idle issues

[nytescion]

Ok here is the deal. I've tried setting idle with grounding the two prongs (under hood, and diagnostic port) idle doesn't change at all when grounding these two prongs. idle doesn't change at all when messing with the biss screw after doing it either. All me sensors under hood are plugged in and i have no CEL's.

The car will idle high upon start up (14-1600) until the car is warm then drop to 1000. This is where my Kaydiver chip is set to. After driving or idling for a while the idle will drop to around 6-700rpm and will stay there no matter what. The car will not die but just idle low. What should i be checking to find out whats going on.

 

[ilco187]

is the throttle body grounded with the factory ground strap, high idle seems like might be the fiav,

 

[nytescion]

Not the factory ground. I had to make a ground. I think you misunderstood me. My idle is suppose to be 1k. It's idling between 6-700rpm.

 

[jeffo]

Idle issues like that are usually an indication of a non-functional ISC motor. Have you checked your's, as per the VFAQ? Have you tried logging the ISC steps, to see what its doing? If the ISC tests OK, it could be a problem with the ISC drivers in your ECU. IC105 or IC107 are often fried, either due to a bad ISC, or a leaky 47uF cap.
keydiver

 

[nytescion]

Idle issues like that are usually an indication of a non-functional ISC motor. Have you checked your's, as per the VFAQ? Have you tried logging the ISC steps, to see what its doing? If the ISC tests OK, it could be a problem with the ISC drivers in your ECU. IC105 or IC107 are often fried, either due to a bad ISC, or a leaky 47uF cap.
keydiver

No haven't check the ISC. I'll try to do so tomorrow. I don't know if i can log the steps with my logger program something I would have to check on. Where would I look on my ECU to find out if these areas are damaged?

 

[jeffo]

Back in the righthand corner, near the 4 green capacitors, you will see 6 black vertical driver chips, all in a row. IC105 and IC107 are the ISC drivers. Look for burned or bubbled ones.
keydiver

 

[nytescion]

well IC105 seems to have some brownish stuff around 5 of the 8 pins so i suspect that it's burnt. How do i go about fixing this?

 

[jeffo]

If what you are seeing is down around the pins, that's probably just some of the conformal coating. What you are looking for is a bubbled, black spot on the chip itself. Its usually quite evident when one of the drivers has popped. Its often accompanied by lots of smoke inside the ECU.

 

[nytescion]

hmm ok well nothing is burned or bubbled the way you describe it. I guess next will be testing the resistence in the ISC itself and the volt test.

 

[nytescion]

Everything checked out resistance wise. i just gotta get a 6 volt battery and hook it up the isc to see if it vibrates at all.

 

[nytescion]

ok just did the volt test. Nothin moved or vibrated once applying the positive leads to pins 2 and 5 and negative to 3 and 6. So i would assume i need a new Sensor. I could use the same way to test isc sensors off the car before purchasing it i would assume?

 

[Hardin]

Might wanna check the ignition (spark plugs). Or the Idle sensor...

-Hardin

 

[nytescion]

I checked the voltage going to the sensor. If using a 12volt battery will destroy the isc motor then why is my car supplying 11.53 (12v) volts to it?