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**Superman** · 4-10-04, 23:33

Raising / dropping rpm in gear

Clutch-If the clutch is slipping while engaged the engine load will decrease, causing the engine rpm’s to increase. If the clutch slips while disengaged the car will be placed in gear, forcing the car rpms to raise to the gear. This can only be solved by replacing the clutch.
Flywheel-This is not a consistent problem. If the flywheel becomes over heating the engine will be unable to maintain it’s rpm’s.
Distributor or Ignition-By far the most common failure, this is slightly harder to check for failure. To check the distributor you must remove it, using an ohmmeter touch the probes to the primary terminals of the coil, measure the primary resistance and it should measure up as follows:

93 and 94 models .6 to .11 ohms

95 and up models .4 to .73 ohms

Then touch the probes to the secondary terminal and the positive terminal, measure the resistance and it should measure as follows:

93 and 94 models 11.5 to 18.5 K-ohms

95 and up models 20 to 31 K-ohms

Both of these readings are designed for 70 degrees coils, so some variance will come into play based on coil temperature. If the coil fails this check, replace it.

Spark Plugs-The spark plugs could be worn out, therefore causing the engine to miss fires and perform poorly. Visually inspect and replace if necessary.
Spark Plug Wires-The spark plug wires can also wear out, though uncommonly tested they should read around 5000 ohms of resistance per foot (oem).
Crankshaft sensor(s)-This determines the timing for the fuel and ignition on each cylinder as well as the engine rpm. Failure should throw an engine code, but not always. Depending on the years, there are either on or two sensors.

To check the distributor mounted sensor remove the distributor, but place the larger of the two connectors, and using a voltmeter probe the sensor terminal (if I remember correctly it’s inside the distributor housing or cap). Then rotate the distributor shaft by hand one full turn and note the voltmeter reading. For a 4 cylinder, four volt pulses should occur and 6 pulses on the 6 cylinder. If this is not true, replace the sensor.

This only applies to the 96 and 96 (OBDII) models I believe. To check the motor mounted sensor (located to the left of the air conditioner pulley) measure the gap between the sensor and its trigger wheel on the crankshaft. It should be between .02 to .059 inches thick. The gap is not adjustable; if this does not match replace the sensor (if the vehicle has a detachable bracket, replace this instead). Next, disconnect the electrical connecter at the sensor and probe terminals A and B (first two on the left) with an ohmmeter. Resistance should be between 520 and 580 ohms. If the reading is incorrect, replace the sensor.

Engine coolant-Being low in engine coolant can cause this as well, or at least it comes up many times in threads.

4-10-04, 23:33	#26 (permalink)
Superman Join Date: Dec 2002 Location: Jacksonville, FL, USA Age: 23 iTrader: (0)	Raising / dropping rpm in gear Clutch-If the clutch is slipping while engaged the engine load will decrease, causing the engine rpm’s to increase. If the clutch slips while disengaged the car will be placed in gear, forcing the car rpms to raise to the gear. This can only be solved by replacing the clutch. Flywheel-This is not a consistent problem. If the flywheel becomes over heating the engine will be unable to maintain it’s rpm’s. Distributor or Ignition-By far the most common failure, this is slightly harder to check for failure. To check the distributor you must remove it, using an ohmmeter touch the probes to the primary terminals of the coil, measure the primary resistance and it should measure up as follows: 93 and 94 models .6 to .11 ohms 95 and up models .4 to .73 ohms Then touch the probes to the secondary terminal and the positive terminal, measure the resistance and it should measure as follows: 93 and 94 models 11.5 to 18.5 K-ohms 95 and up models 20 to 31 K-ohms Both of these readings are designed for 70 degrees coils, so some variance will come into play based on coil temperature. If the coil fails this check, replace it. Spark Plugs-The spark plugs could be worn out, therefore causing the engine to miss fires and perform poorly. Visually inspect and replace if necessary. Spark Plug Wires-The spark plug wires can also wear out, though uncommonly tested they should read around 5000 ohms of resistance per foot (oem). Crankshaft sensor(s)-This determines the timing for the fuel and ignition on each cylinder as well as the engine rpm. Failure should throw an engine code, but not always. Depending on the years, there are either on or two sensors. To check the distributor mounted sensor remove the distributor, but place the larger of the two connectors, and using a voltmeter probe the sensor terminal (if I remember correctly it’s inside the distributor housing or cap). Then rotate the distributor shaft by hand one full turn and note the voltmeter reading. For a 4 cylinder, four volt pulses should occur and 6 pulses on the 6 cylinder. If this is not true, replace the sensor. This only applies to the 96 and 96 (OBDII) models I believe. To check the motor mounted sensor (located to the left of the air conditioner pulley) measure the gap between the sensor and its trigger wheel on the crankshaft. It should be between .02 to .059 inches thick. The gap is not adjustable; if this does not match replace the sensor (if the vehicle has a detachable bracket, replace this instead). Next, disconnect the electrical connecter at the sensor and probe terminals A and B (first two on the left) with an ohmmeter. Resistance should be between 520 and 580 ohms. If the reading is incorrect, replace the sensor. Engine coolant-Being low in engine coolant can cause this as well, or at least it comes up many times in threads.
	Formerly xxtavixx