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I wouldn't consider doing anything to the throttle body unless I was using forced induction. I'm sure Lexus picked the right sized hole for a stock motor.
You're sure? What is meant by the "right" size? You can use that argument for anything. "I'm sure Lexus picked the right exhaust for a stock motor" but again, what is meant by "right"?
It all comes down to what you want to accomplish. If your goal is strictly more performance, then it is very possible that Lexus did not pick the right size hole. That is why we see a power gain by changing the stock exhaust.
Lexus picked the parts it picked to get the best performance possible while maintaining the best reliability possible while keeping the car as quiet as a Lexus should be. Many of those goals are inversely related meaning you increase one thing, and something else is effected in a negative way. Car manufacturers will err on the side of caution more often then not, especially a luxury car manufacturer with a reputation for reliability.
While I'm not saying you're wrong, you may very well be correct, my point is that just because Lexus picked it, doens't make it the best choice depending on what you're trying to accomplish.
I agree with your post, there's always room for improvement. There may be a small return but it all adds up.
One thing you may want to try is verify that the throttle blade actually opens fully when given the appropriate signal from the computer.
If the inside diameter of the TB is the same as the inside diameter of the intake pipe, then boring it out might actually impede flow a bit. Regarding the butterfly opening all the way, I think there would have to be a defect for it to not open all the way.
Another throttle body inquiry. Is there a calibration service recommended to be performed on the throttle-body at a given mileage?
Also, is there a ECU Accelerator Pedal Reset Procedure known for the 2nd Gen IS similar to Nissan / Infiniti vehicles;
ECU Accelerator Pedal Reset Procedure Note Timing is critical for this to work!
1. Turn the ignition switch to on. Dash gauges lit. Don t start the engine!
2. Wait 3 seconds.
3. Fully depress and release the accelerator pedal 5 times within 5 second.
4. Wait 7 to 10 seconds.
5. Fully depress the accelerator pedal for approximately 10 seconds. At this point the check engine light starts blinking quickly indicating Diagnostic Test Mode II (Self-diagnostic results) has started.
6. Release accelerator pedal and wait 5 to 10 seconds.
7. Fully depress the accelerator pedal for 10 seconds. At this point the check engine light should change to blinking slowly indicating “Erasing ECU Memory”.
8. Release the accelerator pedal and turn the ignition switch to off.
9. Restart the engine. The check engine light should be out. Note: If the check engine light doesn't blink as described in steps 5 & 7, then the ECU isn't reset. * If above didn't work, disconnect the battery negative and pump the brake to discharge the ECU capacitors. This method is almost foolproof as long as all ECU control parameters are within their normal ranges.
Another throttle body inquiry. Is there a calibration service recommended to be performed on the throttle-body at a given mileage?
Also, is there a ECU Accelerator Pedal Reset Procedure known for the 2nd Gen IS similar to Nissan / Infiniti vehicles;
ECU Accelerator Pedal Reset Procedure Note Timing is critical for this to work!
1. Turn the ignition switch to on. Dash gauges lit. Don t start the engine!
2. Wait 3 seconds.
3. Fully depress and release the accelerator pedal 5 times within 5 second.
4. Wait 7 to 10 seconds.
5. Fully depress the accelerator pedal for approximately 10 seconds. At this point the check engine light starts blinking quickly indicating Diagnostic Test Mode II (Self-diagnostic results) has started.
6. Release accelerator pedal and wait 5 to 10 seconds.
7. Fully depress the accelerator pedal for 10 seconds. At this point the check engine light should change to blinking slowly indicating “Erasing ECU Memory”.
8. Release the accelerator pedal and turn the ignition switch to off.
9. Restart the engine. The check engine light should be out. Note: If the check engine light doesn't blink as described in steps 5 & 7, then the ECU isn't reset. * If above didn't work, disconnect the battery negative and pump the brake to discharge the ECU capacitors. This method is almost foolproof as long as all ECU control parameters are within their normal ranges.
I got nothing. You're saying, those steps are for Nisan not Lexus?
We need the full book of Toyota Cheat Codes. Im still trying to find the reset key fob cheat as it's being stupid.
I got nothing. You're saying, those steps are for Nisan not Lexus?
We need the full book of Toyota Cheat Codes. Im still trying to find the reset key fob cheat as it's being stupid.
Yes, this the ECU Accelerator Pedal Reset Procedure is for Nissan / Infiniti vehicles, and was interred if a similar procedure exists for the 2nd Gen Lexus IS (ECU Accelerator Pedal Reset)
Understood, thank you Yamehoo.
Other than the Throttle-body relearn procedure, is there a a recommended calibration procedure / service, to be performed on the throttle-body at a given mileage?
My former Mazda 6, 3.0lt V6, 6spd auto would get stupid at times and not accelerate well and/or get a dead spot.
In park, ignition on, slowly and evenly depress the throttle to the floor, hold 1sec, release at the same rate 5X, turn ignition off. Done. I heard that was common among Ford and Chevy of TBW of the time.
Anyway, each time it drove like a different car. It was a 2006 Era (actually a Ford Duratec 24 valve, DOHC).
I don't think so. After cleaning, your idle will be a little higher, that is normal. Just drive it for a few days or a week, the engine ecu will adjust it back to normal idling range.
Yes, this the ECU Accelerator Pedal Reset Procedure is for Nissan / Infiniti vehicles, and was interred if a similar procedure exists for the 2nd Gen Lexus IS (ECU Accelerator Pedal Reset)
There is no such thing for the 2nd Gen IS. Now on the second generation GS. It still had the hybrid throttle cable with pedal sensor. For that one you only needed to adjust the TPS sensor with a scan tool. It was a pain I had to rebuild my throttle body assembly. It includes Motor, TPS, and PPS.
Follow up:
Considering performing cleaning service for the throttle body with use of CRC Throttle Body & Air intake cleaner. Would like to clean back side as well if not to difficult to access, and without removing entire throttle body from it's location. Was reviewing the following video tutorial below for reference. Would like to remove just throttle body without removing any vacuum / coolant lines (photo below shows throttle body removed with lines still connected at about 3:46 during the video). Was considering replacing the gasket (OEMpart22271-31020)as well (photo below shows equivalent Fel-Pro gasket part 61472 for reference. and OEM gasket also seen in video at about 3:46). Have reviewed the many Throttle body threads (apologies if overlooked), interested if anyone has performed the throttle body cleaning with throttle body still connected to vacuum / coolant line, to access back of throttle body for cleaning, and replaced the gasket as well (and with negative battery cable removed or not).
Elexis, the best way to clean your throttle body is to remove it from the car. It's easy enough to not worry about breaking anything. Once you have it out of the car, you can take your time to clean it however you like both front and back. I happen to have an extra throttle body and I swap them every year, after the swap, then I take time to clean the one I just removed and get it ready for the next swap. The point here is once you have the throttle body on your hand, you can clean it as spotless as you want without missing any corners or edges especially in the back. Hope it helps.