No spark
Thread Starter
Joined: Jun 2006
Posts: 3
Likes: 0
No spark
Hello everyone! My dad has a 95 Dakota 4x4with a 318 in it. He has no spark! Is there a way to check the coil, pickup coil, and crank sensor? It is about 200 miles away right now, so I want to be ready to check things out when I get there. He took the coil and pickup coil out to be checked, but no parts place will check them. They will sell us new ones, but I don't want to throw money at it just to do it! Any help here would be great!
Thanks in advance!
Dan
Thanks in advance!
Dan
Champion
Joined: Dec 2003
Posts: 4,119
Likes: 5
From: Sycamore, Illinois (displaced to Arkansas)
RE: No spark
The following info is coming from the shop manual for a 1996 Dakota, but, I don't think they changed a whole lot:
Tools you will need to do the following include, but may not be limited to:
Ohmmeter
Voltmeter
Jumer wires (18 gauge or smaller, 16 gauge or smaller)
0.33 MF capacitor (RadioShack has all kinds of stuff like this), 3 alligaor clips, and some wire (if you do the little test in "failure to start" that starts on step (7)
Ignition Coil- Inspect ignition coil for arching. Test the coil according to coil tester manufacturer's instructions. Test the primary and secondary resistance. Replace any coil that does not meet specifications. Also, inspect secondary spark plug cable, replace if burned or damaged, or shows any signs of carbon tracking, as this will cause the new coil to fail.
Manufacturer | Primary Resistance | Secondary Resistance
Diamond | 0.97 - 1.18 Ohms | 11,300 - 15,300 Ohms
Toyodenso | 0.95 - 1.18 Ohms | 11,300 - 15,300 Ohms
Failure to start test:
(1) Unplug ignition coil harness connector at the coil.
(2) Connect a set of small jumper wires (18 gauge or smaller) between the diconnected harness terminals and the ignition coil terminals. (The gray wire is the ignition coil driver; the dark green/orange wire is the ASD relay output)
(3) Attach one lead of a voltmeter to the positive (12 volt) jumper wire (Which should be coming from the dark green/orange wire from the ASD relay). Attach the negative side of voltmeter to a good ground. Detirmine that sufficent battery voltage (12.4 volts) is present for the starting and ignition systems.
(4) Detirmine that sufficent battery voltage (12.4 volts) is present for the starting and ignition systems.
(5) Crank engine for 5 seconds while monitoring voltage at the coil positive terminal:
(a) if voltage remains near zero during entire cranking.. check PCM and ASD relay (located in power distribution center, to the rear of the battery, test of this is located below).
(b) if voltage is at or near battery voltage and drops to zero after 1-2 seconds of cranking, check PCM circuit.
(c) if voltage remains at battery voltage for entire 5 seconds, turn key off. Remove the three 32-way connectors from the PCM (located on the trucks left side of the engine compartment) Check the connectors for any spread terminals or corrosion.
(6) Remove test lead from the coil positive terminal. Connect an 18 gauge jumper wire between the battery positive terminal and the coil positive terminal.
(7) Make the special jumper (shown in provided picture). Using the jumper, momentairily ground the ignition coil driver circuit at the PCM connector (cavity A7, I believe a few cavities are marked on the connector, and I believe the "A" connector is the one furthest to the trucks front, there are 3)
(8) If a spark is generated, replace the PCM.
(9) If spark is not seen, use special jumper to ground the coil negative terminal directly.
(10) If spark is produced, repair wiring harness for an open condition
(11) If spark is not producted, replace ignition coil.
Crank sensor- The sensor is located on the top of the cylinder block near the rear of the right cylinder head. (3.9L / 5.2L engines)
(1) Near the rear of the intake manifold, disconnect sensor pigtail harness connector from main wiring harness.
(2) Place an ohmmeter across terminals B and C (see provided picture) Ohmmeter should be set to 1K - 10K scale for this test. The meter reading should be open (no resistance) Replace sensor if a low resistance is indicated.
ASD /Fuel Pump Relay- To Test
(1) Remove relay
(2) Using an ohmmeter, measure resistance between terminals 85 and 86. Resistance should be 75 +/- 5 ohms for resistor equipped relays.
(3) Connect ohmmeter between terminals 87A and 30. Continuity should be present.
