09-20-2013, 04:54 PM
Join Date: Sep 2008
Location: 3rd rock from sun
Other Noteworthy Threads...
Budget builds: What Junkyard Parts will fit an XJ?
XJ Interior Mods? Whatcha got?
How my XJ gets 25 mpg highway from a few mods
The most awesome Gear Ratio Calculator on the net
Good breakdown of wheel hub components
4.0 engine compatibility
Wheel and Stance Calculator
Originally Posted by dmill89
Yep, here are the 2-letter Jeep model designations if it interests you.
Jeep Model designations:
XJ: 84-01 "Regular" (not Grand) Cherokees.
SJ/FSJ: "Full Sized Jeeps" Wagnoeer (pre-84), Grand Wagoneer, Cherokee (pre-84), J-Series trucks
YJ: 87-95 Wrangler (1st gen)
TJ: 97-06 Wrangler (2nd gen)
JK: 07+ Wrangler (3rd gen)
ZJ: 93-98 Grand Cherokee (1st gen)
WJ: 99-04 Grand Cherokee (2nd gen)
WK: 05-10 Grand Cherokee (3rd gen)
WK2: 11+ Grand Cherokee (4th gen)
KJ: 02-07 Liberty (1st gen)
KK: 08-13 Liberty (2nd gen)
MJ: Comanche (an XJ Cherokee based pickup)
CJ: "Civilian Jeep" pre-wrangler "Jeep Jeeps".
KL: The "new" 2014 Cherokee.
How to test your CPS:
Originally Posted by cherox
What other Jeep wheels will fit your 1997-2001 XJ?
93-98 Grand Cherokee - ZJ = YES
87-2006 Wrangler - YJ TJ LJ = YES
2007-Present Compass/Patriot - MK = YES
02-08 Liberty - KJ KK = YES
99-Present Grand Cherokee - WJ WK WK2 = NO
06-10 Commander - XK = NO
2007-Present Wrangler JK/JKU = NO
14-Present Cherokee - KL = NO
15 Renegade - BU = NO
Originally Posted by CJ7-Tim
The starter engages, but it just won't fire up and run, correct ?
If that is the case, test the CPS.
The most likely cause of it cranks and cranks but won't start up is the Crankshaft Position Sensor (CPS) located on the transmission bell housing. Often this part is also referred to as the CranKshaft Position Sensor (CKP). CPS/CKP failure is very common.The CPS/CKP can stop working with no warning or symptoms and the engine will not run or the engine may randomly stall for no apparent reason. Crank Position Sensors can have intermittent “thermal failure”. This means that the CPS/CKPfails when engine gets hot, but works again when it cools back down.
- Starter cranks and cranks but engine won't start up
- Fuel gauge and voltage gauges may not work or display properly.
- You sometimes will have No Bus displayed on the odometer after 30-60 seconds.
- A failed CPS/CKP may or may not throw a CEL trouble code.
- May have no spark at the spark plugs.
- Fuel pump should run and prime for 3-5 seconds.
If the CPS/CKP is failed sometimes the OBD-II code reader cannot make a connection to the computer or cannot read Check Engine Light/MIL codes because the CPS/CKPhas failed.
Diagnostic steps to confirm the CPS is the cause of your no-start
-You should be able to verify a bad cps, by unplugging it, and turning the ignition key to ON. If the voltage gauge and/or the fuel gauge now displays correctly, replace the CPS.
-Unplugging and reconnecting the CPS sensor where it connect to the main harness near the back of the intake manifold usually resets the ECU and if the jeep fires right up after doing this you can bet that the CPS is faulty and needs to be replaced.
-Exchange the fuel pump relay and the ASD relay with one of the other similar ones in the PDC to eliminate these relays as the cause of the no-start. Confirm that the fuel pump runs for 3-5 seconds when you turn the ignition key to ON.
