Ignition coil how do I check the intensity of the strength of the spark on the ignition coil? no ohmeter available

The spark intensity is most important .Remove all plugs to check gap and condition of plugs. The black plug indication will confirm that the performance is bad whereas a fully fired plug without deposits must be the ideal view. Check the HT coil and the HT wires, if the intensity is bad this must be swapped and checked to confirm. DO NOT CHANGE any part without a confirmation by trying with a replacement from another vehicle or friend. Finally the LT trigger to the coils must be checked be it from the platinum points or an electronic ignition unit. The voltage of the trigger must be high to give the best HT output.

check the voltage to the sections of the coil and ignition unit which if present will confirm the fault on the unit.

Since you have not mentioned the fault experienced I think this must be a poor performance or a poor start up.
If so make sure there is good spark intensity to confirm that the ignition is good. If not check the HT coil and the ignition system, check the LT voltage on the coil.
Also the fuel pump pressure as the filter was changed as it is important for smooth running.

test battery -is it holding 12.6v charge-if not then its over 3 yrs old or the alternator is bad--also inspect inside distributer cap and plug wires--they get corroded and need replacin

A rough idle can be due to poor timing./fuel tuning.So an examination of the spark plug will give the indication of the firing of all the cylinders with which we can confirm . If the spark plugs are burnt then the fuel mixture is good but if there is a black soot or soggy smear then the fuel settings are high or the spark intensity is low.
So you need to check on the fuel pressure-- have the pump calibrated .
Check the spark intensity , it must be good or the HT coils or the electronic ignition is faulty as the trigger can be low. Check also the timing. it is good to have the job done at the service outlet.

The poor performance of the car makes these faults to come up and undermine the working of the engine.Since the fault comes up when the engine is warm you need to check the ignition and the fuel pump.

check the pressure of the fuel pump when the engine is warm, calibrate if the pressure at the injector is low.

Then we must check with the electrics. The spark intensity is most important .Remove all plugs to check gap and condition of plugs. The black plug indication will confirm that the performance is bad whereas a fully fired plug without deposits must be the ideal view. Check the HT coil and the HT wires, if the intensity is bad this must be swapped and checked to confirm. DO NOT CHANGE any part without a confirmation by trying with a replacement from another vehicle or friend. Finally the LT trigger to the coils must be checked be it from the platinum points or an electronic ignition unit. The voltage of the trigger must be high to give the best HT output.

Sometimes coils can go weak when the insulation heats and so check this out . Also the ignition system can fail when the electronics warm up, if so test for spark.

Thank you for using Fixya

There are lots of issues that might relate to the engine not firing and must be checked. So start by checking on the fuel, the fuel filter, the fuel delivery.
next check on the firing , the HT coils the spark intensity. Check the coils and the timing of the spark.
Please check the following tips:

http://www.fixya.com/cars/r5843031-tips_check_car_not_start

Check for spark. Maybe a crankshaft position sensor is bad or a module.

Secondary Spark Test This spark tester looks just like a spark plug, attach the clip to ground and crank the engine to check for spark
This spark tester has an adjustable air-gap for measuring spark strength and testing different voltage ignition systems
Attach the clip to ground and crank the engine to check for spark
This spark tester is the easiest to use just place it on a plug wire and the spark voltage is detected and the bulb on the top will flash with each pulse
The best way to perform this procedure is to use a spark tester (available at most automotive parts stores). Three types of spark testers are commonly available. The Neon Bulb type is connected to the spark plug wire and flashes with each ignition pulse. The Air Gap type must be adjusted to the individual spark plug gap specified for the engine. The last type of spark plug tester looks like a spark plug with a grounding clip on the side, but there is no side electrode for the spark to jump to. The last two types of testers allows the user to not only detect the presence of spark, but also the intensity (orange/yellow is weak, blue is strong).

1. Disconnect a spark plug wire at the spark plug end.
2. Connect the plug wire to the spark tester and ground the tester to an appropriate location on the engine.
3. Crank the engine and check for spark at the tester.
4. If spark exists at the tester, the ignition system is functioning properly.
5. If spark does not exist at the spark plug wire, perform diagnosis of the ignition system using individual component diagnosis procedures.

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Ignition Coil Testing

1. Remove suspect coil.
2. Disable fuel pump by disconnecting inertia switch electrical connector.
3. Reconnect the ignition coil electrical connector to the coil.
4. Install spark tester 303-D307 (D81P-6666-A) or the equivalent.
5. Crank engine while observing the tester.
6. If a blue-white spark is not observed replace coil.

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Removal & Installation To Remove:

1. Remove the air cleaner outlet pipe if interfering.
2. Disconnect the connector from the ignition coil.
   
   
3. Remove the bolt from the ignition coil.
   
   
4. Remove the ignition coil on plug.

To Install:

1. Install ignition coil on spark plug.
2. Install ignition coil bolt. Tighten to 10 Nm (89 in. lbs.).
   
   
3. Reconnect the ignition coil electrical connector.
   
   
4. Install the air cleaner outlet pipe if removed earlier.

Secondary Spark Test This spark tester looks just like a spark plug. Attach the clip to ground and crank the engine to check for spark.

This spark tester has an adjustable air-gap for measuring spark strength and testing different voltage ignition systems.

Attach the clip to ground then crank the engine to check for spark.

This spark tester is the easiest to use. Just place it on a plug wire and the spark voltage is detected; the bulb on the top will flash with each pulse.

NOTE: The best way to perform this procedure is to use a spark tester (available at most automotive parts stores). Three types of spark testers are commonly available:

• The Neon Bulb type is connected to the spark plug wire and flashes with each ignition pulse.
• The Air Gap type must be adjusted to the individual spark plug gap specified for the engine.
• The last type of spark plug tester looks like a spark plug with a grounding clip on the side, but there is no side electrode for the spark to jump.

NOTE: The last two types of testers allow the user to not only detect the presence of spark, but also the intensity of the spark. Orange/yellow is weak, blue is strong.

1. Disconnect a spark plug wire at the spark plug end.
2. Connect the plug wire to the spark tester and ground the tester to an appropriate location on the engine or frame.
3. Crank the engine and check for spark at the tester.
4. If spark exists at the tester, the ignition system is functioning properly.
5. If spark does not exist at the spark plug wire, perform a diagnostic test of the ignition system using individual component diagnosis procedures.

Removal & Installation 2.0L Engine Ignition system components (Code AEG)

Ignition system components (Codes AVH, AZG, BEV)

Timing controls when spark happens ...it does not make spark. make sure coil and all other ignition trigger devices are good (crank sensor, cam sensor, wiring and pcm) You can get info for tests from inexpensive manuals such as chiltons or haynes and using a digital volt/ohmeter.

check crankshaft sensor (left side of bellhousing underneath) DO not buy one first, test it with an ohmeter (specs in any manual) if out of range then change it. Also suspect will be ignition module (if you have one, it's next to the coil. After checking these out, if no results, check cam sensor Inside distributor. That's enough to confuse you for awhile.
Good luck