Rich, lean, rich, lean....

[krutten]

Whats up everyone, I'm new to the forum and am new to Hondas. I took advanced/vocational auto in high school for 2 years and did oil changes for about 3 months and thats the extent of my car knowledge so...fairly limited.
Just bought a 1990 Crx w/ a b16a3 and it had an SAFC in it so I swapped with a buddy of mine for a VAFC to control the v-tech points. After doing the swap my car has had some inconsistencies with its fuel mixture it likes to go from being consistent and just where I want it to be to all of the sudden being all over the indicator even when I'm just holding the throttle at like 30% and rich, so much so that I can smell it. So I'll lean it out on the vafc and that help the richness somewhat, but its still all over the indicator and I can still smell it (not as much).

I'm thinking it might be a sensor problem? Possibly an O2 sensor? I tried searching to find other threads on this topic...no luck. Any input would be appreciated, let me know if any more info is needed. Thanks

 

[formby]

um...if you dont have mods like cams and a real CR take the vafc off....and get the ecu chipped and dyno tuned....it looks cool and it works but 1. you dont need it
2. a reals ems is 100x better
3. it might be fucked up


i wish i could help you more, but this is all i got

 

[MikeBergy]

If the VAFC is looking at the narrowband output from the stock o2 sensor, it doesn't know any more accurate afr info than you do by sticking your nose in the tailpipe. The narrow band signal is junk for anything except for trimming of the fuel by the ecu. Get a wideband and real engine management as previously stated. You could sell that vafc, and get most of the stuff necessary for a good diy ems.

 

[krutten]

So, for now would I be better off taking out the vafc and just running the stock ecu by itself? Should I just give that a whirl and see if it improves? I was planning on a real ems eventually anyways, just wasnt top of the list. Also, I sort of have a hard time blaming the prob on the vafc because it did it once with the safc too, and then didnt really start doing it a lot until like 2 weeks after i put in the vafc.

Thanks for the input -- later