Car sputtering and cutting power at WOT - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

Cal3000 · 10-18-2017, 03:16 AM

As I approach 150k miles and 130k boosted miles on my car, I'm starting to see issues. I'm not sure if I have a vac leak but when I WOT my car, power is cut and the engine doesn't want to climb in rpms at random times. It just hangs at say, 4k or 5k rpm under WOT. It happens quite a bit. It's more pronounced on pump gas than e85. I'm thinking this could be the effect of a vacuum leak somewhere. I'm not sure what else can cause this.
Any one else experience such issues?

guybo · 10-18-2017, 06:10 AM

Vacuum leaks usually happen at low RPM, not high RPM. That is not a typical vacuum leak symptom

StraightOuttaCanadaEh · 10-18-2017, 09:48 AM

Failing fuel pump? Coil pack? Spark plug? Clogged injectors?

Amputechture · 10-18-2017, 11:43 AM

Perhaps failing MAP sensor? A lot of these OMNIs are shitting out on people lately.

Sportsguy83 · 10-18-2017, 01:15 PM

What does your AFR look like when it happens, have you taken a log to see timing, engine load, boost when the issue happens? Is it particular to a single gear? etc..

rb6freak · 10-18-2017, 01:39 PM

+1 on the MAP sensor as my first thought.

Fred E · 10-18-2017, 03:49 PM

+1 for the MAP sensor as well. There have been several reports of Omni MAP sensors failing, and the symptoms fit.

guybo · 10-18-2017, 07:47 PM

Let's see LTFT and STFT at idle, 2500 RPM and WOT

Cal3000 · 10-19-2017, 12:55 AM

Thanks! I'll try to gather this info this weekend.

Irace86.2.0 · 10-19-2017, 01:34 AM

Clogged fuel filter?

Cal3000 · 11-02-2017, 03:02 AM

I've attached some data logs. I don't know if they indicate anything. Basically I give the car some throttle and right before i let off the throttle is when the engine dragging starts happening. Basically the engine sounds like it's struggling and doesn't rev higher even with throttle. Not sure if it's a misfire or what. What's interesting, it's worse the lower the ethanol level. Basically the car performs better with higher E content and performs like crap on pump gas. This issue just started happening.
If anyone sees anything wrong,
Thanks

CSG Mike · 11-02-2017, 05:28 AM

Your AFR and MAP is pretty wild, along with some fuel trims.

Replace your MAP, or test with a known MAP.

Dru670 · 12-02-2017, 04:34 AM

Interesting I'm experiencing the problem once and awhile these past about 3 months now. I have about 35k miles with less than 10k on boost (JRSC C38) on stock MAP. It's happened on 91 and e85. I can't figure it out.
This is a data log using Torque App over a month ago.
https://datazap.me/u/dru670/engine-s...17-18-19-20-21
Been meaning to do a data log with ecutek to have my tuner take a look at it.

Amputechture · 12-04-2017, 12:21 AM

Quote:

Originally Posted by Dru670

Interesting I'm experiencing the problem once and awhile these past about 3 months now. I have about 35k miles with less than 10k on boost (JRSC C38) on stock MAP. It's happened on 91 and e85. I can't figure it out.
This is a data log using Torque App over a month ago.
https://datazap.me/u/dru670/engine-s...17-18-19-20-21
Been meaning to do a data log with ecutek to have my tuner take a look at it.

Perhaps I'm misreading your post...but you are supercharged on the stock map sensor? The standard JRSC pulley makes more boost than the OEM sensor's range.

10-18-2017, 03:16 AM	#1
Cal3000 Senior Member Join Date: Dec 2012 Drives: Panda FR-S Location: Corona, California Posts: 531 Thanks: 297 Thanked 377 Times in 161 Posts Mentioned: 3 Post(s) Tagged: 0 Thread(s)	Car sputtering and cutting power at WOT As I approach 150k miles and 130k boosted miles on my car, I'm starting to see issues. I'm not sure if I have a vac leak but when I WOT my car, power is cut and the engine doesn't want to climb in rpms at random times. It just hangs at say, 4k or 5k rpm under WOT. It happens quite a bit. It's more pronounced on pump gas than e85. I'm thinking this could be the effect of a vacuum leak somewhere. I'm not sure what else can cause this. Any one else experience such issues? __________________ Vortech SC on 9psi Pulley, Invidia Catless Front Pipe, Invidia N1 Catback Exhaust 242whp/197ft-lb on Mustang Dyno (91 octane water) 284whp/223ft-lb on Mustang Dyno (E85) Delicious Tuning

10-18-2017, 11:43 AM	#4
Amputechture Senior Member Join Date: Aug 2015 Drives: 2014 BRZ Location: FL Posts: 424 Thanks: 49 Thanked 143 Times in 111 Posts Mentioned: 3 Post(s) Tagged: 0 Thread(s)	Perhaps failing MAP sensor? A lot of these OMNIs are shitting out on people lately. __________________ JDL Auto Design///Turboback///Enkei///*Tial///RSR///HRI* Tuned

