Honda  |   If a spark is present, the ignition coil is working properly. If a spark is present, the spark plug is working properly. More specifically, this article is designed to help you troubleshoot a bad Coil-On-Plug (COP) ignition coil with step-by-step testing instructions. Turn the lawn mower's ignition switch on and pull the rope to spin the flywheel. Use an extra spark plug. They may be immediately apparent, or hidden under an engine cover, or beneath pipework. An absence of spark will require replacement of the ignition coil. Inspect the original spark plug after removing it. How to remove a spark plug. Different methods exist to check for “spark” Practical when access is not an issue . Testing Continuity The ignition coil consists of a single wire wound hundreds of times around a core, and any break that occurs in the wire renders the coil inoperable. To test these circuits, it's not necessary to unplug the ignition coil's connector. The testing of these two circuits is done in part while the engine is being cranked. Then start the engine and watch the tester window. Locate the ignition coil, or coils, on your vehicle. Insert a spark plug tester into the plug boot and ground it on a piece of metal on the engine. The tool is installed inline with the ignition coil to determine if the coil is producing a spark. Terms of Use The coils then convert the energy to a higher voltage, of atleast 50,000 volts, in order to create a spark. Here is a fast easy method to diagnose if your spark plug is the problem. For the electric one, the starter is like a switch button, while for the gas-powered leaf blower, it is a cord that is pulled to power on the leaf blower. This is a first generation (1998) Toyota RAV4, which I believe means they are the coil-on … Using An LED Light To Test The Coil-On-Plug. Touch the test probes together to determine the existing resistance in the test leads, then hold one test probe on one terminal, the other probe on the other terminal, this wire show’s 10,000 ohms, which by … A spark plug tester. Insert a spark tester tool or a replacement working spark plug into the spark plug wire. © 2011-2020 Abraham Torres-Arredondo 2) That the spark plug does not have its porcelain insulator cracked. It'll be necessary to disconnect the COP coil from its electrical connector to remove it. There are several ways to find out if the COP ignition coil on your Ford 4.6L or 5.4L is bad or not. If you want to know why I recommend the HEI spark tester, go to section: Why The HEI Spark Tester. The coil looks like a black cylinder with a center wire similar to … As I've already mentioned, the type of Coil on Plug ignition coil that we'll be testing has two wires in its connector. If the engine has a coil-on-plug ignition system with no plug wires: Remove one of the coils from the spark plug. How can you check for power and the switching signal? Locate the coil on your Ford engine. You can find the blower motor in any auto parts store. Now, have your helper crank the car (or pick up or van) as you watch the HEI spark tester (from a safe distance). Ford  |   A coil with three wires has one for power, one for ground and one that carries the command signal from the PCM that operates the coil’s internal switching transistor. such an exposed metal area. How To: Use a lab scope and inductive pickup to test a coil on a car spark plug ; How To: Remove the ignition coil & module in a Saturn S-Series ; How To: Use a shortcut to quickly remove a heater core on a 2001 Ford Taurus ; How To: Install 120 Volt Plugins & USB Ports in a Car or Truck ; How To: Change out the spark plugs on your car If you suspect that your Toyota has a bad COP ignition coil that's causing a misfire condition (and setting a misfire code that is lighting the check engine light (CEL)), then this is the tutorial you need. The starter is located on the outside part of a leaf blower. Hold the plug wire using insulated pliers, and allow the bare end of the spark plug to touch a grounded surface. A wire connecting the coil to the spark plug conducts a current to the plug terminals, which results in the spark that ignites fuel in the combustion chamber. If the electrodes are damaged or worn, replace the spark plug. The other is without one and requires that you swap the some COP coils to find out. Please read the following sections: I Have a Misfire Code(s) or I Have NO Misfire Code(s) before jumping into COP COIL TEST 1. These ignition coils are known technically as Coil-On-Plug (COP) ignition coils. Pull the rope to spin the flywheel and watch for a spark on the original spark plug. Try to remove the spark plugs by hand the