I have had an SES light on once the car warms up for a little while now- just got around to pulling the codes. I got code #29- which I looked up and I belive is this: "Secondary air injection pump circuit voltage was wrong for 26 seconds".The car runs great BTW. Does anyone know what might be causing this #29 code to pop up?

 

The PCM looks at the voltage from the control (Brown wire) lead of the pump relay. The PCM grounds the lead to turn to operate the relay (pump ON), and removes the ground to drop the relay (pump OFF), and lead now shows battery voltage. When the PCM removes the ground it expects to see battery voltage on the lead within 26 seconds. Look for a bad pump relay winding that goes open when the relay warms up. Inspect the harness and connectors at both ends. "A" (red plug)harness,pin 14 at PCM end, and brown wire at relay coil (pin E2). Check fuse #20in Under Hood fuse box. Check for battery voltage at pin E5 of pump relay. Pin (E2) should have either battery or ground, but should never show an open circuit.

The PCM only looks at the pump relay, and does not care wether the pump works or not.

 

Okay I checked the #20 fuse for the air pump under the hood- it was blown, I replaced it. Check engine light is now off, but I dont think my electric fans are turning on at all. The car gets up over the middle of the guage, to about three quarters, than cools off again. I am pretty sure if the fans were turning on I would be able to hear it, as I could hear them on all the time before.However I am inclined to think that a code would pop up if the fans were not activating at all. I guess my question is, how hot is too hot- the car nowhangs around halfway up the gauge,a little over at times- looks like about 200-210 degrees, and how can I tell if my fans are operating or not?

 

Also is it possible that my fans being constantly for so long (with SES light) blew the soleniods or relay etc?

 

The fans are set to come on at around 220 deg. Just let your car idle in neutral and the fans should come on when the needle nears the red line. There is a sticky in the LT1 section on how the fans work.

 

Then I suppose I am just used to the temp the car stayed at before w\ the SES light- because it caused both fans to stay on high all the time, thus the car usually stayed around 170-180 tops. Is a 180 or 160 thermostat a good mod to do to these cars to make them run a little cooler? Or maybe that SLP manual fan switch? Thanks for the quick replies Pete[sm=smiley20.gif]

 

The colder t'stat will only make a difference at highway speed. Whenidling or moving slowly the temp will continue to rise till the fans kick in. The engine was designed to run hot, so don't worry about it, as long as it does not go past 230 deg. Make sure you have a 50/50 antifreeze mix, and a good radiator capto raise the coolant boiling point.

 

Cool thanks for all the help Pete- you are THE MAN!