# How do I not overtighten or undertighten spark plugs for a 2002 Corolla? **URL:** \ **Category:** General Discussion\ **Created:** [March 13, 2016, 10:25pm UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763 "2016-03-13T22:25:01Z")\ **Posts on this page:** 9\ **Page:** 2
**Author:** ![Volunteer871](https://avatars.discourse-cdn.com/v4/letter/v/839c29/32.png) [@Volunteer871](https://community.cartalk.com/u/Volunteer871)\ **Post date:** [March 18, 2016, 5:38am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/21 "2016-03-18T05:38:15Z")
I have NGK plugs. Should I use dielectric grease but not anti-seize compound? They are BKR5EIX-11 stock #5464. ---
**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\ **Post date:** [March 18, 2016, 6:14am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/22 "2016-03-18T06:14:39Z")
It takes quite a but of force to cross thread a spark plug, you are deforming metal. You can’t cross thread a spark plug using your fingers. Using reinforced tubing will slip with very little force, far far less force than required to cross thread the plug. If it is going in with just tubing, reinforced or otherwise, then it is not cross threaded. ---
**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\ **Post date:** [March 18, 2016, 6:17am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/23 "2016-03-18T06:17:14Z")
The dielectric grease goes on the inside of the boot for the spark plug wire, or in your case, the connector between the coil and the plug. It seals the connection and prevents any arcing outside of the boot. If any grease gets on the metal parts of the connection, it will not do any harm. ---
**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\ **Post date:** [March 18, 2016, 6:26am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/24 "2016-03-18T06:26:39Z")
You should have gotten the IFR5T11, 4996 plug, it is the OEM. It will outlast the one you got because it not only has an iridium tip on the cathode, it has a platinum pad on the anode. Yours does not have the platinum pad on the anode so the anode will erode away quicker. The plug you bought is good for 40-60k miles, the correct one will go for 120k easily. ---
**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\ **Post date:** [March 18, 2016, 6:36am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/25 "2016-03-18T06:36:45Z")
I recommend against any type of lubricant on the plug threads. I support Keith’s recommendation. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 18, 2016, 6:54am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/26 "2016-03-18T06:54:39Z")
Dielectric grease (DEG) is an electrical insulator and wouldn’t normally be used on surfaces that require electrical conduction, for example spark plug threads, which must conduct electricity to the engine grounding system for the spark plug to fire correctly. As posted above, DEG can be used on the boots as it will help prevent the boot from sticking to the ceramic portion of the plug. It also helps prevent unwanted high voltage current paths from forming, like down the outside surface of spark plug, which could short out the plug and cause a misfire. This seems unlikely to happen, and has never happened to me even though I don’t use dielectric grease on the boots. But that’s a theory I’ve heard. A note to the OP on torque values. Remember there’s a big difference between inch-pounds and foot- pounds. Spark plugs in aluminum heads tend to be in the 10-12 foot pound range. You don’t need a fancy torque wrench, no electronics required, just one that can measure in that range. ---
**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\ **Post date:** [March 18, 2016, 8:10am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/27 "2016-03-18T08:10:43Z")
Dielectric grease on the threads won’t cause a problem with conduction as the grease will get squeezed so thin when the plugs are tightened, it will conduct. The problem with dielectric grease, or any type of oil or oil based grease without a metal oxide filler is that even silicone grease has a coking temperature and the spark plugs get very hot. The heat could cause the grease to get very thick, forming a sticky sludge that would make removing the plugs later very difficult. Most of the boots on spark plugs is made from silicone so they don’t often harden up like they did in the old days. They used to harden up and crack, then the spark would jump from the contact to the block next to the plug instead of getting to the tip of the plug. The grease would help keep them pliable and if they did crack, it would serve as a backup insulator. I still use the grease today, even if it might not be as necessary as it once was. ---
**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\ **Post date:** [March 18, 2016, 8:15am UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/28 "2016-03-18T08:15:10Z")
If you are not sure if they are tight enough, you do not want to take them out after the gasket was crushed unless you have a torque wrench. Put your hand over the head of the ratchet and grip it there. With just one hand in that position, turn the ratchet tightly. For most people that is about 25 ft/lbs of torque. A little less with a 3/8’ drive ratchet, but about that with a 1/2" drive ratchet. ---
**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\ **Post date:** [March 18, 2016, 7:00pm UTC](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763/29 "2016-03-18T19:00:33Z")
The tubing extends your reach so you can start them by hand and feel if they are going in correctly.You can feel if they are wrong or the tubing will simply slip if crossthreading, unlike a socket and ratchet… [Previous page](https://community.cartalk.com/t/how-do-i-not-overtighten-or-undertighten-spark-plugs-for-a-2002-corolla/92763.md?page=1)