ensure the plugs are properly seated. By creating an account you agree to the Hunker, Repair FAQ: Determining Why It Won't Start, Youtube: Lawn Mower Repair Ignition Coil Test. When he is not managing the parts department of a local, multi-line motorcycle dealership, Gilliland can often be found riding, writing or working on his motorcycle blog, Wingman's Garage. If you're wanting the buy the original Ford Motorcraft ignition coil, you can buy it online for a whole lot cheaper than somewhere local. To test the operation of both the ignition coil and the spark plug, connect the tester between the spark plug boot and the spark plug. Use your volt meter to touch the power wire and the trigger wire. I'm gonna' explain both in this article. While checking for a clogged air filter or filling the fuel tank requires little thought, determining if the ignition coil is creating the electrical spark needed to burn the air and fuel can be puzzling. Coil-on-Plug (COP): You will recognize these coils immediately as they sit directly on top of the engine’s valve or cam cover, are bolted down, and attach directly to the spark plug via a rubber boot. Wrap a short length of rope around the motor's flywheel, the round disk-shaped piece above the motor. Step 2: Locate the ignition coil, or coils, on your vehicle.. CASE 2: You got NO spark. That antifreeze isn't leaking into the spark plug well. If you haven't read the sections: I Have Misfire Codes or I Have NO Misfire Codes, please do so now. This article will help you to diagnose a misfire condition lighting up the check engine light on your 4.6L or 5.4L Ford vehicle with the following misfire diagnostic trouble codes: P0301, P0302, P0303, P0304, P0305, P0306, P0308. Watch the spark tester or spark plug, looking for a spark between the electrodes of the tester or spark plug. As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. Ensure the spark plug wires are properly connected. Though its precise location may vary from vehicle to vehicle, generally, it is located near the fender or bolted to a bracket fairly close to the distributor. Spark tester tool or a working spark plug. An absence of spark from just ONE ignition coil points to a … My bi… If the coil has more than two wires, you’ll need a wiring diagram to determine how to test it. Pull the spark plug cable off of the spark plug and remove the spark plug. Older vehicles have a distributor, ignition coil, and spark plug wires. Ignition coils retrieve energy from the battery, which is usually at least 12 volts. Removing the HT lead, or coil on plug will reveal the base of the spark plug. For more info (and photos) on these possible conditions, see section: Other Misfire Causes. Luckily, testing the spark plug and ignition coil can be easier than it seems. You can also deduce, from this result, that the ignition coil pack and the spark plug wires are OK. Inspect the entire wire, from the plug to the magneto beneath the armature plate. An absence of spark will require replacement of the spark plug. Locate the ignition coil on the motor by following the spark plug cable to the coil. Required Tools for this Ignition Coil Test Project Don't worry, once you get to the site they'll make sure it fits (by asking you the specifics of your particular Ford vehicle). Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem! How to test a spark plug: Step 08 With the engine cold locate the plugs. An ignition coil is a kind of high-voltage transformer. Coil packs usually create a better spark, which in turn produces better combustion and horsepower in a car's engine. Spark plug wire kit for C.O.P. Most vehicles made after the late 1990s typically have a small ignition coil that sits directly on top of each spark plug, which is known as coil-on-plug (COP) design. Here's why: The COP coil that you just tested (and that didn't spark) receives power in the form of 12 Volts DC and a switching signal that comes directly from the PCM (Powertrain Control Module= Fuel Injection Computer). Coil-on-Plug (COP) Ignition Coil Misfire Tests (Ford 4.6L, 5.4L). After taking out the spark plug, attach the plug wire back. Jeep  |   Now, you don't have to read the entire article to use the info presented here but, I suggest you do. You will detach the wire either at the coil pack or at the distributor cap … Using a battery jump start cable, Ground the HEI spark tester to the battery negative (-) terminal. If a spark jumps from a plug wire to the test light at any point, this is an indication that the insulation has broken down, and the spark plug wire should be replaced. How To Test The Fuel Injectors (1999-2000 4.6L Crown Victoria), How