I have 98 Camry w/ 70k miles. CEL came on 2 days ago. Went to Auto Zone for free diagnostic, which displayed "EGR Insufficiency."
The CEL came on immediately after a gas station attendant put in premium when I had asked for regular. This may be a silly question, but could this cause such a reading?
Also: can anyone tell me where I find the EGR and how difficult it is to remove and clean?
What tests can be done to pin down problem?
If the EGR itself is bad, is it expensive?
Are there any other possible causes of problem?
Thanks.