# Lightning and speedometers **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** speedometer\ **Created:** [July 1, 2008, 1:27am UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081 "2008-07-01T01:27:18Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Jargon](https://avatars.discourse-cdn.com/v4/letter/j/ad7895/32.png) [@Jargon](https://community.cartalk.com/u/Jargon)\ **Post date:** [July 1, 2008, 1:27am UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/1 "2008-07-01T01:27:18Z")
I was driving home last Friday and drove through a huge thunder, lightning and rain storm. All of a sudden my speedometer jumped from 55mph to 80mph but I wasn’t going any faster. I slowed down and pulled over. Everything seemed fine so I drove the rest of the way home. The car is driving just fine now and the speedometer is acting normally. I drive a 2002 Subaru Forester. Has anyone had this happen to them? Thanks ---
**Author:** ![bobbyandberyl](https://avatars.discourse-cdn.com/v4/letter/b/bbce88/32.png) [@bobbyandberyl](https://community.cartalk.com/u/bobbyandberyl)\ **Post date:** [July 1, 2008, 2:31am UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/2 "2008-07-01T02:31:31Z")
Did you have cruise control engaged? Sounds like hydroplane to me. Even without cruise control you could have the same experience. I’ve had this happen to me dozens of times over the years. ---
**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:** [July 1, 2008, 11:54am UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/3 "2008-07-01T11:54:35Z")
Good call. OP = Check there tyres. If they are worn it is time for new ones. You may have been very lucky. ---
**Author:** ![bobbyandberyl](https://avatars.discourse-cdn.com/v4/letter/b/bbce88/32.png) [@bobbyandberyl](https://community.cartalk.com/u/bobbyandberyl)\ **Post date:** [July 1, 2008, 12:23pm UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/4 "2008-07-01T12:23:20Z")
While the culprit in hydroplane is often worn tires, it also can easily happen with perfectly good tires. The problem is acceleration while passing through standing water on the highway. Use gentle acceleration when the roads are wet and most importantly of all … slow down. It’ll probably save your life one day. As Mr Meehan states, quite rightly, you may have been very lucky. ---
**Author:** ![NYBo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nybo/32/17281_2.png) [@NYBo](https://community.cartalk.com/u/NYBo)\ **Post date:** [July 1, 2008, 12:50pm UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/5 "2008-07-01T12:50:31Z")
Hydroplaning, yes. Caused by cruise control, very unlikely. The cruise control would have detected the increased wheel speed and cut the throttle accordingly, faster than most drivers could. But cruise control use in bad weather isn’t a good idea regardless. ---
**Author:** ![Jargon](https://avatars.discourse-cdn.com/v4/letter/j/ad7895/32.png) [@Jargon](https://community.cartalk.com/u/Jargon)\ **Post date:** [July 3, 2008, 1:57am UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/6 "2008-07-03T01:57:00Z")
The cruise control button was on but cruise was not set - it wasn’t raining when I started driving. I have good tires. From your posts, I’m guessing I was hydroplaning. I was going slower than most drivers, but next time I’ll go even slower. Actually, next time I’ll get off the highway and take the local roads. The rain just started coming down in buckets - quite a scarey feeling and one I have no wish to repeat. Thank you all! ---
**Author:** ![NYBo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nybo/32/17281_2.png) [@NYBo](https://community.cartalk.com/u/NYBo)\ **Post date:** [July 3, 2008, 3:18am UTC](https://community.cartalk.com/t/lightning-and-speedometers/16081/7 "2008-07-03T03:18:20Z")
Could it be you have those Bridgestone Potenza R92s that Subaru tends to use as OE, the ones a number of posters here have descried as terrible in any kind of bad weather?