To Test The Fuel Injectors (1998 4.6L Crown Victoria), How To Test The Fuel Injectors (1992-1997 4.6L Crown Victoria), “I never made a mistake in my life. Ground the spark tester or spark plug by placing it directly against the motor's metal housing. This means that the cause of the misfire code and misfire condition is not due to a lack of spark. I've found plenty of resources on inspecting the condition of spark plugs after removing them, and to do with diagnosing misfiring spark plugs, but not a test for a simple yes-no, are they firing at all or aren't they. Removing and replacing spark plugs is very simple – getting to them, on some engines, can be a little tricky. Inspecting the Spark Plug Wires with the Engine Off Look for physical damage to the wires or boots, … This is the easiest and the most effective way of getting at the signals. An avid motorcyclist, Chris Gilliland has immersed himself into the two-wheeled world while balancing work life and raising three daughters. TIP 3: You'll notice that the photos and the testing instructions call for an HEI spark tester. 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009. Remove wires from coil. Coils are sensitive to heat and may produce an intermittent problem if their internal components become weak. Testing these circuits can … What the Coil Does . A screwdriver is a quite quick way to test if the … You can also test an ignition coil with a spark tester. These coils boost magneto voltage high enough to ignite the fuel/air mixture in the cylinder by jumping the gap between the spark plug electrodes. Chrysler  |   Use a spark plug wrench to remove the plugs, one at a time, and tag them to identify the cylinder in which they were installed. My biggest suggestion to you is to have your helper wait outside the vehicle as you set up the test to avoid having him or her crank the engine accidentally. Remove the spark plug wire. Turn off the ignition switch and remove the spark plug or spark tester from the spark plug wire. IMPORTANT: Before you start, read the following first:TIP 1: The very first thing you have to do, before you start testing with the info in this article, is to find out which cylinder or cylinders are misfiring. If it doesn't fit, they'll find you the right one. As with most types of vehicular maintenance, you'll want to begin the test with the vehicle in park and with the engine off. Rewind the rope around the flywheel and turn the lawn mower's ignition switch on. You can use the tester on any small engine (mower, snow blower, chain saw, string trimmer, etc.). With a few basic items you can quickly determine the health of your mower's ignition system. If there’s a fourth wire, that one sends a firing confirmation signal to the PCM. The easiest and best method to pinpoint a problem on these coils is to do the #1 method of swapping the coil with a neighboring coil to see if the misfire moves to a different cylinder. If you don't have one, you can use any other type of spark tester (although the results may not be as accurate). How a Coil Pack Works. You'll notice that the photos and the testing instructions call for an HEI spark tester. An uncooperative lawn mower may have a bad ignition coil or spark plug. If you're testing multiple cylinders, repeat steps 1 thru' 4 on the other COP coil that the misfire code has identified as misfiring. Ground the … Disconnect the ignition coil's kill switch wire by pulling the wire directly off of the coil. Open the lawn mower's hood or cover to access the ignition coil. A faulty coil may fire intermittently, produce a weak spark or kill a cylinder completely. Attach the test light to a good engine ground. These are usually located right on the engine, either … What I recommend you do is to test for each signal with the connector connected using a wire-piercing probe. Place the original spark plug back in, and set the spark plug wire against the motor. All three components (flywheel, spark plug, and ignition coil) are found in the engine. testing . The rope will allow you to rotate the flywheel at a greater speed than spinning it by hand. I thought I did once, but I was wrong.”Charles M. Schulz, Home  |   A spark plug misfire will immediately be evident in the tester window. Finally, Have someone crank the engine and watch for spark. The following testing instructions assume that you already have a specific cylinder in mind to test: Remove the Coil-On-Plug (COP) coil that you need to test. How To Check Spark Plug Fire With A Screwdriver. 