Wow.... very impressive indeed. Thanks so much for the valuable info. My local smog station did a pretest and the car did pass the test. But he did insist that in order to pass the full test i'll have to get the check engine light looked at and i'll also need a new gas cap. The egr and check engine light problem was both discovered by the dealership last time this car was in service.

hmm.... I just rechecked the log notes on the dealer service receipt from last time, here's what it said:

"client states that the check engine light is on (on or off) egr malfunction. checked for codes. found p0400 egr flow malfunction. ck egr system, valve and vacuum to egr valve are normal. found no rpm drop when activating egr valve, egr tubing is cloged at intake manifold. need to remove tube and clean. cleared code for time being. client will address later."

Looks like you were dead-on about the egr problem, doc. My question now is: will i be able to clear up the tubing myself? or should i leave this job to the professionals?

Thanks again to everyone for their helpful inputs!!

Mars