2.3L engine pics

Often in the repair manuals their pictures would either suck or just never seem to show the one part, wiring, or location I needed to see.  So here is a few that might help you.

Cleaned intake

Old ignition module

Crank sensor

 Test plug sprout

Lower coil mount

Spring detail

Ignition Control Module R&R - 1991 Ranger

Tips you can use. This control module job can go great or poorly. Mine went poorly.

Outside of the fact that the unit is buried behind the alternator and not wrench friendly, my bolt heads were rusted beyond use.  This would require the removal of the lower intake in order to to attempt the removal of the unit.  Ultimately one bolt would snap, The other two bolts came out heat and oil, but only after breaking the unit off the bolts, so I could use vise grips on the bolts.

TIP1: Heat is the enemy of the ignition control module.
Note there are only three bolts.  The lower two are also grounds (verify the vehicle ground to manifold located at #4 cyl on manifold is good).  Clean the backing plate well before installing a new unit.  Note which plug is UP. Use anti seize compound on the bolts. Use heat compound or di-electric grease under the module required for heat transfer.

TIP2: Use a tap to clean the threads before installing bolts.  If they break off during removal, you may need to remove the manifold.

TIP3: Remove the sensor from the manifold located in the tube to #1 cylinder. This is often choked with crap from the EGR system. Clean with a blast of carb cleaner and reuse.

2.3L fuel injector removal and service

These are a type EV-1 style. Go HERE.

Coil Pack Pins

Identify the connector pins on the ignition coil assembly. If you look at the electrical connector you unplugged on the ignition coil assembly, you will see three small pins inside. The one in the center is B+. 

Fig. Fig. 2: Engine ignition coil harness connections-2.3L, 2.5L and 5.0L engines

Disconnect the spark plug wires from the ignition coils on the assembly by hand. The wires have a locking tab. To disconnect them squeeze the locking tabs inward at the terminal and twist the boot while pulling up. This also a good time to check the resistance of the spark plug wires and check for damage as you have them apart already.

Removing the coil pack and bench testing is best.  Often there is cracking and damage on the underside of the unit which only can be seen if it is removed and cleaned.

Get a multimeter (digital is best) and set it to the correct range for ohm testing.

Checking the ignition coils' primary resistance. Probe pins B+ and coil 1 of the connector on the ignition coil assembly, and make a note of the number on the multimeter readout. Then probe pins B+ and coil 2.  Make a note of each of your meter readouts. The resistance value for each pair of pins in your three tests should be between 0.3 and 1.0 ohms. If any of the coil packs (2 per unit) test out of this range (over or under), the pack should be replaced.

Check the ignition coils secondary resistance. Select the appropriate range in your multimeter so you can read between 6,500 and 11,500 ohms in the ohmmeter scale. Probe the two terminals on coil 1, where the spark plug wires 1 and 4 connect to, and make a note of your multimeter readout number. Probe the terminals on coil 2 and 3 and make a note of the results, as well. Any coil that tests outside of the 6,500 through 11,500 ohms range should be replaced. On 2.3L, 2.5L and 5.0L engines, if one coil pack is found to be defective, the other pack does not need to be replaced.

If any pack tested bad in either test, replace the unit.

The condenser usually mounted to the coil pack goes bad often creating a ignition miss, replace this item.

If the pack is good, reconnect the electrical plug, spark plug wires and the negative battery cable. 

Other sensors that effect the timing are: MAP ( Manifold Absolute Pressure sensor ), IAT ( Intake Air Temperature sensor ), ECT ( Engine Coolant Temperature sensor ), EVP ( EGR Valve Position sensor ) and TPS ( Throttle Position Sensor ).

Air Bypass Valve Info and testing

Ford air bypass valve

The ford ranger air bypass valve solenoid is used to control engine idle speed and is operated by the EEC-IV control module. This valve allows air to pass around the throttle plates to control:

1. cold engine fast idle
2. no touch start
3. dashpot
4. over temperature idle boost
5. engine idle load correction.

Symptoms of a bad one:

1. Engine stalling
2. Surging
3. Poor idle conditions
4. "Check engine light" on

Diagnosis:

The signal to the solenoid should be 1 volt or less at curb idle, (with all accessory loads off). Applying 12 volts to the solenoid will cause a neutral idle speed change greater than 1000 rpm. Check for shorts between both solenoid terminals and the case.

Codes 12, 13, 16, 17 & 19 all indicate idle speed is out of spec (too high or too low). Codes 47 and 48 indicate a fuel mixture problem which could be caused by an air leak. It may be possible to clean the ports with electrical safe clearer, do not use regular carb cleaner as it will remove the protective coating. Clean port holes in the manifold also before reinstalling.

Ranger brake proportional valve

This proportional valve is next to the transmission mounted to the frame, drivers side, toward rear of engine. It will most likely take some heat to get the old line fittings out. You can get a new valve at Rock Auto online.  About $120. Use never seize on the line fittings when you replace it.

Update: Ranger power loss, bogging, no acceleration

The catalytic converter was not the only problem. I decided before spending the money for a new cat, I would beat out the inside of the old one first.  A tougher job than you might think.  Took about hour or so and I need a heavy wire hook to remove metal packing and a pipe to break the inside up and a vacuum to suck the inside out also.

Fuel rail schrader valve

On the initial test drive, the problem returned and I wound up on the side of a busy highway.  Once again finding no problem, I started back to the basics.  I checked the fuel rail (for gas) using the schrader valve on the rail. The picture is not my truck, but this is what it looks like on the truck. Much to surprise it was full of air and not fuel.

I have not checked this out fully yet. More later.

Update:
Yes, low on gas was this problem.  However, the power loss problem was still not solved. The short answer turned out to be a combination of several problems.

Clogged sensor

1. The air sensor in the intake manifold was coated with goo.  Cleaned and reinstalled.
2. The ignition module was bad.  See detail elsewhere on site.
3. The inner air passage inside the intake to the EGR valve was blocked/choked. So bad it had no flow. Use a McDonalds straw to probe it on your truck. The straw (5/16) is just the right size, the tunnel is straight.
4. The ground wire on the intake (needed for the ignition module) was weak. Replaced it.
5. The intake was very very dirty. Cleaned it.
6. Decided to replace the injectors with a set from a mustang 4 cly 2.3L. Mine were rusty and needed a cleaning. By the way, they work great.
7. The blocked cat converter was "cleared" earlier.

Look at odd shape near center - Egr clogged vent