Check Engine Light On

[bolokid]

I am getting the recently purchased 93 Festiva ready for Westiva and then onto Madness. I noticed the O2 wire had been cut off so I replaced the O2 sensor with a new Denso O2 sensor. The idle speed is 1600 rpm and will not slow down even though the idle screw is turned down all the way.

I took the car out on the highway for the first time this evening and the CEL came on. I read the codes and have code 08 and code 15.

How do I slow the idle down?

New O2 sensor bad? VAF bad also?

Thanks.

[dalebwilson]

Is it a stock B3? If so, idle is controlled by the IAC valve based on engine temperature from the ECT sensor in the intake manifold and the IAT sensor in the VAF. Base idle and ignition timing must first be set (750 rpm) while the ST1 connector is grounded and engine is warm. You can make slight adjustments with the air bleed valve under the round rubber cap in the top the intake manifold with the understanding that idle also affects ignition timing. The dash pot valves near the throttle cable attachment are prone to sticking and should be cleaned and lubed as these stick slightly open and cause high idle.