Popping At Idle - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Kingtal0n · 04-21-2017, 09:37 PM

You said it settles at 1400. That is a high idle. The popping is probably a lean condition brought on by the high idle. High idle is caused by too much airflow.

You have an air leak somewhere. I would block the IACV channel, the hose that leads to the IACV, with a vice grip, and see if that brings down the high idle. If it does, replace or clean the IACV.

otherwise, there is an air leak somewhere else. Look for broken hoses. If you can't find the leak visually, try soapy water. If that doesn't work, then do a pressure test. Google "boost leak test", basically use a compressor to fill the plumbing with air, to find leaks.

Leaking air (air leaks) cause high idle conditions. Idle is controlled by airflow, not fuel, not spark.

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04-21-2017, 09:37 PM	#8
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,829 Trader Rating: (17) Feedback Score: 17 reviews	You said it settles at 1400. That is a high idle. The popping is probably a lean condition brought on by the high idle. High idle is caused by too much airflow. You have an air leak somewhere. I would block the IACV channel, the hose that leads to the IACV, with a vice grip, and see if that brings down the high idle. If it does, replace or clean the IACV. otherwise, there is an air leak somewhere else. Look for broken hoses. If you can't find the leak visually, try soapy water. If that doesn't work, then do a pressure test. Google "boost leak test", basically use a compressor to fill the plumbing with air, to find leaks. Leaking air (air leaks) cause high idle conditions. Idle is controlled by airflow, not fuel, not spark.