#   Hesitation and high Idle after cold start

**URL:** <https://community.cartalk.com/t/hesitation-and-high-idle-after-cold-start/143422>\
**Category:** Maintenance/Repairs\
**Created:** [July 1, 2019, 3:31pm UTC](https://community.cartalk.com/t/hesitation-and-high-idle-after-cold-start/143422 "2019-07-01T15:31:13Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![sanchez.jayson1998\_154038](https://avatars.discourse-cdn.com/v4/letter/s/3d9bf3/32.png) [@sanchez.jayson1998\_154038](https://community.cartalk.com/u/sanchez.jayson1998_154038)\
**Post date:** [July 1, 2019, 3:31pm UTC](https://community.cartalk.com/t/hesitation-and-high-idle-after-cold-start/143422/1 "2019-07-01T15:31:14Z")

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Hi there, My car is a 1997 Toyota Camry LE V6  
156,000 miles - hesitates when I am in traffic.  
For example, in stop and go traffic I will come  
to a stop slowly, and try to accelerate but  
there is about a 1 second delay when I press  
the pedal and the car goes. This doesn’t  
usually occur at high speeds just low speeds.

More important issue:

Should also mention that when I turn on the  
car on a cold start (it’s 80\*F outside), it idles  
at about 1,800 rpms. It doesn’t settle lower  
than 1k rpms until I put it in gear or wait a  
long time (5min maybe?) If I don’t wait for the  
car to settle to 1k rpm, and I choose to put it  
in drive, the idle drops from 1,800 to about 800rpm (normal I think?) And the car will “walk”  
at about 5mph which seems and feels rather  
fast because I am not pressing the gas, and  
as soon as I do it will shift into 2nd gear  
because it’s already traveling fast.

I has trouble shifting gears after cold start but not when the engine is warm.

It also is difficult to stop with brakes after cold start (because its “walking” fast)

Car runs fine and shifts good when warm after ive restarted the car (Ex. Going into a McDonalds and starting up car after 5 min away).

Car has no CEL codes  
Car passes emission test with my OBDII  
scanner(Blue Driver)

Recent Maintenance done:  
New Battery

Replaced Spark Plugs and rear  
wire set. (NGK)  
New Air Filter  
New Fuel Filter  
Changed Transmission Filter (not flushed just  
drained because ATF was black)  
New Engine Coolant Temperature Sensor  
Tried to clean IAC with throttle cleaner through bypass port.  
Cleaned MAF Sensor with MAF Sensor  
cleaner.

Could this be a bad Throttle Position Sensor, Idle Air Control Valve, or Oxygen Sensor?  
Any help would be appreciated as I am a  
college student and don’t have much money  
to throw into parts.

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**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:** [July 1, 2019, 8:10pm UTC](https://community.cartalk.com/t/hesitation-and-high-idle-after-cold-start/143422/2 "2019-07-01T20:10:44Z")

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The problem might be with a bad Idle Air Control valve.

A bad IAC valve won’t set a DTC.

The IAC valve controls the engine idle speed under all conditions.

It’s not the O2 sensor because the O2 sensor doesn’t come into play until the engine has nearly warmed up. And a bad TPS would eventually cause a Check Engine light.

Tester

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<div class="post-metadata">

**Author:** ![sanchez.jayson1998\_154038](https://avatars.discourse-cdn.com/v4/letter/s/3d9bf3/32.png) [@sanchez.jayson1998\_154038](https://community.cartalk.com/u/sanchez.jayson1998_154038)\
**Post date:** [August 13, 2019, 7:38pm UTC](https://community.cartalk.com/t/hesitation-and-high-idle-after-cold-start/143422/3 "2019-08-13T19:38:54Z")

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Hi Tester

I had the issue with a dirty IAC. I went ahead and replaced it (autozone) just to rule it out and no change has happened. I confirmed with a local mechanic that the IAC was working properly.

I am more concerned about the high idle, fast creep as if the car is “trying to get away from me,” and the higher fuel consumption at start up.

I am thinking vacuum leaks in either the brake booster, intake manifold, or O-rings on injectors?

Anyone have any other ideas?