(4) Connecto ohmmeter between 87 and 30. Continuity should NOT be present.
(5) Use jumper wires (16 gauge or smaller) Connect one jumper wire between terminal 85 (on the relay) to the ground side (-) of a 12 volt power source.
(6) Attach other jumper wire to the positive (+) side of a 12V power source. Do not connect this jumper wire to relay at this time. CAUTION: Do not allow ohmmeter to contact terminals 85 or 86 during these tests. Damage to ohmmeter may result.
(7) Attach the other jumper wire (12V +) to terminal 86. this will activate relay. Continuity should be present between terminals 87 and 30, and NOT present between 87A and 30.
(8) Disconnect jumper wires from relay and 12V source.
(9) If continuity or resistance tests did not pass, replace relay.
Test for spark at coil:
(1) Disconnect secondary cable (going from ignition coil to distributor) at the distributor end. Hold the end about 1/2 inch from a good engine ground.
(2) Crank engine with starter, to inspect for a steady arc. If steady arc does not occur, inspect the cable. Also inspect distributor cap and rotor for cracks or burn marks. Repair as needed. If steady arching occurs, reattach cable to distributor cap.
(3) Remove cable from 1 spark plug.
(4) Using insulated pliers, hold cable end appx. 1/2 inch from engine cylinder head or block, while cranking engine. Observe for an arc. If steady arching occurs, but engine will not start... the book says to connect DRB scan tool (which is Chrysler's expensive tool).
If you have any questions, want more info/troubleshooting procedures, either PM me or post back. Also, post back to tell us what the problem was.
I know, these pic's illustrations arn't the best, but, its Paint, what do you expect? lol.
ASD / Fuel Pump Relay:
[IMG]local://upfiles/948/CF7E36FE99A749C897DCC43C95E92455.gif[/IMG]
CPS:
[IMG]local://upfiles/948/250EB4A1EAB248B5991C0B769492F0BC.gif[/IMG]
Special Jumper:
[IMG]local://upfiles/948/D852232D0E634E138B605FE45E15DD96.gif[/IMG]
Tools you will need to do the following include, but may not be limited to:
Ohmmeter
Voltmeter
Jumer wires (18 gauge or smaller, 16 gauge or smaller)
0.33 MF capacitor (RadioShack has all kinds of stuff like this), 3 alligaor clips, and some wire (if you do the little test in "failure to start" that starts on step (7)
Ignition Coil- Inspect ignition coil for arching. Test the coil according to coil tester manufacturer's instructions. Test the primary and secondary resistance. Replace any coil that does not meet specifications. Also, inspect secondary spark plug cable, replace if burned or damaged, or shows any signs of carbon tracking, as this will cause the new coil to fail.
Manufacturer | Primary Resistance | Secondary Resistance
Diamond | 0.97 - 1.18 Ohms | 11,300 - 15,300 Ohms
Toyodenso | 0.95 - 1.18 Ohms | 11,300 - 15,300 Ohms
Failure to start test:
(1) Unplug ignition coil harness connector at the coil.
(2) Connect a set of small jumper wires (18 gauge or smaller) between the diconnected harness terminals and the ignition coil terminals. (The gray wire is the ignition coil driver; the dark green/orange wire is the ASD relay output)
(3) Attach one lead of a voltmeter to the positive (12 volt) jumper wire (Which should be coming from the dark green/orange wire from the ASD relay). Attach the negative side of voltmeter to a good ground. Detirmine that sufficent battery voltage (12.4 volts) is present for the starting and ignition systems.
(4) Detirmine that sufficent battery voltage (12.4 volts) is present for the starting and ignition systems.
(5) Crank engine for 5 seconds while monitoring voltage at the coil positive terminal:
(a) if voltage remains near zero during entire cranking.. check PCM and ASD relay (located in power distribution center, to the rear of the battery, test of this is located below).
(b) if voltage is at or near battery voltage and drops to zero after 1-2 seconds of cranking, check PCM circuit.
(c) if voltage remains at battery voltage for entire 5 seconds, turn key off. Remove the three 32-way connectors from the PCM (located on the trucks left side of the engine compartment) Check the connectors for any spread terminals or corrosion.
(6) Remove test lead from the coil positive terminal. Connect an 18 gauge jumper wire between the battery positive terminal and the coil positive terminal.
