# 1999 Jeep Wrangler - Jumps, lurches, bucks **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** jeep\ **Created:** [February 11, 2020, 10:01pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334 "2020-02-11T22:01:11Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![NicholasThomo](https://avatars.discourse-cdn.com/v4/letter/n/b2d939/32.png) [@NicholasThomo](https://community.cartalk.com/u/NicholasThomo)\ **Post date:** [February 11, 2020, 10:01pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/1 "2020-02-11T22:01:11Z")
My vehicle lurches, jumps, and bucks while driving. It’s horrible when cold but doesn’t get much better when it warms up. ---
**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:** [February 11, 2020, 11:11pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/2 "2020-02-11T23:11:28Z")
Original shocks? Tester ---
**Author:** ![davepsinbox\_157004](https://avatars.discourse-cdn.com/v4/letter/d/73ab20/32.png) [@davepsinbox\_157004](https://community.cartalk.com/u/davepsinbox_157004)\ **Post date:** [February 11, 2020, 11:38pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/3 "2020-02-11T23:38:13Z")
Is it lurching up and down or front to rear? One is suspension, the other is engine or transmission. ---
**Author:** ![SteveCBT](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/stevecbt/32/3192_2.png) [@SteveCBT](https://community.cartalk.com/u/SteveCBT)\ **Post date:** [February 11, 2020, 11:45pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/4 "2020-02-11T23:45:18Z")
How many miles on it? How old are the plugs, wires, coil? What does the air filter look like? What is the recent maintenance history? ---
**Author:** ![NicholasThomo](https://avatars.discourse-cdn.com/v4/letter/n/b2d939/32.png) [@NicholasThomo](https://community.cartalk.com/u/NicholasThomo)\ **Post date:** [February 12, 2020, 1:02am UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/5 "2020-02-12T01:02:31Z")
Lurching forward ---
**Author:** ![NicholasThomo](https://avatars.discourse-cdn.com/v4/letter/n/b2d939/32.png) [@NicholasThomo](https://community.cartalk.com/u/NicholasThomo)\ **Post date:** [February 12, 2020, 1:03am UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/6 "2020-02-12T01:03:36Z")
Has 188,000 miles ---
**Author:** ![davepsinbox\_157004](https://avatars.discourse-cdn.com/v4/letter/d/73ab20/32.png) [@davepsinbox\_157004](https://community.cartalk.com/u/davepsinbox_157004)\ **Post date:** [February 12, 2020, 1:05am UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/7 "2020-02-12T01:05:12Z")
Has the check engine light come on? If so, have the stored codes read. If not I’d guess transmission. ---
**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:** [February 12, 2020, 3:27am UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/8 "2020-02-12T03:27:52Z")
It sounds like it is misfiring. Any diagnostic codes in computer memory? That’s where to start to get some clues what’s going on. ---
**Author:** ![NicholasThomo](https://avatars.discourse-cdn.com/v4/letter/n/b2d939/32.png) [@NicholasThomo](https://community.cartalk.com/u/NicholasThomo)\ **Post date:** [February 12, 2020, 3:04pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/9 "2020-02-12T15:04:13Z")
That’s what I’m thinking thank you ---
**Author:** ![ledhed75](https://avatars.discourse-cdn.com/v4/letter/l/f6c823/32.png) [@ledhed75](https://community.cartalk.com/u/ledhed75)\ **Post date:** [February 12, 2020, 9:40pm UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/10 "2020-02-12T21:40:40Z")
Is it 4WD with a transfer case? I wonder if it might be slipping into 4WD periodically. Just an idea. ---
**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:** [February 13, 2020, 2:00am UTC](https://community.cartalk.com/t/1999-jeep-wrangler-jumps-lurches-bucks/158334/11 "2020-02-13T02:00:33Z")
> [@NicholasThomo](#): > > [misfiring] is what I’m thinking If so there should be some p030x diagnostic codes. The computer is an expert at detecting misfiring.