arychel

I have been battling with a wierd idle lately. It goes down low and almost to a stall sometimes while at a stop (mainly in drive and reverse) and sometimes it will recover to normal, other times it won't until you give it gas. I have replaced an O2 sensor, had the IAC cleaned, fuel infectors cleaned, and even replaced a battery cable (which was too loose causing a sometimes no start).

What usually happens with all these tries to fix the problem is that at first, for a few hours of driving the car behaves perfectly, then it goes back to its old tricks.

Each of these repairs involved resetting of the ECU. Could it be that the car is ok at first when the ecu is reset, but there is something wrong with the ecu that eventually returns once it is up and running for awhile?

By the way, my mechanic can't figure out what is wrong: they have tested everything under the sun. Oh, yeah, it is setting no codes now (it used to set an O2 sensor code before I replaced it).

Please help me... this has been driving me crazy for more than 6 months...

Slacker87

Mine has been doing the same thing 1990 crx si d16a6. I tightened the idle screw and it stopped for awhile but everyonce in awhile it does the same thing. Checked injectors, spark plugs, distributer, idle air control valve, fast idle thermo valve, cleaned throttle body. No vaccume leaks. The only thing i havn't checked was the fuel filter... i dont know where it is. Let me know if you ever figure it out. Mine has an exaust and im sick of people thinking im reving up at them. How do you reset the ecu? im pretty new to honda's i've only had mine a month

arychel

You reset the ecu 2 ways: disconnecting the negative battery cable or putting the hazard fuse in the fusebox under the hood.

If I can get my hands on another computer, I will try swapping them to see if it helps.

I have a relatively new fuel filter, so I don't think that is it.

arychel

I think I have finally figured it out... just a little bit more diagnosing and I will know for sure.

The reason my car never idled low while at a stop is because the mechanic never drove it in the dark, in the rain, while it is cold. When I have the wipers, headlights, heater, and radio on all at the same time (which is most of the time when I drive) it is much more likely for the problem to happen. This I think points to the IAC motor being to blame even though it has been cleaned: it must be occasionally acting up and not maintaining a good idle when I have a lot of things on.

f150harleytruck7

i am having the same problem, the car sometimes drops to like 500 rpms or barley above the 500 mark and kinda stumbles at times too, it also seems to have less power when idling low at an idle and the exhaust seems to be louder when doing this also, but mine does it with just the radio on, never tried without it on but im sure it would do the same thing
so you think its still the iacv acting up, i have no codes either after replacing the o2 sensor

KrenzyRyan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by f150harleytruck7 &raquo;</TD></TR><TR><TD CLASS="quote">i am having the same problem, the car sometimes drops to like 500 rpms or barley above the 500 mark and kinda stumbles at times too, it also seems to have less power when idling low at an idle and the exhaust seems to be louder when doing this also, but mine does it with just the radio on, never tried without it on but im sure it would do the same thing
so you think its still the iacv acting up, i have no codes either after replacing the o2 sensor</TD></TR></TABLE>

Yeah, same here, mine usually drops to 500 rpm, then goes up to 1200 rpm. And this is all after I installed a 2000 watt sound system. Any suggestions? Bigger battery?

92 si hatch

make sure your throttle cable is taught. You may have some play at the throttlebody. You will have two nuts, one on either side of the bracket. If one of the nuts are loose then this could cause funky idles

rckstar

Have the throttle body checked by a trusted mechanic.