# 1986 Ford thunderbird turn the key and it starts but wont stay running!HELP

**URL:** <https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246>\
**Category:** Maintenance/Repairs\
**Tags:** thunderbird, ford\
**Created:** [March 25, 2013, 2:07am UTC](https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246 "2013-03-25T02:07:18Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![Fordfan1986](https://avatars.discourse-cdn.com/v4/letter/f/53a042/32.png) [@Fordfan1986](https://community.cartalk.com/u/Fordfan1986)\
**Post date:** [March 25, 2013, 2:07am UTC](https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246/1 "2013-03-25T02:07:18Z")

</div>

Okay i have my car and it takes a few times to start but once its on it wont stay running if i let go of the key or the ignition cylinder help me!!!

---

<div class="post-metadata">

**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [March 25, 2013, 2:21am UTC](https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246/2 "2013-03-25T02:21:38Z")

</div>

The problem could be caused from a faulty Ignition Control Module.

The ICM functions in two modes. These are the Start and the Run modes. When starting the engine the ICM allows full battery voltage the coil. This ensures the cold engine with a rich fuel mixture starts. Once the engine starts and the ignition switch moves to the run position the ICM switches to the Run mode. The ICM then steps the voltage down to the coil so that the charging system voltage doesn’t burn up the coil and the other secondary ignition components.

So it could be that the Start mode of the ICM is working, but the Run mode of the ICM has failed.

Tester

---

<div class="post-metadata">

**Author:** ![Fordfan1986](https://avatars.discourse-cdn.com/v4/letter/f/53a042/32.png) [@Fordfan1986](https://community.cartalk.com/u/Fordfan1986)\
**Post date:** [March 25, 2013, 3:07am UTC](https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246/3 "2013-03-25T03:07:02Z")

</div>

The ingnition lock cylinder is broken and it wont turn its locked and when we would start it if i let it go it would just shut off so im really just thinking its the lock cylinder

---

<div class="post-metadata">

**Author:** ![Cavell](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cavell/32/43396_2.png) [@Cavell](https://community.cartalk.com/u/Cavell)\
**Post date:** [March 25, 2013, 4:27pm UTC](https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246/4 "2013-03-25T16:27:44Z")

</div>

oh, i forgot to mention the lock cylinder is broke. ugh, that might affect starting. duh

---

<div class="post-metadata">

**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 25, 2013, 10:10pm UTC](https://community.cartalk.com/t/1986-ford-thunderbird-turn-the-key-and-it-starts-but-wont-stay-running-help/78246/5 "2013-03-25T22:10:14Z")

</div>

OK, this was just a test.