owning a mazda B4000 pkup with 110,000 well maintained miles, I have incurred a idle problem. The AC has had Freon added, the Orphis tube cleaned, a new idle adjustment valve installed and now, diagnosed, vacuum leaks repaired and a new vacuum modulator installed.
With AC on, idle is 11 to 1200 RPM, with it off, about 625, where it should be. A racing engine is not fun at stops. any suggestions?
It really isn’t too far off the specs. Is this an automatic transmission or a manual?
If the IAC and the vacuum leaks are fixed, then it’s the ECM driving the IAC. Try disconnecting the battery for 5 minutes and the the ECM will be reset. There is a TSB for high idle, but it was not the exact same problem and its fix was vacuum leaks.