Still running rich :: rough idle

[90SRpwrd240]

Ok so I drove my car up to Boston last weekend, and ever since, I've had a semi-rough idle, and I'm running really rich. Today I changed my plugs and used NGK BKR7EIX iridiums. Also I changed my fuel filter to the z32 300zx. Still I have a rough idle, and shes breaking up a little bit, but not too bad. What should be my next step?? I'm thinking O2 sensor could be shot, but I'd like the advice from the pro's haha...Yes, I did search, but nobody posted results after changing said parts. Car is 1990 240sx with redtop SR20DET, Walbro 255lph, FMIC, turbo back 3" exhaust with cat-delete. Any help is appreciated, Thanks!

[90SRpwrd240]

nobody?!

[S13FASTBACKSR]

does it misfire/hesitate/bog when accelerating? test your tps, clean your maf and try pulling codes off of your ecu

[90SRpwrd240]

No, it doesnt bog during accellerating but it will occationally misfire, but not bad. When I let go of the gas to shift, it will sometimes misfire a little bit and also an occational backfire which is usually normal because the blowoff is not recirced. When I put the clutch in to stop at a light, the idle goes down really low to almost 0rpm then jumps back up to about 800rpm for idle. It has only stalled once.

[S13FASTBACKSR]

the problem might lie in the bov. non-recirculated valves cause the car to run rich and sometimes have bad idle as well as cause the idle to drop very low when letting off the acclerator. I know yours was fine before the trip but its possible the spring loosened up a bit..try tightening it

[90SRpwrd240]

Will do, thanks for the help, I'll keep you posted.

[playastarkz123]

i dont mean to thread jack, but i have this same problem on my redtop sr. I too also have a BOV that cannot be recir. However my problem isnt only at idle. Some times if im not in boost (just accelerating normally) the car accelerates funny. the best way i can describe it is that is sounds like i have WRX. lol. i also have a z32 maf and my safc set HW 2in 6out.

idk if anyone knows what could be the problem here

[90SRpwrd240]

So I tightened up the BOV and she's running like a champ again! Thanks for the help S13FASTBACKSR.

As for your problem, playastarkz123, the same thing happened to my Talon when I had it. I couldn't figure it out (the broken up accelleration) so I took it to the shop for diagnostics. It turned out to be a bad TPS. I'm sure it could be many more things but I just thought I would give my .02

[S13FASTBACKSR]

yay i solved the problem!!! lol your welcome..playa are you running rich?

[redtop91]

Hmmmm. Might be my problem too...

[playastarkz123]

As for your problem, playastarkz123, the same thing happened to my Talon when I had it. I couldn't figure it out (the broken up accelleration) so I took it to the shop for diagnostics. It turned out to be a bad TPS. I'm sure it could be many more things but I just thought I would give my .02

I was thinkin along those lines also. Tomarrow im going to try cleaning out the throttle body and see how that works. After ill check a few other things like the spark plugs and such. Hopefully a little cleaning is all it takes

[Deadrodent]

i have the same problem too..when i come to a stop my idle dips down and then jumps back up and occasionally stalls..i have disconnected the hks bov and it does the same exact thing so i'm pretty sure it's not my bov. vaccuum reads 16-17 at idle when it used to be 18-19...is it my AAC valve or a vac leak?