running rich, ways to diagnose / fix ? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

jt1583 · 04-18-2007, 10:23 PM

Never really noticed my car running rich but after daily driving it again after a few months while I was away I've been noticing a bit of fuel in my catch can. Mods include

Stock CA18DET with stock T25
Walbro 190lph fuel pump
3" turbo back
FMIC
BOV (atmosphere vent, i know i know but it wasn't rich before when I had this bov but it is now. And believe me, i'm working on getting it recirculated)

Here are my questions.
*Fuel richness seems like it could be difficult to diagnose. My first guess would be to accurately calculate the gas mileage and see just how poorly it's running. other than that it sounds like I need to throw parts at it.

The only fuel mod is the 190lph pump and I got the 190 so I wouldnt run rich but here I am. I am definetly getting a nismo fpr, will this help with leaning it out? I wasn't planning on getting an SAFC this soon but I was going to eventually, and if this can fix it I'm all for it. As for using the SAFC to fix this, I definitely wasn't planning on getting getting a wideband but how else can you tune with the SAFC other than dyno. I'm not objecting do a dyno for the tune, but seems excessive for almost stock CA. Any input on the dyno tune vs. wideband tune (not necessarily for power, but for a more realistic fuel afr).

I'm going to do a compression test to make sure my rings havent washed away and I really hope they haven't. Can you guys think of anything else to diagnose / resolve these issues? Thanks alot

slider2828 · 04-19-2007, 01:09 AM

That is crazy you get fuel in your catch can... I assume your catch can is hooked directly to your intake and maybe valve cover? Would suggest you fix it asap, as you already seem to know, it can destroy the rings....

ladiesman8527 · 04-19-2007, 07:17 AM

the open atmosphere BOV will only cause momentary richness. i'd still recirculate it tho. i'd work on getting an FPR. have u checked for codes?

04-18-2007, 10:23 PM	#1
jt1583 Zilvia Member Join Date: Jul 2005 Location: Georgia Age: 37 Posts: 264 Trader Rating: (3) Feedback Score: 3 reviews	running rich, ways to diagnose / fix ? Never really noticed my car running rich but after daily driving it again after a few months while I was away I've been noticing a bit of fuel in my catch can. Mods include Stock CA18DET with stock T25 Walbro 190lph fuel pump 3" turbo back FMIC BOV (atmosphere vent, i know i know but it wasn't rich before when I had this bov but it is now. And believe me, i'm working on getting it recirculated) Here are my questions. *Fuel richness seems like it could be difficult to diagnose. My first guess would be to accurately calculate the gas mileage and see just how poorly it's running. other than that it sounds like I need to throw parts at it. The only fuel mod is the 190lph pump and I got the 190 so I wouldnt run rich but here I am. I am definetly getting a nismo fpr, will this help with leaning it out? I wasn't planning on getting an SAFC this soon but I was going to eventually, and if this can fix it I'm all for it. As for using the SAFC to fix this, I definitely wasn't planning on getting getting a wideband but how else can you tune with the SAFC other than dyno. I'm not objecting do a dyno for the tune, but seems excessive for almost stock CA. Any input on the dyno tune vs. wideband tune (not necessarily for power, but for a more realistic fuel afr). I'm going to do a compression test to make sure my rings havent washed away and I really hope they haven't. Can you guys think of anything else to diagnose / resolve these issues? Thanks alot

04-19-2007, 01:09 AM	#2
slider2828 Post Whore! Join Date: Oct 2004 Location: San Francisco, CA Posts: 6,040 Trader Rating: (13) Feedback Score: 13 reviews	That is crazy you get fuel in your catch can... I assume your catch can is hooked directly to your intake and maybe valve cover? Would suggest you fix it asap, as you already seem to know, it can destroy the rings....

04-19-2007, 07:17 AM	#3
ladiesman8527 Zilvia Junkie Join Date: Dec 2005 Location: Collierville, TN Age: 38 Posts: 429 Trader Rating: (0) Feedback Score: 0 reviews	the open atmosphere BOV will only cause momentary richness. i'd still recirculate it tho. i'd work on getting an FPR. have u checked for codes?