to replace the wing windows with fixed glass if customers complained about it. It was that big of a problem.

Yes. But the factory has you adjusting the TPS on the Trans side connector. No bueno unless you're troubleshooting a trans/shifting issue. Use the instructions below: 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: With the Key OFF, and 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. Wiggle the wiring harness where it parallels the valve cover and also over near the MAP sensor on the firewall. If you see more than 1 ohm of resistance, or fluctuation in your ohms reading, 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 only a flat three-wire TPS mounted on the throttle body and it provides data input to the ECU. It 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. Loosen both T-20 Torx screws attaching the TPS to the throttle body and rotate the TPS until you have achieved your desired output voltage. Tighten the screws carefully while watching to see that your output voltage remains where it is supposed to be. If you can't achieve the correct output voltage, replace the TPS and start over. Sometimes, after adjusting your TPS the way outlined above, you may experience a high idle upon starting. If that happens, shut the engine off and reconnect your probes to B and C. Start the engine and while watching your meter, turn the TPS clockwise until the idle drops to normal and then rotate it back counterclockwise to your desired output voltage. 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, as outlined above—FOR ALL 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. THIS SQUARE FOUR WIRE CONNECTOR IS USED FOR TRANSMISSION/SHIFTING RELATED ISSUES ONLY. 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. FOR AUTOMATIC TRANSMISSION RELATED ISSUES: Check the square four-wire connector side of the TPS. If you have ENGINE ISSUES check the flat 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. Revised 09-22-2012

Improving the Instrument Panel Ground The ground point for the complete instrument cluster on your XJ or MJ is located up under the driver’s side dash. If you lay on your back and look up under there with a flashlight, without wearing a hat, you will see a black wire attached to a shiny piece of metal almost directly above the hood release knob. The screw will have either a ¼” or 5/16” head on it. This ground point is responsible for handling the ground circuit for the following items: Dome lamps, Seatbelt and key warning, trans comfort switch, wiper switch, headlamp switch and delay module, fog lamp switch, cargo lamp switch, all instrument panel grounds and illumination, power windows and door locks, cruise control dump valve, and a few more things. The problem is that where the ground point is located does not have a good contact with the chassis where the ground should be. The solution is simple. Make up a jumper wire with #10 gauge wire about 10” long. On one end, crimp on a ¼” round wire terminal. On the other end, crimp on a 3/8” round wire terminal. Remove the screw from the existing ground wire and attach the small terminal of your jumper so that the original wire and your new jumper share the same attaching point, one over the other. Look above the driver’s side plastic kick panel just forward of the top of the hood release knob. You will see an 8mm stud there. Attach the large terminal end there with a washer and nut over it tightened securely. **Special note for Comanche owners: Make your jumper wire 12” long and attach it on the driver’s side kick panel close to the fusebox on the 8mm stud.** Revised 11-29-2011

The senders and switches look a bit different. I bagged a bunch at the JY and compared them side by side. TS219 on RockAuto. http://www.rockauto.com/catalog/moreinfo.php?pk=40492&cc=1179929

Check to be sure your intake manifold bolts aren't loose. A vacuum leak can be found by spraying throttle body cleaner around suspect areas with the engine at an idle. Cleaning the TPS usually spells sudden death for it bTW. Did you get the TPS lever back on the correct side of the linkage?

Replace it.

And reduced backpressure in an exhaust = loss of torque at low and mid-range RPMs. Since I never operate a 4.0 liter higher than 2500 RPM (and rarely even that high) I'll take the torque that I use every day over the 5000 RPM horsepower that I'll never use -- ever. Absolutely! That is why I don't waste my money on larger or "free flowing" exhaust systems. Replacing defective exhaust components is one thing, but adding headers and 3" pipes are just a waste of money to me. I am a low rpm jeep driver. A certain amount of back pressure is required. (or should I say desired) Now, if that dimple was put there solely to cause more back pressure than the optimum, as cruiser is suggesting, so it will heat up the converter, then I would do that mod. Not many dyno experiment results available to go by, so much of this talk doesn't really mean squat. We can only generalize. If anyone knows of some dyno results, please share. Agreed, was just trying to point out that there is a point of diminishing return when opening up an exhaust system. I was clarifying (or attempting to) my earlier statement. Again, thanks for the tip that I am certainly going to use. I also notice another dimple where the pipe crosses over the cross member. Do you know of any aftermarket down pipes for sale without those dimples? Muffler shops are 300 mile away round trip for me. I don't know of any off the shelf pieces but I heard they exist. I appreciate your clarification on the "point of diminishing return".

Well stated. We're talking about a dimple in the system right at the exit of the exhaust manifold. Just removing that. We're not talking about putting a 4" free-flow system on full length.

Yes. Elimination of the crush works great. I have done that mod twice all on it's own with no other mods at the same time and experienced better throttle response and acceleration, just like my buddy at JeepTech told me I could expect.

Lots of time and money.

Here's where "old wive's tales" come into play and are usually propogated by those who have never done the mod. . This lower back pressure deal is an absolute crock. That's something that applies to 2 stroke engines mostly anyway. I will now add that I was advised to do this mod by a Jeep engineer who worked on the 4.0 project. He's the one who told me about "why" the crush is there. He told me I would feel a "seat of the pants" difference in throttle response and power. He was right. Don't let the "old wives tales" keep you from enjoying the benefits of this mod.