10-18-2017, 01:39 PM	#6
rb6freak Senior Member Join Date: Nov 2013 Drives: 23 BRZ Location: CA Posts: 540 Thanks: 546 Thanked 688 Times in 300 Posts Mentioned: 33 Post(s) Tagged: 0 Thread(s)	+1 on the MAP sensor as my first thought. __________________ SecondGen \| FirstGen \| Instagram \| YouTube

10-19-2017, 12:55 AM	#9
Cal3000 Senior Member Join Date: Dec 2012 Drives: Panda FR-S Location: Corona, California Posts: 531 Thanks: 297 Thanked 377 Times in 161 Posts Mentioned: 3 Post(s) Tagged: 0 Thread(s)	Thanks! I'll try to gather this info this weekend. __________________ Vortech SC on 9psi Pulley, Invidia Catless Front Pipe, Invidia N1 Catback Exhaust 242whp/197ft-lb on Mustang Dyno (91 octane water) 284whp/223ft-lb on Mustang Dyno (E85) Delicious Tuning

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Help, engine sputtering problems	carproblems	Engine, Exhaust, Transmission	17	09-07-2015 12:38 AM
Engine cutting power after hard cornering...	CSG Mike	Tracking / Autocross / HPDE / Drifting	19	07-04-2015 09:40 AM
Sputtering sound from right speaker when going over bumps fast?	l0aded	Electronics \| Audio \| NAV \| Infotainment	2	06-03-2013 03:47 AM
Engine sputtering while idling with check engine light flashing, WTF	speedy racer	Scion FR-S / Toyota 86 GT86 General Forum	15	08-27-2012 07:50 AM
Engine cutting power after hard cornering... Video inside	CSG Mike	Engine, Exhaust, Transmission	4	08-21-2012 09:06 AM

10-18-2017, 06:10 AM	#2
guybo Huge E85 fan! Join Date: May 2016 Drives: 2016 Scion FRS Location: Tampa, FL, USA Posts: 1,850 Thanks: 539 Thanked 1,010 Times in 605 Posts Mentioned: 32 Post(s) Tagged: 0 Thread(s)	Vacuum leaks usually happen at low RPM, not high RPM. That is not a typical vacuum leak symptom

10-18-2017, 09:48 AM	#3
StraightOuttaCanadaEh Wes Join Date: Feb 2017 Drives: Artisan Spirits '17 86 Location: Toronto Posts: 2,868 Thanks: 1,248 Thanked 1,734 Times in 1,025 Posts Mentioned: 21 Post(s) Tagged: 0 Thread(s)	Failing fuel pump? Coil pack? Spark plug? Clogged injectors?

10-18-2017, 03:49 PM	#7
Fred E Senior Member Join Date: Dec 2013 Drives: WRB BRZ Location: New Jersey Posts: 261 Thanks: 83 Thanked 150 Times in 96 Posts Mentioned: 1 Post(s) Tagged: 0 Thread(s)	+1 for the MAP sensor as well. There have been several reports of Omni MAP sensors failing, and the symptoms fit.

10-18-2017, 07:47 PM	#8
guybo Huge E85 fan! Join Date: May 2016 Drives: 2016 Scion FRS Location: Tampa, FL, USA Posts: 1,850 Thanks: 539 Thanked 1,010 Times in 605 Posts Mentioned: 32 Post(s) Tagged: 0 Thread(s)	Let's see LTFT and STFT at idle, 2500 RPM and WOT

10-19-2017, 01:34 AM	#10
Irace86.2.0 Senior Member Join Date: Mar 2017 Drives: Q5 + BRZ + M796 Location: Santa Rosa, CA Posts: 7,884 Thanks: 5,668 Thanked 5,810 Times in 3,300 Posts Mentioned: 70 Post(s) Tagged: 0 Thread(s)	Clogged fuel filter?

11-02-2017, 05:28 AM	#12
CSG Mike Join Date: Jul 2012 Drives: S2000 CR Location: Orange County Posts: 14,561 Thanks: 8,941 Thanked 14,211 Times in 6,854 Posts Mentioned: 970 Post(s) Tagged: 14 Thread(s)	Your AFR and MAP is pretty wild, along with some fuel trims. Replace your MAP, or test with a known MAP.

12-02-2017, 04:34 AM	#13
Dru670 Senior Member Join Date: Oct 2015 Drives: 2016 Scion FR-S Location: Las Vegas Posts: 155 Thanks: 11 Thanked 8 Times in 8 Posts Mentioned: 1 Post(s) Tagged: 0 Thread(s)	Interesting I'm experiencing the problem once and awhile these past about 3 months now. I have about 35k miles with less than 10k on boost (JRSC C38) on stock MAP. It's happened on 91 and e85. I can't figure it out. This is a data log using Torque App over a month ago. https://datazap.me/u/dru670/engine-s...17-18-19-20-21 Been meaning to do a data log with ecutek to have my tuner take a look at it.

User Name		Remember Me?
Password