cruiser54

Here's something to help wit diagnosing oil leaks yourself: 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

Nah. Do the stuff suggested. You have a meter, right? You're gonna need one to adjust a new TPS if it gets to that.

Could be a leaky valve cover?

Used only. Use a light sealer on it like GasgaCinch.

Have you cleaned the C101 and done the sensor ground test? Napa TPS is okay. But, remember you need to adjust it using the instructions for the flat 3 wire connector.

Get that MAP sensor line in tip-top shape first thing.

Seriously? How much more drag can they add to our brick shaped vehicles? That would depend on the size of the mirror, wouldn't it. Towing an 8-and-a-half-foot-wide trailer (the legal limit), you need big mirrors mounted wide. Besides the added drag (which, despite the clown comments above, is quite significant), such wide mirrors are beyond inconvenient when not towing. They are at risk of being broken, their appearance is aesthetically displeasing, plus as I mentioned already they cost in extra gasoline consumed. As an aside comment, the squarish lines of the Comanche contribute far less to aerodynamic drag than does the open bed. Drags results less from the shape of the front of a vehicle punching a hole through the wind, but more from the shape thats helps close that hole in the wind behind it. So, I'm betting you have a tonneau cover of some sort on your Comanche? Fiberglass or fabric? Where did you get it? I've been unable to find either one.

With the engine running, 31 PSI at idle, jumping to 39 PSI when you unplug the vacuum line from the fuel pressure regulator.

And, if it's an 87 or 88, do the C101 connector refreshing. Renix Jeep C101 Connector Refreshing The C101 connector on 1987 and 1988 Renix Jeeps was a source of electrical resistance when the vehicles were new. So much so that the factory eliminated this connector in the 1989 and 1990 models. The factory recommended cleaning this connector to insure the proper voltage and ground signals between the ECU and the fuel injection sensors. We can only imagine how this connector has become a larger source of voltage loss and increased resistance over a period of almost 25 years. The C101 connector needs to be cleaned at least once in the lifetime of your vehicle. Chances are it’s never been done before. Almost every critical signal between the engine sensors, injectors, ECU, and some to the TCU, travel this path through the C101 connector. The C101 connector is located on the driver’s side firewall above and behind the brake booster. It is held together with a single bolt in it’s center. To get the connectors apart, simply remove the ¼” bolt and pull the halves apart. You will find the connector is packed with a black tar like substance which has hardened over time. Take a pocket screwdriver or the like and scrape out all the tar crap you can. Follow up by spraying out both connector halves with brake cleaner and then swabbing out the remainder of the tar. Repeat this procedure until the tar is totally removed. This may require 3 or more repetitions. Wipe out the connectors after spraying with a soft cloth. If you have a small pick or dental tool, tweak the female connectors on the one side so they grab the pins on the opposite side a bit tighter before bolting both halves back together. Revised 03-02-2013

When dealing with TPS issues on a Renix, always do a sensor ground test first. Cruiser’s Renix Sensor Ground Test This sensor ground circuit affects the CTS, TPS, IAT, MAP, ECU and diagnostic connector grounds. It’s very important and not something to overlook in diagnosing your Renix Jeep as it is common for the harnesses to have poor crimps causing poor grounds. If any or all of the sensors do not have a good ground, the signal the ECU receives from these sensors is inaccurate. Set your meter to measure Ohms. Be sure the key is in the OFF position. 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 runs parallel to the valve cover and also near the MAP sensor mounted on the firewall. If you have an 87 or 88 with the C101 connector mounted on the firewall above the brake booster, wiggle it, too. You want to see as close to 0 ohms of resistance as possible. And when wiggling the harnesses/connectors the resistance value should stay low. If there is a variance in the values when wiggling the wires, you have a poor crimp/connection in the wiring harness or a poor ground at the engine dipstick tube stud. On 87 and 88 models, you could have a poor connection at the C101 connector as well. Revised 06/12/2012

Seriously? How much more drag can they add to our brick shaped vehicles?

Did you bust the line going from the throttle body to the MAP sensor in the process of doing the injector swap?

Here's the info garnered from the NAXJA thread. http://www.naxja.org/forum/showthread.php?t=1107182

Nice attitude? Look at the smart @$$ link that helpful person posted. He was truthful, provided good links, and you didn't get a bull$#!& response from someone with false info. What's the problem?

Nice attitude. Did you post this question on one or more of the other forums also?

Might not be the pump itself, but the hose inside the tank that goes to the pump.

That first link is too cool!!!!!!

The thermal sensor triggers a relay. More than likely the relay is stuck Isn't that relay right there on the driver side inner fender?.

Not on my 1990. Was on my 1986 though. My 90 does pop off after setting it as have other MJs I've had. I had a total of 13 demos at the dealership which I drove for 7500 miles max, and then the 86 and now the 90 which I own. Both 86 and 90 had the same issue.

It MIGHT have been more than 1986 come to think of it. I should run the VIN on my 90 at Chryco's website.

go to a junkyard and take the time to pull one. it's going to be less of a headache. And do the FtPierceCracker fix on it.

Do you have the original Renix type injectors? Ever replaced the oxygen sensor? Does it idle good?

That's EXACTLY what Eagle is trying to tell you.........

Not necessarily ENOUGH fuel pressure. The line from the throttle body to the firewall is for the MAP sensor and should be checked. The IAC is NOT a sensor, but an actuator.

Clean all of the shaft you can see with fine steel wool or the like. Use lots of penetrating oil. Get 2 shim shingles and tap one up under each side of the NSS carefylly.