1200-1900rpm high idle, still dont know what it is

[Street Lethal]

Exactly how did you check for vacuum leakage? If your experiencing a problem with the BLM, you might have yourself a defective (or soon to be) ECM. I would recommend re-checking for vacuum leaks, while getting your hands on another ECM entirely (for testing), just to be sure...

You also stated that you installed a new IAC valve, but did you measure the pintle before you installed it, or did you simply trust the factory settings...?

[torq455]

your BLM and INT are really low. but then it's not fully hot either. do you have TPS %? your idle voltage seems too high. should be around .54 . i found if you take off the TPS and, by hand, rotate the sensor simulating as if it were on the TB without opening the TB, the TPS % says 1%, then 2% and so on. when the TPS % reads 1% the idle bumps up. more throttle, more IAC steps. At .73 volts, i'm about at 4-5% tps. might idle in the range for me that you are saying.

a faulty coolant temp sensor can change things too. my "new" ECT read 2* when it was 65* outside! my idle was about 200 rpm higher. when fully warm, it read 93* and was in closed loop.

[Street Lethal]

my idle was about 200 rpm higher. when fully warm, it read 93* and was in closed loop.

Definitely agree with a false temperature reading effecting idle speed some. But if your temperature was reading 93 degrees, it shouldn't have been idling any higher than normal though, as Closed Loop becomes enabled at that approximate temperature (92-94 degrees)....

[torq455]

don't know what to tell ya. that's what happened. just wouldn't idle where it should/used to. conflict with ECT and IAT?

[Juglenaut]

Your Air fuel mixture is rich and the pulse width of your injectors are too high or too frequent and cycle duty is low. Your injectors should be firing 22 times a second at 1325 RPM or once every 22msec, your MAP is low voltage for 1325 rpm.

You may want to verify key on engine off status of your MAP return on pin B using a high impedance multimeter.

You may have a grounding issue test for voltage drop between Battery negative and A terminal of MAP plug.

Check your brake booster. Test for voltage drop between any two points of common like engine and body, engine and negative battery, engine and frame. On a positive note test for DC drop between any two points of common then test for AC voltage from Alt to ground.

It appears as if some noise or EMI is entering the system somehow either ignition or ground looping. I would clean all ground straps good and or replace then. Not all noise is audible and not all noise is Radio interferance.

[n0rt0npr0]

My brake booster makes a growling noise when I am using the brakes...like something is bouncing around inside a cavity or a hard plastic tube...it started making the noise as the high idle has worsened.
But, the power brake booster check valve operates perfectly.
And tell me if I am right: when the map is low, there is high vacuum?

[n0rt0npr0]

grr

I'm done with this. I disconnected mr. iac. Idle is now 712rpm

I only plan on keeping this vehicle for another year and a half, so screw it.

...wonder how the car would run in 10°F weather with that d/c'd?