1998 Jeep Wrangler - Page 6 - Answered Questions & Fixed issues

So it gets spark and fuel correct? Have you checked the compression?

Sounds like a blown fuse. Check all the fuses in the fuse panel. Replace the one thats bad.

bad fuel pump can cause this or plugged fuel filter but i believe they are one unit

Its the horn button and/or a broken wire completing the circuit, and bypassing the switch. You will find both under the center cover in the steering wheel. If an air bag is also there, disconnect the battery and wait 10 minutes BEFORE removing the cover. Also, do not disconnect the battery with out first installing a "memory keeper" low voltage power source in the cigarette lighter socket.
If you don't the radio and the whole car will lock you out and do nothing. Thank the theft system for that!!

It could also be the relay for the horns. Usually in one of the under hood power distribution boxes. Swap the relay for another identical relay and see if the horn stops blowing by itself.

this is for a system with a/c. If you don't have a/c let me know and I will get you the correct one but i'm sure that you have a/c and power steering.

To diagnose Diagnostic Test Code (DTC) P0123, you will need a scan tool that can read computer data and a digital Volt/Ohm meter.

Check the sensor data in the computer and see if it is showing TPS voltage higher than 4.5 volts. If it does not, then you may have a computer that is malfunctioning internally.

If it is reading the TPS voltage higher than4.5 volts, then you need to back-probe the TPS signal return circuit and verify the actual voltage with the digital Volt/Ohm meter with the ignition in the ON position.. If the voltage is higher than 4.5 volts and the meter reading agrees with the computer data, then this is not an internal computer error - (the computer is telling you the truth)

Then you should check the 5 volt reference voltage at the sensor connector with the connector disconnected from the sensor with the ignition in the ON position. If the reference voltage is higher than 5.3 volts, then the reference circuit is shorted to power. (possibly shorted to another wire that is SUPPOSED to have higher voltage)

If the reference voltage is correct, check the sensor ground. With the sensor connected and the ignition in the ON position, back-probe the sensor ground wire at the TPS connector and connect the POSITIVE lead of the Volt/Ohm meter to the back probing pin and the NEGATIVE lead to battery ground. Put the meter on a one volt scale if it is equipped with one. Otherwise, put it on the lowest scale possible. You should have a reading of 200 MilliVolts or less (preferably ZERO). If the voltage reading here is more than 200 millivolts, your problem is being caused by a bad ground circuit.

If all of the above checks out OK, replace the TPS.

See wiring diagram for a better understanding of what we are trying to do here.

try pulling one fuse out at a time,then blow the horn & if it still works replace that fuse & pull another one out until you discover which is the right one,but only remove one at a time....hope this helps.....cheers.

Hopefully there is fuel in the tank. Also listen to see if you can hear the pump kick on when you turn the key on. If you have fuel in the tank and you can hear the pump running put a fuel pressure guage on it to see if you are getting pressure. If you are getting pressure check to make sure the injectors are working.

BAD CRANK SENSOR ON TOP OF ****** HARD TO SEE FOLLOW WIRES, OR FUEL PRESSURE LOW BAD PUMP IN TANK..RENT TOOL AT AUTO ZONE HOOK UP TO FUEL RAIL SHOULD HAVE AT LEAST 45 50 PSI OF PRESSURE IF GOOD THEN CRANK SENSOR.WHEN IT DOESNT START CHECK FOR SPARK IF NO SPARK GOOD CHANCE ITS BAD.ITS ABOUT 45.00 BUCKS FOR NEW ONE AND ABOUT 35MIN TO PUT ON.GOOD LUCK

Very first thing you need to do is verify the actual oil pressure using a mechanical gauge. Lowest pressure at idle, with a warmed up engine would be 20psi. I'd rather see it at 30.
If the pressure is good, then you could have a valve lifter or rocker arm that has worn. Those cause tapping noise, not knocking. Knocking is usually caused by a worn rod or main engine bearing. When either wear, oil pressure gets lower (why I said to check that) Knocking can also be caused by an undersized piston or a cracked flywheel (common on automatics). Piston noise generally only happens cold and is much less common than it use to be in Jeep engines.
So, everyone that gave you info on your problem may be right...The only way to know for sure would be to have someone that is experienced and honest check it out for you. How expensive the repair is will entirely depend upon what the actual diagnosis is.

Thanks for choosing FixYa and welcome to the site. What guages are going out? Do they go out at the same time?

Give me some more information about this problem. May be i can help.

