ZC running like crap ; gas

[Digitalcivic]

Hey, my zc was running pretty good the last couple of days after having replaced my o2 sensor a couple of days ago. Well I've been pumping 89 gas since I've put the engine in, but was short on cash last night, so I filled it up with 87 ..

As soon as my car warms up the idle starts dropping and rising. I dont have a tach yet so i don't exactly know whats up, but I can hear the RPMS drop really low and then back to normal.

Is this just the gas thats causing this or is something else wrong. If its the gas should I just run it till its almost empty and continue using 89 again, or should I get some octance booster or something.

Any help, suggestions/

thanks.
Joe

[90CRXZCSi]

i think that's what was wrong with my D16A6 when i had it in my rex(the O2 sensor). I didnt even bother with and i swapped in a ZC. As for the gas, honda recommends 86 or higher. here in CO, we have 85,87 and 91. If i dont have enough money i always put in 87, other wise i put in 91. As long as 87 isnt the lowest you have in your state then i dunno what's up.

[Marc-OS]

Yeah, throw some octane booster in now, and ride that tank out. Fill up with 89/91 next tank, and report back if the problem still occurs.

[Setanta]

Ouch... I won't run anything other than 98 octane in my SiR (I even ran it in my GL 4G). I'm looking forward to the 102 octane that is rumoured to be hitting our shores soon

Lowest we have is 92 as I recollect.

[Digitalcivic]

alright, put some octane booster in the other day. Didn't take effect right away, but the next day my car was running great. The weather was warm here (about 55)and it ran pretty good for 2 days, but now its dropped back down and its running like crap. The idle is dropping again once the car warms up.
Does anyone else's ZC run like absolute crap during cold or wet weather/

[Digitalcivic]

TTT..

OK, i ran that tank of 87 almost out and filled it half full of 89. The idle is still sounding horrible. The weather is a little better, but not nice. Does anyone else know what could be causing this?

[95cvccvx]

i drive a 95 civic vx and had the same thing happen to me. i took it too many places and i was told different things that might of cause it to go up and down (the idle). From the mods, to the gas, bad 02 even though it was new, to a blown head. Then i found this one person at the speed shop said to me he had the same problem in his vx. What he found out that the ecu tries to kick down the idle, cuz it thinks that the idle is to high and cuz the car is set at that idle it doesnt want to go back down then they fight each other causing your idle to go up and down. Try setting your idle lower and drive around town and see if that works. sometimes idle kicks up when a person put new parts in their car cuz the old part is causing it to stay at a lower idle......i might be wrong just an ideal...sorry bout long post.

[Digitalcivic]

thanks, i'll give that a try. I do think my idle sounds a little high. Just got a tach so i'll know exactly whats going on when I wire it up.