As the topic suggests, I've been having some issues. I went and got tuned last week pretty conservatively on E85. I made 507whp on a mustang dyno at 16.4 PSI. My tuner has me running around 12 degrees timing at 16psi. The first WOT pull he did on the dyno had some spark blow out so he adjusted the gap of my plugs down from .023 to .018(HR 8 NGK coppers)-- and the issue went away and the tune finished up fine. On the dyno he was commanding a 11.4 AFR at full boost, and low load AFR's were fine as well.

Back home a couple of days later.. I hopped in the car and took it out to make sure everything was running right with it and the AFR's in boost were down in the low 10s--- and cruising AFR's are in the 11's and 12's... The car will go above 5k but that's around the range it's at 10PSI and it starts to misfire heavily... It feels exactly like spark blow out so I'm almost sure that's it.. however.. it's at lower boost and RPMs than I was running on pump gas and I've never had these issues with such low gap before. I tried gapping the plugs down to .014 just to see if that helped at all.. Nothing-- Tried my buddies heat range 9 iridiums from his turbo RSX gapped at .023-- and the same issue occurred. I even swapped in my wife's coil packs from her CR-V to see if maybe that was the issue.

Has anyone had this happen before, and if so, what was your fix?

I'm in the process of sending logs back and forth with my tuner.. he tried to take a little fuel out of my map in boost but it didn't appear to help the issue.

The only thing I've done to the car since I got back from the tuner was install the puddy mod air pump valve cover.

Any suggestions would be great.

Info about my setup:

5858cea
sheepey manifold
1200cc Donkey Power Injectors
450lph walbro w/ SOS wiring kit
Radium fuel rail and -6AN feed line adapter
Running base pressure of around 59-60

 

Might need to have your injectors cleaned.

I had a very similar problem and that solved it got me.

E85 has a tendency to clean all the junk out of your tank/lines and since these cars don't have inline fuel filters like most cars the junk can often make its way all the way to the injectors, causing them to be partially blocked and thus not deliver enough fuel at higher levels.

 

You were running rich with dirty injectors? The only reason I ask is because I figured that would cause a lean effect.

 

Depending on how your ECU is tuned/setup it is possible. I think mine would go lean momentarily and then try and compensate by pulling timing and then go super rich.

Seemed surprising to me too but my tuner was confident that was the problem so I took his word for it and he was right.

 

I'm running on an AEM v2.. When I was at the tuner this time around he was saying that my car wasn't responding well to O2 feedback(auto adjusting to match a certain AFR) so he disabled it. But on the same note, wouldn't that mean my fuel maps wouldn't compensate for lack of fuel anymore-- even in boost?

Thanks for replying man

 

If I remember correctly there are safety options outside of O2 feedback that will still try and change fuel/ignition timing in certain situations so you don't damage your motor.

I'm not an expert though, just throwing it out there as a possibility... especially since it is a relatively quick/cheap fix or thing to check on.

No problem. Good luck getting it figured out.

 

Get a set of brand new rsx coils.

 

Check your FPR vacuum hose to see if it got disconnected when you added the air pump cover. Maybe that is causing your rich conditions under low throttle and cruising.

 

Go with the NGK BKR8EIX iridium plugs gapped to around .018". I tried switching to the copper plugs a while back on e85 and spark blowout started. Switched back to the iridiums and it went away. Could also be the coils if you have a lot of miles on them.

9's are too cold of a plug for your power btw.

 

Yeah, that's why I'm using heat range 8--- My buddies RSX makes similar power but all of his sources swear by that setup on his K-Series.. Either way, my spark blow out is happening at STUPID low boost and RPMs.. so I'm really curious if it's actually blow out caused by e85 at that level, or if it's somehow in the tune elsewhere. Thanks for you guys input though-- I appreciate it.