• On the left side of the transmission there is a slave cylinder.
• You want to remove them two bolts.
• Take that roll pin out. It's by where the line enters.
• Attach a line to the slave cylinder and stick that pin back in it's hole.
• Now take the cap off the master cylinder and make sure the liner is not left behind. You need the fluid to be able to flow.
• Fill the master half way or so.
• Now you want to hand pump that slave cylinder by hand until there are no more bubbles appearing in the master.
• Keep an eye on the fluid level in the master while doing this to make sure the master don't dry up.
• When all bubbles are gone everything should be nice and bled.
• Remove the hose from the slave cylinder and put things back as the were.
• Double check the fluid level.
• Replace the master cap.
• Your clutch is now working.

• Hope this helps and thank you for using FixYa.

Regards, Tony

FIRST NEED TO RELIEF FUEL PRESSURE REMOVE GAS CAP RELIEF GAS PRESSURE IN FUEL TANK.THEN REMOVE FUEL PUMP RELAY THEN START ENGINE UNTIL IT DIES LACK OF FUEL,CRANK ENGINE OVER FEW MORE TIMES MAKE SURE FUEL OUT OF FUEL LINES. THEN YOU NEED TO REMOVE AIR CLEANER CROSS OVER TUBE ABOVE FUEL RAILS. DISCONNECT LINES AT THE ENDS OF THE FUELS RAILS ASSEMBLY. MARK AND DISCONNECT THE FUEL INJECTOR WIRE HARNESS CONNECTORS. REMOVE THE FUEL RAIL RETAINING BOLTS, DISCONNECT THE VACUUM LINE FROM THE FUEL PRESSURE REGULATOR. REMOVE THE FUEL RAIL ASSEMBLY FROM THE ENGINE. IF YOU HAVE AUTOMATIC TRANSMISSION REMOVE THE THROTTLE PRESSURE CABLE AND BRACKET TO REMOVE THE FUEL RAIL ASSEMBLY.TO REMOVE FUEL INJECTORS JUST REMOVE CLIPS THAT RETAIN FUEL INJECTORS IN FUEL RAIL. BESURE GO TO DEALERSHIP BUY NEW FUEL INJECTORS O - RINGS.APPLY A SMALL AMOUNT OF ENGINE OIL TO THE O - RINGS TO AID IN INSTALLATION. TORQUE FUEL RAIL BOLTS TO 100 INCH LBS.

Top drivers side of transm.bell housing

This is basic, but first off, try to shift it into neutral, and try to start it. It is easy for the linkage to get out of adjustment, where it thinks the jeep is in gear. If that does not work, make sure you have battery power to the ignition and starter.

Somewhere in the world there may be a specification for that but in reality, just make the pulley through bolt tight (without being and animal on it). The long jack bolt gets tightened first. There, you check belt deflection. You should have about one inch or slightly less deflection in the center of the longest run of the belt. After getting it to that point, lock it and tighten the pulley. Run it for a few minutes and then drive it. If the belt squeals, loosen the adjustment and give it a few more turns. Do not over-tighten it. A loose belt will be noisy. An overtightened one can destroy component bearings.

Remove, clean, and reinstall the cable connectors at the battery. Even if they LOOK clean, that may not be the case. Also, check the connections from the battery to the starter. Any of these connections being bad will cause a no power condition. There is also a power distribution center under the hood. It is a rectangular black box by the battery. There is a relay and maxi fuses for the engine power that comes straight from the battery. Check those maxi fuses.

Sounds like a fuel problem; the fuel rail should be over 30 psi so you should get a good spray if you purge the release valve. Does the fuel pump kick on when you turn it over? I would have the fuel system pressure tested if it does, if not you got some electrical problem. Also I would look at coil, CKP (Crankshaft Position) sensor.

Additionally, check if when your try to start the gauges works (fuel gauge and voltimeter); if not, then the engine controller (PCM or Powertrain Control Module) is down. It could be the controller itself or an outside electrical problem that is taking it down. A lost power or ground feed to the module, a sensor ground circuit shorted to voltage or a reference voltage circuit shorted to ground will all cause the engine controller to go down.

You will have no spark, no fuel pressure, the fuel gauge and voltmeter on the dash won't come up with the key on. There won't be any communication with a scan tool because the PCM is dead to the world. A common cause for this is an internally shorted crank position sensor. This is mounted at about the 11:00 position on the bellhousing as viewed from behind, and the electrical connector comes up to the back of the intake.

Start by unplugging the crank sensor and see if the fuel gauge and voltmeter come up. If they do, replace the crank sensor with a Mopar part. If unplugging it doesn't make the gauges come alive you'll need to do some deeper electrical testing to see why the controller is down. I would start with the powers and grounds, then move on to the reference voltage and sensor ground circuits. I can help you with that if you've got a voltmeter and want to get into some testing while it's acting up.

Hope helps; keep us updated.

No,you should be able to get to it with a sparkplug swivel socket, its a little tight but you can get to it,good day,