Lack of throttle responsiveness after header install - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

hpanju · 01-01-2020, 03:55 PM

Hi guys
I installed an FT86SF UEL Catted header yesterday and found that the throttle feels less responsive at low speeds. Trying to get the engine up to speed in order to get my car moving takes a lot more input than before. We had found a leak from my Perrin 2.5inch midpipe to the frontpipe but fixed it. Any suggestions as to why there’s a lack of responsiveness?

DarkPira7e · 01-01-2020, 04:13 PM

Did you get a tune to go with that install?

hpanju · 01-01-2020, 04:24 PM

Quote:

Originally Posted by DarkPira7e

Did you get a tune to go with that install?

No I have not, planning on it soon, I’ll need a custom tune though as I have a CAI

DarkPira7e · 01-01-2020, 04:36 PM

Quote:

Originally Posted by hpanju

No I have not, planning on it soon, I’ll need a custom tune though as I have a CAI

Likely the tune is exactly why the car doesn't feel right. Let us know once you get a tune.
Are you also saying you have a cold air intake on the car as well with no tune? Or is it tuned for the CAI?

86MLR · 01-01-2020, 06:14 PM

I've swapped a heap of headers and never needed a tune, I would check your wiring.

Dirty or damaged O2 sensor?

Was it running fine before the header but after the CAI?

hpanju · 01-01-2020, 06:33 PM

Quote:

Originally Posted by DarkPira7e

Likely the tune is exactly why the car doesn't feel right. Let us know once you get a tune.
Are you also saying you have a cold air intake on the car as well with no tune? Or is it tuned for the CAI?

Yeah no tune with the CAI. I’m running the Grimmspeed so the MAF scalings are very similar to stock.

hpanju · 01-01-2020, 06:34 PM

Quote:

Originally Posted by 86MLR

I've swapped a heap of headers and never needed a tune, I would check your wiring.

Dirty or damaged O2 sensor?

Was it running fine before the header but after the CAI?

Actually running fine after the CAI but before the header. Went CAI first then catback then header

86MLR · 01-01-2020, 06:38 PM

Quote:

Originally Posted by hpanju

Actually running fine after the CAI but before the header. Went CAI first then catback then header

I would first check the 2 O2 sensors wiring and connectors.

Did you use anti seize on the O2 sensor thread?, maybe you got some on one or both sensors.

Has it thrown a code yet?

hpanju · 01-01-2020, 06:48 PM

Quote:

Originally Posted by 86MLR

I would first check the 2 O2 sensors wiring and connectors.

Did you use anti seize on the O2 sensor thread?, maybe you got some on one or both sensors.

Has it thrown a code yet?

Didn’t use anti seize. Cleaned off the threading when reinstalling into the new header however. Hasn’t thrown a code yet and all the wiring seems to be fine. The car runs perfectly fine and pulls well, it’s just that the throttle feels slightly less responsive than normal.

churchx · 01-01-2020, 07:03 PM

Probably during installation battery was disconnected, and thus ecu needs some time to relearn throttle pedal's travel & fuel trims. Search around/google for dead pedal fix and shiv's reset.

hpanju · 01-01-2020, 07:48 PM

Quote:

Originally Posted by churchx

Probably during installation battery was disconnected, and thus ecu needs some time to relearn throttle pedal's travel & fuel trims. Search around/google for dead pedal fix and shiv's reset.

Actually did disconnect the battery now that I think about it. Will try the dead pedal fix and let you know. Thanks for the help!

Lantanafrs2 · 01-01-2020, 11:58 PM

It takes 50 miles or so for ecu to adjust

01-01-2020, 03:55 PM	#1
hpanju Member Join Date: Oct 2019 Drives: 2016 Subaru BRZ Location: Richmond Hill, Ontario Posts: 98 Thanks: 33 Thanked 24 Times in 18 Posts Mentioned: 2 Post(s) Tagged: 0 Thread(s)	Lack of throttle responsiveness after header install Hi guys I installed an FT86SF UEL Catted header yesterday and found that the throttle feels less responsive at low speeds. Trying to get the engine up to speed in order to get my car moving takes a lot more input than before. We had found a leak from my Perrin 2.5inch midpipe to the frontpipe but fixed it. Any suggestions as to why there’s a lack of responsiveness?

01-01-2020, 06:14 PM	#5
86MLR Senior Member Join Date: Aug 2018 Drives: 2002 VX Commodore SS LS1 Auto Location: Sydney Posts: 2,203 Thanks: 500 Thanked 2,185 Times in 1,111 Posts Mentioned: 13 Post(s) Tagged: 0 Thread(s)	I've swapped a heap of headers and never needed a tune, I would check your wiring. Dirty or damaged O2 sensor? Was it running fine before the header but after the CAI? __________________ Disclaimer: This post represents the official views of the voices in my head at the time of posting. http://www.ft86club.com/forums/showthread.php?t=133311 I'm only here for the biscuits

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01-01-2020, 04:13 PM	#2
DarkPira7e Rust bucket enthusiast Join Date: Feb 2017 Drives: 2013 Turbo Firestorm FRS Location: Vermont Posts: 4,052 Thanks: 3,307 Thanked 4,202 Times in 2,111 Posts Mentioned: 33 Post(s) Tagged: 0 Thread(s)	Did you get a tune to go with that install?

01-01-2020, 07:03 PM	#10
churchx Senior Member Join Date: Mar 2015 Drives: 2014 GT86 Location: Latvia, Riga Posts: 4,334 Thanks: 698 Thanked 2,086 Times in 1,436 Posts Mentioned: 53 Post(s) Tagged: 1 Thread(s)	Probably during installation battery was disconnected, and thus ecu needs some time to relearn throttle pedal's travel & fuel trims. Search around/google for dead pedal fix and shiv's reset.

01-01-2020, 11:58 PM	#12
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