My 05 xb had about 2900 miles on it and I've noticed now that its colder that the idle seems awful high when I start it for a couple minutes and then it seems to bounce around its never consistant. I do have a short ram intake and tanabe exhaust. Let me know what you think just want to get it taken care of if its not normal..

 

What RPM is it running at when you first start it? I have noticed mine will run as high as 1000rpms when it's really cold. As far as it bouncing around is concerned though you may want to check that your intake is connected securely and that the filter isn't getting wet; if it is loose or wet that could explain why your idle speed is bouncing around so much.

I recently drove to Arizona and back and I had a new cold air filter put on by the dealership in Albuquerque, NM. It was a huge hassle because they put the filter on without oiling it (which at the time I didn't know you had to do) and then they washed my car as a courtesy. Well, 10 mins down the road and my car starts to chug really bad. I pulled over and my intake filter was sopping wet and the hose had come almost all the way off. So, I'm speaking from experience.

 

mine does it sometimes. kinda stumbles around searching for idle.

 

No I started mine in the driveway today and it was at like 1800 rpms for like 2 mins then it went down to normal it was about 40 degrees out.

 

well whenever it's cold or hasnt been started in awhile all cars have a high idle. my xB does it and the coldest it gets out here is like 45 or 50. so far

 

yeah my tC does it as well, its normal.

 

This is normal. It will settle down --a little bit-- if you install a ground wire kit.

I believe this effect comes from the computer. You will also notice that the computer will also assist in acceleration and deceleration. If you have a Manual Tranny you will see it is more evident than in an Auto.

Dont worry about it, its just a way that Toyota/Scion can get a little more response out of such a unique power plant.

 

Thanks guys I feel much better now that I'm not the only one with this issue but if its normal then so be it. anyone else excited about the first snow I can't wait to see how my baby handles the snow! I'm all set for winter with my bun warmers on the front seats and my Yakima rack is on its ways so I can hit the moutains.. We should have a scionlife ski session anyone from pa wanna try it? if so PM me we can work something out!

Thanks again guys
Phil

 

Um, I hate to be the one to point this out but, what do you have the heater control set on when you are warming your car up?

If you have the heater set on either of the defrost settings you might not know this but you have the AC on(Defrost or Heat and Defrost). The AC goes on in these two settings so that the inside windows defog faster because they have dry air being passed over them. Try warming the car up with the heater set on a non defrost setting, or even with the fan turned off you might notice that the idel is a little more even because the AC compressor isn't cycling on and off.

I was kind of supprised that Toyota did the AC in Defog on the Scion because most cars with an AC button don't work that way, I guess Toyota figured that if they didn't build the cars that way most people wouldn't figure out that the windows defog faster with the AC on.

I bet you were wondering why the car wasn't geting warm inside when you were warming it up with the defog on weren't you.

YAKIMA Racks are for Kayaks, and bikes! My snow shoes should fit nicely inside the car with me thank you. Skis? I don't think so.

 

Umm, I warm my car up on the defog setting all the time, with the **** turned all the way to high heat. Car warms up fine, and the frost melts much quicker.

 

Even with a grounding kit the bouncy idle problem is ridiculous. I have nothing on.. no radio,a/c,heaters,defoggers NOTHING ON. Yet after driving awhile the car will automatically dip low into the rpms enough to cause the car to shake and feel like it's going to die. Try using the window switches to roll up your windows when they are already up at idle and you'll know exactly what I mean. The car litterally shudders. If theres one thing that ____es me off about these cars.... this would be it

 

I'm in AZ and mine does it regularly. Your sitting at a light and the idle just stumbles.
I remember reading a post where a guy switched to some HP aftermarket plugs and it fixed the problem.
Regardless, they all do it..............

 

have you guys went to the dealer or tightened the slack out of your throttle cables? I heard this is the common problem with the shaky idle.

 

I've tried both methods mentioned above. The sparkplugs while it takes the problem away for maybe a week it comes back. The throttle cable adjustment works for maybe 2 days before the ecu automatically adjusts it back down to low stumbly rpms at idle again. I even had it so high that it was idling at 2000rpm. The computer brought the rpms back down and because my throttlecable was so far out of adjustment the check engine light came on.

 

once I get access to the factory manuals this should be an easy fix, the ECU will adjust, but not if done properly...for example, on my honda, you have to unplug one of the idle control sensors, adjust the throttle body idle screw, etc, a few steps...there is a "right" way to bump up the base idle and not have the ECU correct it.

 

On an auto xB, how high would you be able to go on the idle speed to get rid of the stumble but not be too high while idling in gear at a stop? Or cause a problem while trying to brake or slow down.

 

Rough idle on cold start is normal, the air to fuel mixture is different and it also adjusts the idle in order to warm the engine up properly. as far as the inconsistant idle jumping, how much of a range are we talking? if it is drastically rising and falling (more than a couple hundred RPM up and down) it is most likely related to either an idle control valve, air obstruction to intake, or improper valve timing. Throttle body misalignment is sometimes the case with other vehicles and can require a computer reset. Have you had to have the battery disconnected recently? Rough idle is a common side-effect of disconnecting the ECU power on many vehicles.

 

haven't had any idle dipping problems, but when you start a cold engien it's normal for the rpm's to be a little high for a while and then dip back to normal. My ford explorer did it, and my s10 also did it but less noticible. The computer has the idle higher for initial warm up for a little while. Now it's best to warm up for 30sec-1min and then drive lightly to warm up but the initial high rpm is just to get the oil and coolant warm enough for you to drive.
In both my '88 mustang and my '91 explorer the manual said that the rpm's would be high when you first start and then if you lightly blip the throttle after 30 seconds it would go back to normal. IDK if scion's work similar but I definetly wouldn't worry about high rpms when starting in cold weather.

I am clueless on other idle issues though. Good luck.

 

Again, I am in Arizona (trust me, it's not cold!) and it does it regularly......
Sounds like it is just one of those quirks that Scion will need to fix in the future. Give me 20 more horses and I'll put up with the rough idle!!
HA!

 

Mine does the same thing. I brought it to the dealer for it, and they told me there's nothing I can do about it and that it's normal. I was also told by fellow Scionlife folk that a ground wire kit would help.