Evo 8 stutters and goes lean above 20 psi.All of a sudden.
#1
Evolved Member
Thread Starter
Evo 8 stutters and goes lean above 20 psi.All of a sudden.
Whats up guys. So all of a sudden my car started acting up on WOT.
Fp red
E85
All supporting mods.
Car went from running great to now when i do wot pulls as soon as i hit 20 psi or so you feel either a studder or misfire. And wideband spikes lean.
Any thoughts? Do the evo 8s have fuel pressure relay issue like x?
If it was a lack of fuel pressure lets say. I dont think it would stutter.
Any thoughts?
Fp red
E85
All supporting mods.
Car went from running great to now when i do wot pulls as soon as i hit 20 psi or so you feel either a studder or misfire. And wideband spikes lean.
Any thoughts? Do the evo 8s have fuel pressure relay issue like x?
If it was a lack of fuel pressure lets say. I dont think it would stutter.
Any thoughts?
#3
Evolved Member
Thread Starter
Yes did a log this morning. I don't see anything that catches my attention in the log.
It all started with my check engine light coming on. For fuel trim code. I had -11.9 fuel trim so I adjusted accordingly. Trims are with in 5 % now and chek engine lamp off.
Still didn't fix issue.
Im beginning to think this is a outside influence such as coils or wires.
I swapped out my plugs also. They weren't brand new but good known units.
I just don't understand if its a misfire or a fuel cut or boost cut.
It all started with my check engine light coming on. For fuel trim code. I had -11.9 fuel trim so I adjusted accordingly. Trims are with in 5 % now and chek engine lamp off.
Still didn't fix issue.
Im beginning to think this is a outside influence such as coils or wires.
I swapped out my plugs also. They weren't brand new but good known units.
I just don't understand if its a misfire or a fuel cut or boost cut.
#4
Evolved Member
Thread Starter
NOTES:
This vehicle is on speed density Running a OMNI 4 bar and running on fuel temp.
Omni has been replaced with good known unit.
Exhaust cam position sensor has been swapped with good known unit.
This vehicle is on speed density Running a OMNI 4 bar and running on fuel temp.
Omni has been replaced with good known unit.
Exhaust cam position sensor has been swapped with good known unit.
#6
Evolved Member
Thread Starter
Trending Topics
#8
Evolved Member
Thread Starter
Coil ohm testing
Short SPARK CABLE- 2.794 kOHM
Long SPARK CABLE- 5.66 kOHM
Coil Boot 1.7 OHM
Coil Boot 2 1.0 OHM
Coil 1 10.3 kOHM
Coil 2 9.86 kOHM
Short SPARK CABLE- 2.794 kOHM
Long SPARK CABLE- 5.66 kOHM
Coil Boot 1.7 OHM
Coil Boot 2 1.0 OHM
Coil 1 10.3 kOHM
Coil 2 9.86 kOHM
Last edited by 4b11slayer; Jan 20, 2018 at 09:53 AM.
#10
Evolved Member
Thread Starter
Thanks.
Any other thoughts razorlab?
How can I identify boost or fuel cut? Through a log? Would I see injector duty suddenly get cut? Cause my IDC seems normal.
Also If it is boost cut I would see WGDC get cut?
#11
Evolved Member
Thread Starter
I just want be clear that this just happened from 1 day to the next.
Went out for a cruise with the boys and felt it on a wot pull. Hour later mil set for fuel trims. Adjusted fuel latency accordingly and fixed the trims. Problem still there. Maybe coincidence.
What other sensors might cause this?
Went out for a cruise with the boys and felt it on a wot pull. Hour later mil set for fuel trims. Adjusted fuel latency accordingly and fixed the trims. Problem still there. Maybe coincidence.
What other sensors might cause this?
#12
Evolved Member
Thread Starter
UPDATE: Checked fuel pump assembly for proper pump fitment and also inspected pick up screen. Dirty but not clogged. Cleaned with brake cleaner and air.
Any other thoughts? Im going to Close the spark plug gap down to .020 see if it helps.
Currently running 0.21-0.22
Any other thoughts? Im going to Close the spark plug gap down to .020 see if it helps.
Currently running 0.21-0.22
#14
EvoM Community Team Leader
Is this 91 or e85? If your trims are pulling fuel like you said that would make me think blend change on e85. -11 is pulling alot of fuel, where you able to verify if the ecu was hitting stoich when it was pulling that much fuel? If you change your scaling back to the way it was before compensating for the trims, clear them out by pulling the battery and then testing, does the problem persist?
#15
Evolved Member
Thread Starter
Yes e85 here in socal.
So just did a pull in 2nd the break up is less violent now with the plug gap set to 0.19. So maybe my coils are tired?
So just did a pull in 2nd the break up is less violent now with the plug gap set to 0.19. So maybe my coils are tired?