Re: When you start the engine cold do you hear the SAI pump runnning? Some are quiet but not so quiet...

Following the major surgery to replace my engine, I can't seem to get rid of a secondary air system failure reading on my mechanic's OBD monitor-- which is preventing me from gettting the car inspected. Following replacement of the engine and related repairs, naturally, the OBD showed complete failure on all readings, but I have driven the car more than 200 miles, in all kinds of traffic, and everything has reset except secondary air, which still shows failure. There is no error code showing (i.e., cats), no misfire readings, nothing at all to show a problem except this one reading. Any ideas?

2001 Base, purchased in 2004, replaced engine at 130K+, RIP 2017

Quote
JackintheBoxster
Following the major surgery to replace my engine, I can't seem to get rid of a secondary air system failure reading on my mechanic's OBD monitor-- which is preventing me from gettting the car inspected. Following replacement of the engine and related repairs, naturally, the OBD showed complete failure on all readings, but I have driven the car more than 200 miles, in all kinds of traffic, and everything has reset except secondary air, which still shows failure. There is no error code showing (i.e., cats), no misfire readings, nothing at all to show a problem except this one reading. Any ideas?

that you should not be able to hear it.

I'm puzzled by the absence of a CEL and DTCs.

The SAI readiness monitor isn't reset by driving. It is reset by during a cold start having the system working properly which is IRRC determined by the presence of excess oxygen in the exhaust then when the SAI is switched off the excess oxygen going away.

Let me think about this some more.

In the meantime all I can suggest is double check the wiring and hose connections. The coolant temp and possibly the intake air temp are used to know if it is cold enough to turn on the SAI pump. Also, a rather odd behavior I've observed with my car is while the SAI pump comes up at cold start if I turn off the engine shortly after startng and then restart it the SAI doesn't come back on. I do not do this but only rarely so there could be times when the pump does come back on. But I have noticed this by the absence of the pump's running on the subsequent engine restart.

Sincerely,

MarcW.

Marc -- Thanks -- let me run this by my guy.