about two months ago my car started to miss and pop through exhaust. i changed wires, plugs, 02's, coil, tested ICM=good, new IAT sensor, and the opti is used but has been working fine for about a month or so. any ideasas to what it could be cuz my car runs fine for about 10-20 minutes then just starts acting up. i really need this damn car running before school starts again cuz i usually drive about 50 miles a day, or i might have to sell the car . thanks for any help guys!

 

Hey man, I replied over on the SD board, here's the same thing:

Description Page
Diagnostic Chart

Sorry about the delay, things been crazy. Ok, diagnosing the DTC 23:

Well, after studying the charts, I hate to say it but I don't think an Ohm Meter is going to be a ton of help here.

Set it to "Ohm" and connect either end to each terminal on the IAT (disconnected of course). Compare the Ohm reading to the chart on the diagnosis chart page, you'll need to know what the ambient temp is at the time the reading is taken.

For the testing of the wiring/computer, use a paperclip and straighten it into one big "U" shape. Enter each end into the IAT harness, jumping the two ends together. Start the car and see if a code sets. This should set DTC 25, IAT High. By jumping the terminals together your's simulating an ambient temp of 130+ C. This will set the DTC 25. If it sets the code, the computer and wiring are OK.

This would be MUCH easier to do if you had a scan tool. That way you could just watch the results. If you have any more questions just let me know.

 

Pull the sensor out of the bellows.... stick it in ice water (cubes floating in water, well stirred) and it should give you 9,420 ohms. Stick it in boiling water (assuming you're at sea level) should give you 177 ohms.

With the key on, check the harness connector for voltage.... should be about 5V with no load.

"low temp" code generally set for an open circuit.... infinite resistance = temperature more than 40deg below "0".