3.) To help you effectively use this test article, read the following CASES and follow the one that applies to your specific testing situation/ needs. When creating a spark at the spark plug, the fire must initiate from a high voltage supply, so as much fuel as possible burns in the cylinder. GM  |   Although manufactured to last, ignition coils … Do NOT follow this link or you will be banned from the site! Please read the following sections: I Have a Misfire Code(s) or I Have NO Misfire Code(s) before jumping into COP COIL TEST 1.TIP 2: Most of the testing, that you'll be doing, is done with the engine cranking... so be careful and stay alert. One is using a spark tester and is the most accurate way of testing for a bad Coil-On-Plug (COP) ignition coil. Note: If all of the ignition coils aren’t delivering spark, the issue is likely with the control side (primary side) of the ignition system, rather than a single ignition coil. OK, let's take a look at what your test results mean: CASE 1: You got spark. If this one sparks, then you know beyond a shadow of a doubt that the COP coil is getting both power and the switching signal, therefore it's bad and needs to be replaced. First, you should test the coils with a multimeter. It converts the power from your car's 12-volt battery into the thousand or so volts that the spark plugs need in order to fire and then ignite the engine's air-fuel mixture. Fortunately, the task is made easier by the relative simplicity of most lawn mowers' small engines. This test result usually means that the COP coil is fried, but not always. Summary. Tools  |   Each spark plug will have an HT lead, (on older cars) or a coil on plug attached to the top of it. This energy then travels via the distributor to the spark plugs, and then ignites the fuel. Secondary testing with scope . spark plug and the spark plug boot do not have carbon tracks. There are three main ingredients to starting and operating a lawn mower: air, fuel and spark. The HEI spark tester will give you one of two possible results: spark or no spark. Hunker may earn compensation through affiliate links in this story. All Rights Reserved. This can easily be done by simply substituting another COP coil (that is sparking and that is not setting a misfire code) and checking if this one sparks with your spark tester. The following links will help you comparison shop for the Ford Motorcraft and after-market ignition coils: Will the above ignition coils fit your particular Ford pickup (car or SUV)? DIAGNOSTIC TEST OPTION 1: You have a spark tester and plan to troubleshoot the COP coils with it, start at COP COIL TEST 1. Turn the vehicle off and open the hood. Disclaimer. Removing either the High Tension Leads (also known as Spark Plug Wires), or for cars with a 'Coil-On-Plug' (COP) set-up removing the ignition coils. With the engine running, move the test light along the length of each spark plug wire. If any of these two are missing, the COP coil won't spark and you just might replace something that will not solve the misfire problem/issue. TIP 2: Most of the testing, that you'll be doing, is done with the engine cranking... so be careful and stay alert. Once the winding inside weakens or breaks, the problem is irreversible. If you don't have one, you can use any other type of spark tester (although the results may not be as accurate). Use a Spark Tester . Open the hood to locate the ignition coil. Chainsaw, lawn mower or weedeater won't start or spark plug has no spark? If you want to know why I recommend the HEI spark tester, go to section: Why The HEI Spark Tester. However, you can test the coil pack on your car using a voltmeter. DIAGNOSTIC TEST OPTION 2: You don't have a spark tester, start here: COP COIL TEST 2. Refer to your lawn mower's owners manual for ignition coil locations and installation/removal information. The first thing you need to do, is to see if the COP coil is sparking and this test step will help you with this. The locking tab on the connector breaks very easily... so be careful unplugging it from the coil. C.O.P. The ignition coil transforms the battery’s voltage to a level that allows the spark plug to do its job. Insert a spark tester tool or a replacement working spark plug into the spark plug wire. IMPORTANT: Before you start, read the following first: TIP 1: The very first thing you have to do, before you start testing with the info in this article, is to find out which cylinder or cylinders are misfiring. Take help from your partner or someone else, and ask them to start the ignition. I suggest that you verify that the COP coil is getting power and its switching signal before you replace it. Set it aside for now. I suggest that you check to see that the 1.) 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