Discussion in 'Engine' started by ALEX-CY, Nov 7, 2016.
Possibly the IACV.
I already replace it with genuine new one
Ah, that theory is blown out of the water then. Possible vac leak??
About the RPM's going from 2,100-1,900---My RPM's slightly change as well when my car is running in 'closed loop' and up to (or near) operating temp. I narrowed it down to the primary O2 sensor. With a scan tool, I noted the RPM's go up a little when the O2 senor is reading rich, and goes down a little when its reading lean. This is with a new O2 sensor from Honda. If its easy enough for you, you can always unplug the primary O2 sensor, try to duplicate the issue, and compare results. I now call this rhythm 'her heart beat' haha.
Had a thought about the A/C low idle issue-- I wonder if your ECU is expecting your engine to have a 'Fast Idle Valve' and thus your idle is lower than it should be. DC2 R's never had the Fast Idle Valve here in America, but we also never saw them until 1997-2001. We always seem to get the short end of the stick. Another example is the older 'GSR' (94-97) came equipped with the Fast Idle Valve, but the 98-01 GSR's didn't- and the ECU was programed for this change.
if you mean vacuum leak I already check this
my car has jdm itr b18cr engine and ecu, so only one o2 sensor and not fast idle valve/ just ab idle valve which is genuine new
Sounds like every thing should be talking to each other properly and 'as designed' then. Does anyone know what octane rating they have in Japan? I heard it was close to 100? Perhaps the ignition curves in the JDM ECU are 'off their mark' for the lower rated octane gas in your area?
I only use 98 octane. so don't think this is the problem
now is summer. still have the problem
Swap ecu with known good one
I already do this
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