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DISCUSSION => Engine + Driveline => Topic started by: stillmatick on February 17, 2011, 03:42:56 AM

Title: idle problem
Post by: stillmatick on February 17, 2011, 03:42:56 AM

I used to get this idle surge from 800-1200rpm but after replacing 02 sensor it went away for couple weeks and now is back again.

Only does the surge when motor is fully warm or some days it doesn't surge meaning motor run fine.

When it does surge i turn the a/c on which will make the surging stop.

What can cause this weird surging idle??

Title: idle problem
Post by: stillmatick on February 17, 2011, 04:02:05 AM

no check engine on and all vac hose under manifold are new.

Title: idle problem
Post by: DesktopDave on February 17, 2011, 07:21:11 AM

The A/C will bump up the idle speed to compensate for the compressor load on the motor.  It might pop the ICV wide open.  Did you clean out the ICV recently?

Title: idle problem
Post by: stillmatick on February 17, 2011, 08:13:38 AM

Quote from: DesktopDave;101585

The A/C will bump up the idle speed to compensate for the compressor load on the motor.  It might pop the ICV wide open.  Did you clean out the ICV recently?

yes when I replaced the o2 sensor,guess I clean it again and see will that help.

Title: idle problem
Post by: stillmatick on February 17, 2011, 03:34:09 PM

think iav is going bad,but everything is working perfect now.

also does 318is 1991 use air temp sensor?