1. Ignition Switch:
* Check the ignition switch itself: It's possible the switch failed internally, cutting power to the ignition system. This is a common point of failure. You can test this with a multimeter to see if power is getting to the coil's positive terminal in the "start" position. If not, the ignition switch is a likely suspect.
2. Ignition Control Module (ICM): (Often near the distributor on older vehicles)
* Visual Inspection: Look for any obvious damage, loose connections, or burned components.
* Testing (Advanced): This requires a multimeter and a bit more electrical knowledge. You need to check for power and ground at the ICM's connections, as well as checking its output signal. A faulty ICM is a common cause of sudden ignition failure. Consult a wiring diagram specific to your 1988 Dodge Dakota to identify the ICM and its connections.
3. Crankshaft Position Sensor (CKP): (Important for spark timing)
* Location: The CKP sensor's location varies by engine. Check your repair manual or online resources. It usually sends a signal to the ICM to tell it when to fire the spark. A failing CKP sensor won't let the ICM know when to trigger spark.
* Testing (Advanced): You'll need a multimeter to check the sensor's output signal. This requires testing the signal wave form.
4. Distributor (Less Likely):
* Rotor and Cap: While less likely to cause a sudden failure *while* driving, a cracked rotor or severely corroded distributor cap could cause intermittent or complete spark loss. Inspect them carefully for any damage.
* Pick-up coil: A faulty pick-up coil within the distributor could also prevent the sending of the signal to the ICM.
5. Wiring:
* Harness Inspection: Check the wiring harness connecting the coil, distributor, ignition switch, and ICM for any broken wires, loose connections, or corrosion. Pay close attention to areas that might have been subjected to vibration or heat. A rodent chewing through wires is not uncommon.
Troubleshooting Steps:
1. Start with the easy stuff: Check all fuses and relays related to ignition.
2. Visual Inspection: Thoroughly examine all components mentioned above for physical damage.
3. Multimeter Testing: If you're comfortable with basic electrical testing, use a multimeter to check for power and ground at the coil, ICM, and other ignition components. (Refer to your vehicle's wiring diagram)
4. Professional Help: If you're not comfortable with electrical diagnostics, take it to a qualified mechanic. Incorrect testing could damage components.
Important Notes:
* Repair Manual: A factory service manual for your 1988 Dodge Dakota is invaluable for this kind of troubleshooting. It will have wiring diagrams and testing procedures.
* Safety First: Always disconnect the negative battery cable before working on any electrical components.
The sudden failure while driving points towards a component that failed completely rather than a gradual wear-out. The ICM and CKP sensor are strong suspects given the symptoms. Begin with the simpler checks (fuses, visual inspection) before moving to multimeter testing. If you're uncertain about electrical testing, it's best to consult a professional.
