GSLENK
10+ Year Contributor
- 1,416
- 51
- May 25, 2011
-
DC,
Maryland
I swapped to E85 5 days ago. That is about 300 miles ago. And something is up. Car was running beautifully for the first tank. Now the performance has degraded. I HIGHLY doubt it is in the tune. It was running perfect.
Between 2k rpm and 4k rpm, the AFR will go stupid lean. Typically jump to 15:1 then crawl through 16:1, then up to 18:1. As soon as ~4k rpm or any real load, then it drops closer to target around 13:1 and high rpm/load to 12:1 as usual. It isn't perfectly on target as before, but it gets close.
Any ideas?
I want to think a fuel system problem (surprised it actually is happening this early though). OR an ECU problem.
Does this sound like anything that has ever happened to anyone? What typically gets clogged badly first?
Here is the rundown on my fuel system (not completely optimized for E85 yet, but pretty close):
Walbro 255hp (regular sock, Basic install kit-jnz or ex-psi IDK)
OEM fuel feed line all the way to Fuel lab 818 fuel filter with 10 micron 3" paper filter
Teflon SS line filter to tank. (installed after E85 swap)
OEM fuel rail, STM 6an fittings both sides
1250 FIC Blue Max injectors, pretty much brand new.
Teflon SS line to Fuel lab AFPR @ 43psi base fuel pressure
GM Flex fuel sensor right off of return side
Teflon return line installed before E85 (for about 500-1000 miles)
I just pulled the filter thinking it was my nightmare. Nope. It was not that dirty. "Cleaned it" with gas and brake cleaner and comp. air. Took another log and the same crap happened.
Could the fuel pump sock be clogged this early? I am really at a loss here.
Between 2k rpm and 4k rpm, the AFR will go stupid lean. Typically jump to 15:1 then crawl through 16:1, then up to 18:1. As soon as ~4k rpm or any real load, then it drops closer to target around 13:1 and high rpm/load to 12:1 as usual. It isn't perfectly on target as before, but it gets close.
Any ideas?
I want to think a fuel system problem (surprised it actually is happening this early though). OR an ECU problem.
Does this sound like anything that has ever happened to anyone? What typically gets clogged badly first?
Here is the rundown on my fuel system (not completely optimized for E85 yet, but pretty close):
Walbro 255hp (regular sock, Basic install kit-jnz or ex-psi IDK)
OEM fuel feed line all the way to Fuel lab 818 fuel filter with 10 micron 3" paper filter
Teflon SS line filter to tank. (installed after E85 swap)
OEM fuel rail, STM 6an fittings both sides
1250 FIC Blue Max injectors, pretty much brand new.
Teflon SS line to Fuel lab AFPR @ 43psi base fuel pressure
GM Flex fuel sensor right off of return side
Teflon return line installed before E85 (for about 500-1000 miles)
I just pulled the filter thinking it was my nightmare. Nope. It was not that dirty. "Cleaned it" with gas and brake cleaner and comp. air. Took another log and the same crap happened.
Could the fuel pump sock be clogged this early? I am really at a loss here.