Top 10 1998 Jeep Wrangler Questions & Answers

Try this disconnect the heater hoses from the heater core use a hose to backflush the core. Then reconnect and try again.

Your transmission should still work if the solenoid goes bad. It will just shift funny

I would check your headlight relay switch that is located in your steering colum

oil pump going, or the crank bearings worn.
are there any noises that appear when oil pressure drops?

check sensor

Check out the diagram:


The removal of the thermostat from its housing on the 4.0L engine

To install:

1. Install the replacement thermostat so that the pellet, which is encircled by a coil spring, faces the engine. All thermostats are marked on the outer flange to indicate the proper installed position.
   
2. Observe the recess groove in the engine cylinder head .
   
3. Position thermostat into this groove with arrow and air bleed hole on outer flange pointing up.
   
4. Install replacement gasket and thermostat housing
   
   CAUTION Tightening the thermostat housing unevenly or with the thermostat out of its recess may result in a cracked housing.
   
   
5. Tighten the housing bolts to 15 ft. lbs. (20 Nm) torque.
   
6. Install hoses to thermostat housing.
   
7. Install electrical connector to coolant temperature sensor.
   
8. Be sure that the radiator draincock is tightly closed. Fill the cooling system.
   
9. Start and warm the engine. Check for leaks
   

WARNING Do not loosen radiator drain **** with system hot and pressurized. Serious burns from coolant can occur.



NOTE Do not waste reusable coolant. If solution is clean, drain coolant into a clean container for reuse. If thermostat is being replaced, be sure that replacement is specified thermostat for vehicle model and engine type.

Are you sure that this is for 20AMP, according with the repair manual, the position 20 in the Power Distribution Center if for Power Motor ABS Pump, and is 10AMP.

Verify it..

Click of the following direct, Free Link. It has several Serpentine Diagrams, including the one for your 1998 Jeep Wrangler 4.0L In-Line 6-Cylinders based upon your Engine Options (AC/No AC, Power Steering/No Power Steering, etc.).
The Link Page ALSO has the 2.5L In-Line 4-Cylinder Serpentine Belt Diagrams with their various engine options.
Included are the with AC / without AC Routing.

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.com!
http://www.2carpros.com/car_repair_information/year/1998/make/jeep/model/wrangler/1998_jeep_wrangler_drive_belt_routing_diagram.htm

a quick fix is to look under the hood, look for where the intake meets the throttle body, you will see a bolt which can be adjusted. When you start to screw it out, your idle will decrease...

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.

engine pan or trans pan,(guess at engine)
what's up doc.?
what is the job.
lost the gasket?
lost the bolts.?
not sure what going on here.
buy a new gasket from Felpro and bingo? there be a pattern