# Check Engine light won't turn off - even though repair most likely accomplished **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [May 8, 2011, 5:37pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496 "2011-05-08T17:37:21Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![madmilt](https://avatars.discourse-cdn.com/v4/letter/m/7feea3/32.png) [@madmilt](https://community.cartalk.com/u/madmilt)\ **Post date:** [May 8, 2011, 5:37pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/1 "2011-05-08T17:37:21Z")
2004 Ford Focus, 2 Liter Zetec engine. 0. Situation: Car initially running well but want to improve mileage, so I installed premium plugs. 1. Ran roughly on test run, so headed home. Check Engine light came on before fully warmed up. 2. Found and corrected loose plug wire. 3. Engine now purrs like a kitten, but Check Engine light stays on. What should I do now? ---
**Author:** ![bedrock](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bedrock/32/868_2.png) [@bedrock](https://community.cartalk.com/u/bedrock)\ **Post date:** [May 8, 2011, 5:44pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/2 "2011-05-08T17:44:32Z")
if you don;t have a scan tool go by auto zone or advance auto they will cut it off free of charge. ---
**Author:** ![chaissos](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/chaissos/32/2347_2.png) [@chaissos](https://community.cartalk.com/u/chaissos)\ **Post date:** [May 8, 2011, 5:49pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/3 "2011-05-08T17:49:30Z")
You should note the codes just in case they come back. The exact codes, and not what they think may be wrong. ---
**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\ **Post date:** [May 8, 2011, 6:59pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/4 "2011-05-08T18:59:18Z")
Most Fords will reset if you disconnect the battery for a minute or so… ---
**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:** [May 8, 2011, 7:20pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/5 "2011-05-08T19:20:44Z")
It takes three drive cycles with out a DTC to turn off the check engine light. If you haven’t done the three complete cycles, have patience. If it doesn’t go out after three drive cycles, then get the code(s) read and report them back here. It is remotely possible that you knocked a vacuum line or a connector loose or something. ---
**Author:** ![Joseph\_E\_Meehan](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/joseph_e_meehan/32/21_2.png) [@Joseph\_E\_Meehan](https://community.cartalk.com/u/Joseph_E_Meehan)\ **Post date:** [May 8, 2011, 9:39pm UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/6 "2011-05-08T21:39:43Z")
I agree with keith here. ---
**Author:** ![piter\_devries](https://avatars.discourse-cdn.com/v4/letter/p/aca169/32.png) [@piter\_devries](https://community.cartalk.com/u/piter_devries)\ **Post date:** [May 9, 2011, 12:06am UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/7 "2011-05-09T00:06:19Z")
How do “premium plugs” improve gas mileage? ---
**Author:** ![lion9car](https://avatars.discourse-cdn.com/v4/letter/l/59ef9b/32.png) [@lion9car](https://community.cartalk.com/u/lion9car)\ **Post date:** [May 9, 2011, 12:51am UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/8 "2011-05-09T00:51:16Z")
A lot of people have issues with plugs that aren’t OEM. I’d go back to the OEM plugs myself. ---
**Author:** ![madmilt](https://avatars.discourse-cdn.com/v4/letter/m/7feea3/32.png) [@madmilt](https://community.cartalk.com/u/madmilt)\ **Post date:** [May 9, 2011, 2:35am UTC](https://community.cartalk.com/t/check-engine-light-wont-turn-off-even-though-repair-most-likely-accomplished/64496/9 "2011-05-09T02:35:18Z")
Thank you everybody. Caddyman’s suggestion worked.