Features:

  • Simple, high quality tool designed to test high energy electronic ignition (HEI) systems
  • Simply attach plug wire to end then use built in clip to attach to ground
  • Tester will give you true spark performance results, helping you identify ignition anomalies that simply removing a plug and grounding it won't reveal
  • For use on vehicles and power equipment equipped with a high energy ignition system
  • Lifetime limited warranty
It works.

My spouse was on a work trip and when I tried to move his car, it wouldn't start. I worked on it for a couple days and the symptoms were pointing to the distributor, so I ordered this tool to test it. When my spouse returned home, I hooked it up and had him get behind the wheel and crank the engine. Naturally, the engine started on the first try. Of course. But in any event, the spark tester worked perfectly and I could easily hear the thing ticking away even over the sound of the engine.

Professional Mechanic here

I own an automotive repair facility that employs 3 other technicians and I have been using spark testers for over 30 years and I have tried them all: 1. The plastic encapsulated ones (not reliable or accurate) 2. The "In Line" type - NEVER - NEVER USE THESE!! It only takes around 10,000 volts to "light" those up - but todays cars need upwards of 50,000 volts so you'll have a "light" but not enough volts to fire the spark plug. 3. I have had 2 OTC 6589's in my box for 20 years - they ALWAYS work AND tell the TRUTH! Yes, I have played around with the others and ALL OF THE DIFFERENT STYLES OF THE FIRST 2 I LISTED HAVE CAUSED ME TO MISS A DIAGNOSTIC. (Hence - cost me productivity time & money) But, when I am in doubt, I grab my OTC and PROVE IT! I NO LONGER USE OR ALLOW IN THE SHOP ANY OTHER SPARK TESTER THAN AN OTC. When I am diagnosing a V-6, V-8 or V-10 motor, I use 2 of these at the same time - one on each side of the motor. Sadly, I dropped one and it being porcelain - it broke (just like a regular spark plug would) So I just ordered 2 more today to keep in my shop. By the way--- the KD 2757 that "LOOKS" the same as the OTC one DOES NOT!!! They changed the design and it is now "plastic encapsulated" and not as accurate. (Same design as the KD 2756) Yes - the OTC is more expensive but this is truly a case of " YOU GET WHAT YOU PAY FOR!" Update: Something I forgot to mention - the clips on these are as heavy duty as they could make them with the amount of material they have to work with. I don't use the clips on the tester itself (yes, they break) I use a 3 foot jumper wire I made out of common "lamp cord" with alligator clips on each end. (it's flexible, heavy duty and rated for 25 amps) (also see: Kastar Hand Tools (KAS1138) 2 x 30' Magnetic Retractable Test Leads - 10 amp rating) I clip one end of the jumper wire to the spark tester clip and the other end to the CLEAN Negative post on the battery - not any metal on the engine itself. If you don't "KNOW" that you have a good ground (rust, corrosion, bad ground from battery to engine block) then you could make a false diagnostic not due to the spark tester operation but because you didn't have a good ground path for the current. Whenever I am testing electrical, I NEVER ground to the frame or body - I always run a jumper wire to the battery negative post - and make sure the negative battery post is clean!

highly recommended

a must have tool in every mechanic's tool box. It has saved me hours and hours of trying to figure out where a misfire is coming from. I've had coil packs that would produce spark when grounded out on a bolt, but with this tool, they were totally dead. Swapped them out with known to be good ones and boom, problem solved. I've used it on several different cars and trucks and it has been a life saver. I use jumper cables to make sure I have a good ground so that A) the clip doesn't break as it is a bit on the flimsy side and B) so I have space to work. I'd buy this tool again and again.

Cheap and nice

Chevy Vortec engines need special equipment like this to test the spark plugs. It is cheap and reliable. Remove the spark plug wire from the spark plug and install it on the tester's spark plug. Clip the clip to a reliable ground, preferably a wire connected to the battery negative. See the solid spark when the engine runs. Use the information gained to determine if you have problems in the ignition.

Awesome tool, more important than you might think.

Excellent tool, I don't even consider using a screwdriver or additional spark plug to test coils, a real test anymore. Coils sometimes like to get weak over time, and cause occasional misfires. You can't really test if it's 20% weaker than its supposed to be. It will still appear to be a good spark. Unless you use the OTC spark tester, it requires the coil to output a much higher voltage. Similar to under high load conditions. Sounds like I'm trying to sell this tool, but it saved me a lot of time today on a Ford 5.4 with 4 coils that didn't pass on the tester. They all had decent spark but not enough apparently. Replaced all 4 of the ones that tested bad, and now it runs great. There's no other way I would have known that. The only issue I've had with it is the end that snaps into the spark plug wire kept unscrewing over time, a little loctite should keep it in place though. Also the porcelain can get dirty, I use brake cleaner and a clean paper towel or q-tip to wipe it clean again. I bought this about 2 years ago, it's helped me a lot but really saved me today. I paid $13.84 here on Amazon. Paid for itself over and over.

Best way to check for spark

The fastest and easiest way to check for spark. I love this, this is usually the first thing I grab and stuck on a vehicle when I get a non running condition

Easy to use

I like this device. It's straightforward. I may not have to use it frequently but it's good to have it when I need to check for spark.

Looks nicely made

Haven't had time to use this yet, but looks to be nicely made. I feel its overpriced for what it is. But, if it helps me find the misfire it will pay for itself.

Spark Tester

Works quite well, I have used it on my 2005 Ford Focus. The coil on spark plug coils had a large and audible snap to them.

Works great

My old truck wouldn't start and I was having a hard time determining if it was getting fire. After putting this little dude between the spark plug and the plug wire I could see that it wasn't getting spark so I knew to look elsewhere for the problem. This spark tester is well made and will last forever.

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