Do anyone of you guys have a problem with off the line hesitation? My 350 has Fujita intake & Tanabe exhaust w/Eibach Pro Kit installed. I am definitely feel the lost of power lower end but over 3K RPM, the car has some serious grunt. Is this normal? TIA.

 

try resetting the battery so that the ECU can relearn your mods. It might help.

 

Thanks for the help.

 

pretty simple you can reset ecu help until ecu relearn's.but you should lose low end torque with air mod's and exhaust.but like you said after the rpm's get up there you gain some ponies.

 

i have Injen short ram intake and have the same feeling on my car i also have the lexus HKS exhaust as well, and your right, off the line is a little sluggish ....i dyno it when i first got it and then after the mods and i gained 17 rwhp so there was hp gains.......

 

Two things I can think of:
1. since you're not getting a lot of movement of air at rest, the intake is sucking in the hot air from the engine bay. Don't know if this alone is enough to make a noticeable difference though.
2. your MAF (mass air flow sensor) could be fouled with excess oil from the filter element. This can definitely affect performance.

 

I think i've read somewhere that if the aftermarket intake tube is wider in diameter than the stock tube that the airflow is slower or something and that effects throttle response.

 

Does it do this while the engine is still cold, or after it is fully warmed up? I've noticed that my power delivery isn't very smooth until it has warmed up.

 

Switch to manual mode....

 

Does this resetting of the battery apply also to just an aftermarket exhaust on the IS minus the intake? I have had many aftermarket exhausts on other cars including full systems including intake, headers high flow cats and all the way back to the tips and have never had a problem except maybe a bit of time for the computer to recalibrate. I have a Tanabe ordered and just curious.

 

Why?

 

There is no need to reset the ECM if you are willing to let the automatic learning take place on its own. Some believe resetting the ECM manually by pulling the fuses (or disconnecting the battery and losing EVERYTHING from radio presets to nav locations) forces the ECM to learn faster. That has not been my experience with Toyota ECMs. Once the engine coolant is up to temperature, the ECM goes into closed loop and starts adjusting short term fuel trim (+/-10%) using the WB O2 sensor in the header. If short term trim exceeds +/-10% consistently, it will adjust long term fuel trim (+/-20%) to compensate for what it perceives as a permanent condition. The ST and LT trim values are also used as correction values for the open loop (throttle position over 74%) maps because these trim values are assumed to be necessary to keep the engine running in the desired A/F range.