Just installed PCIII/O2 Eliminators, SE Air Filter, V&amp\\;H Ovals, installation was slick and fairly easy (not picked up a wrench for years) and all appeared well until I noticed that the Check engine Light is permanantly lit when the engine is running.
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Checked the code and it states P0661, reset has no effect as it just appears after a short period of the engine being started.
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Anyone seen this before and can throw some light on the direction I need to be looking?&nbsp\\; checked all connections and O2 plugs and all seem well connected, engine seems to run well also (apart form the usual decel' popping that I see seems to be a common factor).

 

Are you sure you need O2 eliminators when you use the PCIII?

 

If you have an O2-equipped engine you can tune the PC to provide just the right fuel changes so that the stock-tuned ECU thinks it is providing perfect levels of stock fuel to your new breathing stuff. But then it will still run at the factory-lean settings. Best to eliminate the O2 sensors with the PC-III to avoid adaptive fueling troubles.

 

P0661 looks like HDI intake flapper solenoid. Either measure the coil resistance and put a similar-value resistor across the connector or attach the solenoid to it and stuff it somewhere.

What did you do with the one on the exhaust?

 

Glens,&nbsp\\; think from further searching that you are spot on with the diagnosis of the Active Air intake solenoid, will reconnect it ASAP to check it out.

The active exhaust is still in place, the PC instructions make no mention of it's removal, is there a + effect by removal?