using RACV on OBD1

[SquirtAndSpark]

this is something that I always have thinking, why don't use a RACV and use a external output from ECU with a "custom function" to control the RACV?

I think (maybe I'm wrong) that some ECUs we can control a output, like 0-5v regulation or PWM. in that point if the RACV works with different parameters/rages we just have to make an interface.

or we can go longer, and make a additional "ecu" that reads the ECT and alone controls the RACV.

I really like the way that an civic EP3 tune the idle speed, old thermo valves sucks!

[CRX2]

I really like the way that an civic EP3 tune the idle speed, old thermo valves sucks!

EACV = Electronic Air Control Valve , only can adjust idle , can not raise enough for "cold start" and needs a thermo valve.

IACV = Idle Air Control Valve. Regulates ALL idle, including cold start. And it does not need a thermo valve...

RACV is a weird thing... Replace it for a IACV.

Your idea off adding an extra output to the ECU is not that difficult. The software however is a bigger problem...

[SquirtAndSpark]

I was thinking that IACV and EACV are the same

so for a d16z6 IM swap, it have EACV or IACV? EACV right? since they was a FIV (fast idle valve)

for the RACV some "after-market" ecu's have a boost controller , and his output is PWM, so I think that isn't so much difficult make a interface for RACV.


very useful information, tanks

[CRX2]

IACV is being used on OBD2B cars... A B16A2 OBD2B had an IACV.

An IACV had a bigger aircapacity which it can regulate. An OBD1 ECU can regulate it pretty well when you change the dutycycle in the software.