Hey there, i was just wondering if anybody know what can it be, i just installed a CAI (K&N typhoon, ) in my manual xb, and i never notice before so i was wondering, but know i can tell that the idle is not constant after the car is been running for a while, when i get to a stop ligh and i am in neutral, the idle varies fron 650 rpm to 900 rpm, so i did not know if this is normal in manual cars or it has to do w/ the mod, i alway had automatic cars before.
thx.

 

it's the intake..

check to make sure your MAF sensor is clean..

 

Thx, but i am kind of new in this, How do i check if the MAF sensor is clean, and if not clean how do i clean it?
Thx again.

 

if yer running your AC the idle can be a little rought too.

 

dont start up with ac on when the car is cold

 

Every now and then when I'm at a light (in neutral), my idle rises alittle and drops back to like 650. I think its normal when you have your A/C on espically. I've noticed it in my '91 Toyota pick-up, '96 and '02 Odyssey also (those cars are Auto obviously)

 

I've noticed the same thing since I installed my Typhoon intake. In my case, the check engine light also came on. I was tinkering around with it and noticed something interesting... the way that the MAF sensor mounts in the K&N intake flows air the exact opposite direction through the sensor as compared to the stock housing. I'm wondering if this is what is causing the idling problems. I also saw another post in which someone else also had their check engine light come on...

???

 

i JUST bought my new xB last night, a manual tranny model. was a demo, had 212 miles on it when i picked it up. in the 400 miles i've driven since last night i've noticed STOCK, with NO options installed, that the idle moves from 600-1000 seemingly of its own accord, with no pattern to it, and i have not turned on the AC even ONCE. we're talking bone stock xB w/ 500 miles on it and no AC on, and i'm having the same problem. WHAT GIVES.

 

Ditto. Stock xB Manual with 188 miles on it (got it w/ 5) At idle, no A/C, idle will drop to where it starts to get rough, watching tach it seems to go from about 550 to almost 1000 and then back again. :? Not all the time but enough to have me wondering what's up with this.

Any ideas here?

 

did you get the car cheeper than sticker since it was a demo? maybe the engine does that because its been driven hard for the past 212 miles and was not broken in properly.

 

As is typical with new cars, the first tank or two of gas allows the vehicle ECU to "learn" the vehicle, as well as the driving habits of the driver. Its all about the ECU seeing sensors in a "normal" operating environment.

This is done as there are several variables that are taken into account for various atmospheric conditions (ie altitude, humidity, temperature) that aren't going to be the same everywhere the car is sold. So the cars computer learns what the deal is where it is at today, forgetting about what it was where the car was designed.

The problem that I see with a new car is that someone following the new car recommended break in driving methods is going to be a lot kinder to the car, varying engine speed and braking easier than normal. So the table that the ecu looks to after learning for the 1st 300 miles or so won't necessarily be the one that the ecu should be looking at 1000 miles down the road.

There are two remedies for this that are really quite simple. The first is to do nothing. All modern ecu cars are constantly doing the learning bit, seasons being one reason. So if you wait for a couple tankfuls of gas to be driven the ecu should be pretty close to how it should be for your daily driving routine.

The second is to disconnect the negative battery cable at the battery and let it stay off for a period of time. The cars that I was accustomed to modding prior to scion took less than 30 seconds to drain the charge in the ecu capacitors, but it may be different for the scion. I would just say 30 minutes. Disconnect the battery cable, put the end in a ziplock to keep it from slipping back and regrounding, and go watch a southpark. Return and reconnect. You will be doing the "relearning" thing so drive it like you normally would. Beat it to death and if thats not your usual driving style, then the ecu won't be where you really want it. So do it right the 1st time and there won't be a repeat.

BTW my 1st post and am looking forward to seeing what we can do to these cars as a group. DSMs and most recently an IS300 were my vehicles of choice to mod.

 

i've noticed with ground wires that the idle has gotten much much smoother... it doesn't bounce at stop unless i got the a/c on.

 

A good ground kit will do wonders for this problem... Your seeing a surge in idle probly when the fan or ac kicks on/off--- if this isn't the effect try cleaning the maf sensor, and if this doesn't work just give it some time, the car is still brand new. My xB had a strange idle in the first 500 or 600 miles.. I have noticed a big difference in how it performs just through the breaking in, and its still gonna be a long time before its done- You just got a new car so your worried about every little noise, click, chirp, chip etc. Just relax and remember its a yota!

 

I just installed the K&N and now I am also getting the weird idling problem. Also my check engine, vsc, and trac off lights are on also. I tryed disconnecting the negative cable and it went away only to come back. This sucks. If this continues I'll have to put my original filter back on. Couple of times the car stalled also when I had the car in neutral and coasting. This happened after the lights came on. Gonna try the suggestion up above and leave the negative off for a half hour.

 

get the randode racing ground wire kit. I had it installed on mine, and BYE BYE rough idle. and, my system hits harder, and i get like 2mpg more than b 4!

BTW, whoever bought the car with 212 miles on it......that car is what they call a UNWIND!, its when someone buys a car, and then can't get financed for it, so they have to bring it back! i hope you got a better deal on it, cuz u just bought a USED car :?

 

make your own ground kit... mine cost me 5 bucks =P

 

Well I tryed the suggestions above and the dumb lights came on again. I don't really want to invest in a ground kit and then find out the lights problem continues. But thanks for the suggestion. Think I'm going to reinstall the old filter back and send it back. I can't stand seeing the Engine light on and the other two lights for that matter. Maybe I'll try the Injen at another time.

 

my goes from 500 to 900 rpms when i am in idle from time to time. i am keeping a close eye to see if i see any habits and if at certain times it's doing it.