Fuel in the catch can

[Mspir3d]

I built the bottom end of the s54 in my car last year and replaced all the seals as well as the valve stem seals in the head. Now I get a good amount of fuel in the catch can. I know it’s e85 as it looks, smells and lights on fire like e85. Is there a seal that could be leaking fuel from the injectors into the crankcase when it’s under pressure? This one has me stumped for now.

[eacmen]

I would do an oil analysis to see if you’re getting blow-by fuel in the oil.

Are you running a wide band? Are you running rich? Im not an expert but I know target AFRs are different for E85.

[Mspir3d]

That’s a good idea, I’ll save some oil for analysis. I’m running a wide band. Since the rebuild it’s been running really rich at idle and leaner than it should under boost. I’ve been seeing the afr dip down to 10s at idle. I may try burning some next to a control sample to confirm it’s e85.

[eacmen]

That’s a good idea, I’ll save some oil for analysis. I’m running a wide band. Since the rebuild it’s been running really rich at idle and leaner than it should under boost. I’ve been seeing the afr dip down to 10s at idle.

Yeah i would get the tune dialed in
first. I bet most of the fuel in the can is just from running rich. Assuming you had good compression after the bottom end build.

[Mspir3d]

Compression was good when I checked, consistent across all cylinders..the tune is supposed to self adjust based on the o2 sensor (new), air temp sensor and the maf. I may need to go to a stand-alone in the future though.

[eacmen]

Compression was good when I checked, consistent across all cylinders..the tune is supposed to self adjust based on the o2 sensor (new) and the maf. I may need to go to a stand-alone in the future though.

I'd recommend reaching out to Hassan at HTE to see if he has had experience tuning your e85 kit.