Rough idle 2003 Toyota Highlander v6

[meep]

I was leaning first towards motor mounts. Oem only for the application. Start with the ones on top.

 

[The Critic]

I was leaning first towards motor mounts. Oem only for the application. Start with the ones on top.

The one on top is a torque strut. Doesn’t dampen vibrations.

 

[thejon]

I appreciate all the suggestions! Now I know where to start. So, from the picture I posted, do you think the idle looks about right in drive?

 

[6.7 CTD]

I appreciate all the suggestions! Now I know where to start. So, from the picture I posted, do you think the idle looks about right in drive?

Is the tach pic with the air conditioner on or off? If the ac is off I don’t see an issue with that Rpm. If idle rpm’s get any lower I’d have to agree with ripcord, idle air control. I am unsure if that IAC has an adjustment screw as some of the older vehicles, that aren’t drive by wire, did. Good luck.

 

[Marcozi]

Depends if it's a fluctuating vacuum leak or not

Actually, a vacuum leak will cause fluctuating idle revs as the engine computer is trying to constantly correct for the unmetered air. BMW E46s (3 series from 1998 to 2006) were notorious for vacuum leaks.

 

[classic70]

Check compression/cyl balance test. I had bought one that previous owner fired the parts cannon at with no luck. Tested compression and found low cyl/ burnt exhaust valve

 

[JMJNet]

Check the accordion connector from air filter to Throttle valve.
That can break without any sign unless you specifically look at it.

 

[thejon]

Is the tach pic with the air conditioner on or off? If the ac is off I don’t see an issue with that Rpm. If idle rpm’s get any lower I’d have to agree with ripcord, idle air control. I am unsure if that IAC has an adjustment screw as some of the older vehicles, that aren’t drive by wire, did. Good luck.

Ac off. I'd like to know how to read it. Is the first line 500?

 

[6.7 CTD]

Ac off. I'd like to know how to read it. Is the first line 500?

0/250/750/1k I’d say it appears, based on your tach, that you’re idling around 500-550. You would have to use some sort of monitoring device, such as a scan gauge or scan tool, to determine exact rpm. Heck, it may even be around 600 as that tach is fairly generic.

 

[thejon]

0/250/750/1k I’d say it appears, based on your tach, that you’re idling around 500-550. You would have to use some sort of monitoring device, such as a scan gauge or scan tool, to determine exact rpm. Heck, it may even be around 600 as that tach is fairly generic.

Ok, thanks for the info. So, in your opinion, 500-550 warmed up and in drive with the break applied is acceptable? If I put it in park, the idle goes up a bit of course. Not sure if the idle is supposed to be measured in park or drive with the break applied.

 

[6.7 CTD]

Ok, thanks for the info. So, in your opinion, 500-550 warmed up and in drive with the break applied is acceptable? If I put it in park, the idle goes up a bit of course. Not sure if the idle is supposed to be measured in park or drive with the break applied.

Yes, based on the info you provided and without physically looking at the vehicle, this seems normal.