-Eliminate the NSS as a cause of no start. Wiggle the shift lever at the same time you try to start. Put the transmission in Neutral and do the same. Do the reverse lights come on when the shifter is in Reverse?
-Inspect the wires and wire connectors at the O2 sensors on the exhausts pipe. A short circuit from melted insulation or from broken O2 sensor wires can blow a fuse and the ECU/ECM will lose communication.
If you buy a new CPS, get a genuine Jeep CPS, or the premium one from NAPA. Cheap crappy “Lifetime Warranty” parts are often out of specification or even failed right out of the box. They usually also have a shorter service life than better quality parts. Buy good quality repair parts and genuine Jeep sensors for best results.
Also remember to perform basic trouble shooting of the start and charge systems. Remove, clean, and firmly reconnect all the wires and cables to the battery, starter, and alternator. Look for corroded or damaged cables and replace as needed. Do the same for the grounding wires from the battery and engine to the Cherokee's frame/body. Jeeps do not tolerate low voltage or poor grounds and the ECM/ECU will behave oddly until you remedy this.
Crankshaft Position Sensor Connector (CPS/CKP)
TESTING PROCEDURE 1991 – 2001 4.0L H.O. engines
1. Near the rear of intake manifold, disconnect sensor pigtail harness connector from main wiring harness.
2. Place an ohmmeter across terminals B and C (See Image). Ohmmeter should beset to the 10K-or-2OK scale for this test.
3. The meter reading should be open (infinite resistance). Replace sensor if a low resistance is indicated.
TESTING PROCEDURE for 1987 – 1990 4.0 L engines
Test # 1 - Get a volt/ohm meter and set it to read 0 - 500 ohms. Unplug the CPS and measure across the CPS connector's A & B leads. Your meter should show a CPS resistance of between 125 - 275 ohms. If the CPS is out of that range by much, replace it.
Test # 2 - You'll need a helper for this one. Set the volt/ohm meter to read 0- 5 AC volts or the closest AC Volts scale your meter has to this range.Measure across the CPS leads for voltage generated as your helper cranks the engine. (The engine can't fire up without the CPS connected but watch for moving parts just the same!) The meter should show .5 - .8 VAC when cranking.(That's between 1/2 and 1 volt AC.) If it's below .5vac, replace it.
The 2000 and 2001 will have the CPS in the same location on the bell housing, but the wire connector is on the passenger side, near or on top of the Transfer case, not as shown in the diagram below. Simply follow the wire from the sensor to the wire connector.
Unit Bearing removal tool
Originally Posted by CCKen
Here's pics of the grounds:
G100. The main battery to chassis ground.
G101. The main ground for the PCM, TCM, and O2S heaters.
An alternate chassis to battery ground path is through the radio interence suppression bonding strap on the firewall. It's worth checking/cleaning.
Check/clean these grounds and get back with your results.
Originally Posted by un4gvn1
Ok boys & girls. Pay attention, I'm gonna lay a little homemade tool tip on y'all that makes unit bearing removal quick & easy. This will work on pretty much anything w/ unit bearings, no 12pt deep socket & power steering required (that always looks sketchy to me anyhow)
Here's the tool.
All that is required is a 1/2" x 1 1/2" bolt and a 1/2" coupling nut. One refinement that makes it a little easier to use is to embed a ball bearing in one end or the other. I haven't bothered on this one yet.
It's used like this...
Remove the lower two unit bearing bolts, loosen the upper bolt several turns. Unscrew your "screw jack" until it will stay put between the bolt & frame. Use two end wrenches (3/4" on bolt, 5/8" on nut) to unscrew the bolt in the coupling nut, jacking the unit bearing out. You will easily create a gap that will allow a pry or screwdriver to finish the job.
Actually easier to use than to explain.
I've used this on a junkyard axle when there was no steering on the axle. Takes <5min /side after calipers are off & unit bolts loose. I try to keep a couple in my trail tool box.
Originally Posted by CCKen
Here's what the inside of the HVAC Unit looks like: