Jumping RMP's

[Dr Juice]

Well today i cleaned out my throttle body today and some of the top part of my intake manifold. I used carb cleaner and some brill's. I used quite a bit. Took quite a bit of effert to start it back up, had to hold throttle wide open and crank. Once it started up, there was quite a bit of black exhuast coming out, then some white, might have been just exhuast, ran fine. On my way to work was doing about 75 or so on the highway, i put the clutch in to do some coasting, and my RPMs bounce from 700 to about 1300 or so. I think i MIGHT have a bad o2 senser cuase it realy doesnt fluxuate from .25 to .75 like it should. it usualy hangs aroung .5 volts. I am also running rich, maybe due to the o2 senser. If its not an o2 senser, what could be cuasing the RPMs to bounce. BTW, when it was ideling okay, then unplugged o2 senser , was still ideling, but different. Then plugged it back in and RPMs started jumping again. No check engine light. 94 civic lx d15b7 with aftermarket intake and straight pipe with res cat back, no muffler

[Tranzlogic]

sounds like you fouled the sensor, you really shouldnt clean your intake like that anywas, it makes no snce to clean the main upper runner when all your down runners will remain dirty..if anything find a place that does BG injection flushes..now that works wonders ...also might want to adjust the throttle body a lil bit to compensate ..on the 5sfe celicas that can be a problom...pull a plug and see if they a fouling, sometimes pushing the trash thru the intake plus the residue of the cleaner can foul them out

[Dr Juice]

so lets see, i unplugged o2 seners today, still did it, took off my map senser, put 20 inch's of mecury on it to see if te resisitance fluxuated, didnt, unplugged it when it was on, car stalled out.

[tiltthe63s]

Well if u just cleaned out the intake, did u use the same gaskets of get new ones, maybe a vacum leak in one of them also carb cleaner is very harsh on that type of stuff, now about the exhuast comming back, what condition is the EGR valve that might make engines rpms bounce and also look into the PCV vlave and posably replace

[Dr Juice]

I never took it off, just took my intake off and opened the butterfly valve and sprayed carb cleaner in there and scrubbed with a brush. I think i fixed it, not sure. But all i did was let the round thing the throttle cable wrap's around, not sure of the name, but i just loosed the screw on it, so it idels lower, seems to have stoped, for the black smoke not realy sure, i dought it.

Check that, didnt fix it, but when i put the AC on high it idels like 1200 and does it much less