Idling issues

[phoenixjb]

I have a 2004 Toyota avensis 2.0L 2az-fse FWD sedan. And I’m having some idling issues. 

The car has 75’000kms 

I’ve had the car for about a year now and this issue has only just started. 

When i start the car it idles at about 1000rpm in drive and 1500 in park and the steering wheel shakes. 

This lasts about 5mins and then the car idles at 1000rpm in park and 650 in drive with no shaking. 

I have read that it is normal for a car to idle at higher revs when cold for a while, but I have never felt the shaking through the steering wheel before now. 

I have done regular oil changes, cars got a fresh air filter, spark plugs were replaced recently, and I’ve cleaned the MAS sensor and the PCV valve with no luck.

I have not cleaned the throttle body. 

The car has no other issues. 

Anyone have any ideas on what the problem could be? And any thoughts on how I might get the car to run smoother when cold? 

Any help would be much appreciated 🙂 

Edited August 24, 2019 by FROSTYBALLS
Topic title edited to reflect subject

[paul9]

Power steering and air-conditioning can drive up your idle speed, but this one may be a problem with your auto transmission or more likely just that the system is out of calibration due to something like a bad temperature sensor or the throttle body/idle air control.

[mrfixer]

Your idle speeds are about right, although when hot and moving from D to P I would expect the idle speed to gradually drop from 1000 to about 700rpm.  If the aircon is on then the idle will bounce about somewhat as the compressor kicks on and off.

If you are not getting any vibration under any other circumstances then it would indicate a slight misfire with a cold engine. That could be due to an ignition, fuelling or inlet air leakage issue (vacuum leak, inlet gasket).

As a starting point I would go on eBay and get a cheap Toyota Techstream  CD and lead. Then do some detective work looking at sensor readings on a cold start. You may find some stored trouble codes relating to misfire.

[phoenixjb]

Thanks for the fast replies guys. I’ve ordered a tech stream CD and cable so I’ll see what that shows when it arrives. 

In the mean time do you think it’s worth cleaning the IAC valve and throttle body?