Ignition wires worn out?

You ohmed them but did you check them for continuity to GROUND, to find out if one of them is grounded out ! They normally ground to ecm/pcm not to eng. so check them for short to grd with wire harness unplugged from all injectors and check 1 at a time, If they all show open...no ground then check your power should be pink for chafing or bare short to ground. this will be on Bank 2 you are checking which is the Head that setsfarthest back to firewall. Bank 1 is Head farthest to front towards Radiator.

did you change the lead wires? The wires could be the problem.

the ignition cylinders on these cars get worn out over the years and the antitheft module, which is designed to measure resistance values in the cylinder when the key is turned gets readings that are out of spec, resulting in a false resistance reading. There are two solutions: replace the ignition cylinder, which is somewhat expensive, or drop down the glovebox to access the theft module and put a 2000 ohm resistor in line with a wire that goes to the modules' input feed. The resistor costs 15 cents at Radio Shack and it is not that hard to do-it disables the factory alarm, but you will not have that issue again. I have done this fox on a number of late 90's-early 2000's cars, and it always works.

Most of this came from TSB 98-T-49A, and a few of my tips thrown in.

Both P0340 and P0341 both relate to the Camshaft Position Sensor(I will just call it Cam sensor from now on), the only problem is that the S-Series engines don't have a Cam sensor, not a typical one at least. instead, the DIS module watches when the #4 spark plug fires on the compression cycle and fakes a Cam sensor signal from it. the tricky part is that on a DIS waste spark system, spark plugs fire with their mated cylinders(1/4 and 2/3 in 4 cylinder engines) every time the cylinder is at TDC, regardless of weather the cylinder is on exhaust or compression. However, it takes far more voltage to fire a spark plug on the compression stroke then on the exhaust stroke, due to the compressed air(more air molacules, more air the spark needs to jump, more resistance to spark). The increased voltage needed on the compression stroke is detected by the "#4 sensing circuit" inside the DIS module for the Cam sensor signal. if the resistance of the secondary system is not in the proper range or something else is affecting the voltage draw, the "#4 sensing circuit" will be unable to work properly.

In short, anything worng with the ignition system, bad Cam sensor signal.

Next for the diagnositic, i'm converting this from a graphic map to a text format, so bear with me...

Step 1: remove secondary wires from spark plugs, keep the wires on the coil. measure resistance from #1 wire to #4 wire and then #2 wire to #3 wire. resistance should be 11k ohms to 45k ohms(YIKES thats a wide range)

If resistance is in specs, go to step 2, if not in specs, go to step 3


Step 2: remove secondary wires from the coil packs. check for corrosion on the towers and wires.

If there is corrosion, go to step 4

If not, go to step 5


Step 3: remove secondary wires from the coil packs. check for corrosion on the towers and wires.

If there is corrosion, go to step 4

If not, go to step 6


Step 4: Replace or clean coils and/or wires as nessaciry. Retest to confirm.


Step 5: Remove spark plugs. Check for carbon or abnormal wear and proper gap(0.040 in)

If plugs check out good, go to step 8.

if the plugs are bad, replace as needed and retest to confirm.


Step 6: Measure resistance of individual secondary wires. specs are 1.5k ohms to 15k ohms ( thats what this chart says, but my knowage says 8k ohms is normal, greater then 12k ohms should be replaced)

If wires are in spec, go to step 7

If wires are bad, replace as needed and retest to confirm


Step 7: Measure resistance from tower to tower on the coil packs (hold tight for good reading). Spec is 8K to 15K.

If coils are in spec, go back up to step 5

If coils are bad, replace as needed and retest to confirm


Step 8:(90% of the time i bet the problem is solved by now) Start engine. Perform underhood visual inspection of the ignition system, check for arcing(best done in a dark area, if you are inside a garage, besure the exhaust is vented). Wet DIS module, coils, and secondary wires with salt water to provide optional ground path.(arcing from the wire boot to the valve cover is possible, but would be hidden)

If arcing is present, replace wires or coils as needed and retest to confirm.

If not, go to step 9.


Step 9: Turn ignition off, backprobe J3D03 (Circuit 633, brn/wht wire) at PCM with voltmeter. connect other lead to ground. Turn ignition on, engine off. Measure voltage.

less then 4.5 volts, go to step 10
4.5-5.5 volts, go to step 12
more then 5.5 volts, go to step 11


Step 10. Check connections in circult 633, repair short to ground, retest to confirm


Step 11. Repair short to voltage in circuit 633, retest to confirm.


Step 12. Start engine, at idle observe voltmeter

less then 2.0 volts, replace DIS module, retest to confirm
2.0 - 4.0 volts, problem intermittent
4.0 - 5.5 volts, go to step 13
more then 5.5 volts, go back up to step 11


Step 13. Turn ignition off, backprobe circuit 633 at DIS module with voltmeter, other lead to ground. check voltage.

4.0 volts or less, repair open/high resistance in circuit 633, retest to confirm.
greater then 4.0 volts, go to step 14


Step 14: Inspect terminal on DIS module for looseness or poor connection.

If terminal is bad, repair it
If terminal is good, replace the DIS module.



thats all of the diagnoistic chart, anybody who has done this in the past feel free to throw in your tips/opinons. I would like to add three things:

1. Check the grounding bolt on the DIS module for corrosion.
2. besure the secondary wires are fully seated, you should feel/hear a click
3. use dielectric grease on the coil towers

If you are not getting spark to any of the cylinders, then check your distributor cap for cracks, even very tiny ones. If you have ignition coils, then check the specs with an OHM meter. The OHM meter can also be used to check the plug wires.

Hmm, do you have spark? fuel pressure must be between 30 - 40 psi test the ignition coils by connecting an ohmmeter between the coil towers ie 1and 4 with the key in the OFF position do the same with the others as well there are 3 coils all together...you should have readings between 5 an7 thousand ohms if so the secondary side of the coils are good, if there is no spark at all try an ignition module. this is under the 3 coils they sit on the ign module..You can also test and or replace the spark plug wires, if a wire is 10 inches long it should read 10,000 ohms or less.. No more than 1000 ohms per inch is the spec.. hope this helps good luck

3.1L Engine

1. Tag and disconnect the two plug wires attached to the suspected coil.
2. Remove the two screws securing the ignition coil to the Ignition Control Module (ICM).
3. Remove the ignition coil.
4. Before testing, visually inspect the coil for carbon paths or cracks which will contribute to weak spark symptoms.
5. Using an ohmmeter, check the resistance between the primary terminals on the underside of the coil. The resistance should be 0.50-0.90 ohms.
6. Check the resistance between the secondary terminals. It should be 5,000-8,000 ohms.
7. If the coil failed either test, it must be replaced.

540 ohm

Don't know the actual resistance but the general resistance I use that has not let me down is 1000 ohms per foot and not more than 10,000 ohms on any wire.

the specs are pretty easy to find (I don't happen to have them handy, but they are on several websites). You can test them in place with a volt/ohm meter, but you need to have the ignition on for at least one of these tests.

Mine fails when the engine gets hot- both the igniter and the coil seem very heat-sensitive, and one of my cylinders has a leaky exhaust valve that causes some heat problems.

Be careful when testing, that any removed wires don't touch anything. I had to replace part of a wiring harness for that reason.

Also, consider pricing a complete distributor instead of the component parts.

Good luck, -Joe