Low to no spark to plugs,I have a 99 dodge ram 1500,318,2wd.I replaced the dist cap,rotor,wires.I have strong spark from the coil to the cap but barley or no spark at the plugs.Rechecked plug wires,cap and rotor and all is fine but still not getting any fire.I checked all relays and fuse and still no fire.Anyone have a clue as what could be causing this?

Do you mean you can take off the coil to dist. high tension cable at the distributor end, and you get spark from the coil? If the spark is strong and blue, then the only thing between that and the spark plug wire end is the distributor cap and rotor. Both are high wear items, good to replace them every hundred thousand or two. Miles, that is.

An ignition system has a primary and a secondary circuit. The secondary circuit is the high voltage coming out of the coil to the top of the distributor, where it touches the top of the rotor, and the current is passed from the center of the rotor to the tip, where it whisks by the metal tip on the dist. cap where a spark plug wire connects. So a continuous current from the coil to the individual spark plug wires, and to the plugs. It's only an instant, but it's a current flow from origination in the coil to ground. When the current reaches the bottom of the spark plug, it has to jump a gap to find a ground. When it jumps, it conveniently makes a spark.

If the cap got cracked when installed, it could cause this to happen, even with a brand new cap. The split can be a hairline and almost impossible to see, but will cause arc-tracking and shorting out.
To test if this is a possibility, spray a light coating of WD-40 on the top of the cap. The silicone oil is a great insulator and will temporarily fill the split and keep the spark from shorting out.

could be your coil, but can also be internal, have you replaced both the air & fuel filters ? if so, dump some good fuel injector cleaner into tank when half empty , top off with 91-92 octane fuel, see how that works for you, do some highway driving, stop & go traffic creates problems, todays fuel w/ethonal is bad for older cars, be sure to have code cleared from ecm !

Check the plugs to the computer on the passenger side of the firewall. there are three of them, unplug them, wait ten or eleven minutes and plug them back in. if that does not work you might have a computer problem or a bad ground wire at the battery
By the way my 99 has the original plugs, wires, rotor, dist cap, and coil, from the factory. I have driven it every day for 11 yrs. over 12,000 foot mountain passes, four wheeling trips every weekend, and dozens of trips across the country. I have over 260,000 miles on it. I think you get the point...
By the way diesel boys this is a gas engine simply well maintained!!!!!!!!!!!!!!!

Hi, Hope I can help you.
I do not know how you have checked for spark, but lets start from the beginning.
Lets start with an ignition systems check.
1. I want you to remove the high voltage coil wire. ( That's the wire in the center of the distributor cap.) Using a good pair of insulated pliers. I want you to hold it about 1/4 inch from a good engine ground. Now you will need a bit of help from a partner. Get them to turn the key and crank the engine. You should see a bright blue and well defined spark. Ok, If you have spark I want you to slowly move the coil wire away from the engine ground. As you do this I want you to pay attention to the coil tower. (The coil tower is where the other end of the coil wire is attached.) What your looking for is arcing and sparking at the coil tower. If this happens then you need to replace the coil with a new one. If this does not happen then your coil is working fine, and we will have to move on.
Note if you do not get spark from the coil wire replace the coil.

2. Ok if you have spark now we have find out if the spark is making it to the spark plugs. How are we going to do this? By checking the rotor, distributor cap, spark plug wires and spark plugs.First lets remove the distributor cap. This will allow use to inspected the rotor and the distributor cap. What your looking for is, cracks, carbon tracks and wear at the tip of the rotor. On the distributor ,look inside the cap for cracks, carbon tracks and wear on the terminals. If you find any of this replace the distributor cap and rotor. ( Note if you have any doubt of the condition of the rotor or the cap replace them.) Next lets check your spark plug wires. Lets pull off one of the spark plug wires from the spark plug side. Now inspect the wire connection for a white crusty powder. If you find crust replace your wires. Now you should check all of them the same way, but if even one has corrosion replace them all. You are going to have to inspect the wire its self . Going down the whole length of the wire. Holes cracks burn Marks and other damage. Once again if you find any damage replace them all.
I hope this will help you and good luck to all the read this FixYa

then i would replace whats called the hall effect sensor its that black plastic plate you see when you take dist cap off. just pull rotor and lift up the sensor.dist cap is what holds it on.also under the sensor will be a stamped sheet metal piece that looks like the top of a castle wall. make sure its not loose on the shaft.if it is then new dist will be needed

it could be the rotor arm or dissy cap worn i had the same fault with my rangerover v8 i changed them and it was fine

do you have spark coming from your coil to distributor,or no spark right from coil? if you have spark coming from coil, and nothing at any plugs,check you dist. cap and rotor button.Chrysler's are famous for the cap and rotor button to corrode,you may be able to just clean the corrosion off with some fine sand paper,or might have to replace them. if you have no spark coming from coil,check for power and ground to coil.if both are present, replace coil.

Hi
Here is a diagram.

check the wiring harness at the coil,sometimes that plug will get loose or dirty resulting in a no spark.
The only ign system parts are the crank sensor,cam sensor,dist,dist cap,rotor,spark plugs,wires,and coil,and the ecm which controls all of these,is there a check engine light on?
run a scan tool to check for stored codes or system events stored in the ecm.