On cold start up the SAI pump on '02 Disc II comes on and operates properly. However after car has been driving a while and is warmed up - the pump comes on and turns off in short bursts for 10 seconds or so.After a few cycles of this- all is fine and car drives well. This happens every morning-almost as if a "timer" is acting as a trigger for this to happen. There are no codes when scanned and no lights on dash.

Is this a faulty relay? All the connectors to the pump look fine and nothing looks damaged,wet or corroded that I can see.

Thanks for your help.

 

Mine used to do the same thing. I'm not sure what changed, but it doesn't do it anymore. From what I remember though after doing some research that is pretty normal thing to happen.

 

The pump turns on when its needed.

 

I thought the SAI was only supposed to trigger on during cold starting for emission purposes. If that is true, than there is no way it should be turning on when the engine is warm running condition.??

 

It will turn on as the ECU needs it to lower the emissions.

 

it does the first cycle at cold start up but as Mike said if the ECU reads that your emissions are to high it will kick it on at any time. bballjames was there any injection cleaning done or any changes along the lines of your emissions system that may have caused yours to straight up?

 

Ya I replaced my O2 sensors. Could that have changed it? I haven't done anything else that I think would be connected...

 

Thanks for the replays. I thought that the sai is triggered to the on position with the coolant temp sender. When the ground circuit is open/ close that sends a signal to the sai. So it's all based on coolant temperature. If the ECU gets that signal and controls it- sounds possible that there is a loose or corroded connection. The pump works obviously and there are no codes. I am going to explore more and will post my results.Thanks.