(7) Make the special jumper (shown in provided picture). Using the jumper, momentairily ground the ignition coil driver circuit at the PCM connector (cavity A7, I believe a few cavities are marked on the connector, and I believe the "A" connector is the one furthest to the trucks front, there are 3)
(8) If a spark is generated, replace the PCM.
(9) If spark is not seen, use special jumper to ground the coil negative terminal directly.
(10) If spark is produced, repair wiring harness for an open condition
(11) If spark is not producted, replace ignition coil.
Crank sensor- The sensor is located on the top of the cylinder block near the rear of the right cylinder head. (3.9L / 5.2L engines)
(1) Near the rear of the intake manifold, disconnect sensor pigtail harness connector from main wiring harness.
(2) Place an ohmmeter across terminals B and C (see provided picture) Ohmmeter should be set to 1K - 10K scale for this test. The meter reading should be open (no resistance) Replace sensor if a low resistance is indicated.
ASD /Fuel Pump Relay- To Test
(1) Remove relay
(2) Using an ohmmeter, measure resistance between terminals 85 and 86. Resistance should be 75 +/- 5 ohms for resistor equipped relays.
(3) Connect ohmmeter between terminals 87A and 30. Continuity should be present.
(4) Connecto ohmmeter between 87 and 30. Continuity should NOT be present.
(5) Use jumper wires (16 gauge or smaller) Connect one jumper wire between terminal 85 (on the relay) to the ground side (-) of a 12 volt power source.
(6) Attach other jumper wire to the positive (+) side of a 12V power source. Do not connect this jumper wire to relay at this time. CAUTION: Do not allow ohmmeter to contact terminals 85 or 86 during these tests. Damage to ohmmeter may result.
(7) Attach the other jumper wire (12V +) to terminal 86. this will activate relay. Continuity should be present between terminals 87 and 30, and NOT present between 87A and 30.
(8) Disconnect jumper wires from relay and 12V source.
(9) If continuity or resistance tests did not pass, replace relay.
Test for spark at coil:
(1) Disconnect secondary cable (going from ignition coil to distributor) at the distributor end. Hold the end about 1/2 inch from a good engine ground.
(2) Crank engine with starter, to inspect for a steady arc. If steady arc does not occur, inspect the cable. Also inspect distributor cap and rotor for cracks or burn marks. Repair as needed. If steady arching occurs, reattach cable to distributor cap.
(3) Remove cable from 1 spark plug.
(4) Using insulated pliers, hold cable end appx. 1/2 inch from engine cylinder head or block, while cranking engine. Observe for an arc. If steady arching occurs, but engine will not start... the book says to connect DRB scan tool (which is Chrysler's expensive tool).
If you have any questions, want more info/troubleshooting procedures, either PM me or post back. Also, post back to tell us what the problem was.
I know, these pic's illustrations arn't the best, but, its Paint, what do you expect? lol.
ASD / Fuel Pump Relay:
[IMG]local://upfiles/948/CF7E36FE99A749C897DCC43C95E92455.gif[/IMG]
CPS:
[IMG]local://upfiles/948/250EB4A1EAB248B5991C0B769492F0BC.gif[/IMG]
Special Jumper:
[IMG]local://upfiles/948/D852232D0E634E138B605FE45E15DD96.gif[/IMG]
Thread Starter
Joined: Jun 2006
Posts: 3
Likes: 0
RE: No spark
WOW, I didn't think it would be so involved! Thank you for taking the time to do that!!! I have it all printed out, and will gather the things I need for the weekend trip! I'm going up there Friday, staying for the weekend, then going on to Arkansas! If I don't get back to a computer before the 4th of July, don't be surprised! Thanks again for the info, he wanted to junk it, I can't let him do that. This is the first thing that has happened to it.
Dan
Dan
Thread Starter
Joined: Jun 2006
Posts: 3
Likes: 0
RE: No spark
It seems that the wires were eaten by mice! It sure was an easy fix. That gave me plenty of time to do some fishing with him, got to spend lots of time together having fun instead of working on the truck! He hadn't used his boat this year, so I talked him into it! Thanks for sending the info, I'm glad I ended up not needing it! Now I have to talk him into bigger tires!
Dan
Dan
