# Hesitation in mornings

**URL:** <https://community.cartalk.com/t/hesitation-in-mornings/37316>\
**Category:** Maintenance/Repairs\
**Tags:** gmc, 1500\
**Created:** [September 29, 2009, 3:51pm UTC](https://community.cartalk.com/t/hesitation-in-mornings/37316 "2009-09-29T15:51:44Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![carhelp199](https://avatars.discourse-cdn.com/v4/letter/c/3be4f8/32.png) [@carhelp199](https://community.cartalk.com/u/carhelp199)\
**Post date:** [September 29, 2009, 3:51pm UTC](https://community.cartalk.com/t/hesitation-in-mornings/37316/1 "2009-09-29T15:51:44Z")

</div>

For the past 2 mornings, my 97 GMC Sierra pick-up has had a slight hesitation when accelerating. After it runs a while, there’s no problem. In the afternoons, it doesn’t do this. It is at the shop now & of course, if didn’t do it while they had it, so they are still checking for problems. Any ideas? Thanks

---

<div class="post-metadata">

**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\
**Post date:** [September 29, 2009, 6:41pm UTC](https://community.cartalk.com/t/hesitation-in-mornings/37316/2 "2009-09-29T18:41:38Z")

</div>

I assume no check engine light?  
Has the manual recommended maintenance (filters, plugs etc.) been done? That’s where to start.

From there put a bottle of Chevron or Sea Foam in the gas tank.  
Get the ignition system checked out.  
Check the fuel pressure.  
Get a compression test.  
Get the head gaskets tested.

Hopefully it will be fixed before you reach the bottom of the list.

---

<div class="post-metadata">

**Author:** ![fitjeep](https://avatars.discourse-cdn.com/v4/letter/f/e79b87/32.png) [@fitjeep](https://community.cartalk.com/u/fitjeep)\
**Post date:** [September 29, 2009, 6:42pm UTC](https://community.cartalk.com/t/hesitation-in-mornings/37316/3 "2009-09-29T18:42:54Z")

</div>

There’s something wrong in the cold start system, like the coolant temperature sensor or the Idle Air Control. You may need to visit a dealer or other mechanic who is familiar with these trucks.

---

<div class="post-metadata">

**Author:** ![carhelp199](https://avatars.discourse-cdn.com/v4/letter/c/3be4f8/32.png) [@carhelp199](https://community.cartalk.com/u/carhelp199)\
**Post date:** [September 30, 2009, 1:16am UTC](https://community.cartalk.com/t/hesitation-in-mornings/37316/4 "2009-09-30T01:16:06Z")

</div>

Thanks, they replaced the oxygen sensor today. We’ll see in the morning if that works. It was fine on the way home.

---

<div class="post-metadata">

**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:** [September 30, 2009, 11:26am UTC](https://community.cartalk.com/t/hesitation-in-mornings/37316/5 "2009-09-30T11:26:22Z")

</div>

Has it been damp in the mornings? How old are those spark plug wires?