Kevin
1988 leSabre CHECK ENGINE light seems to come and go as it pleases. Has weeks where it's off and on constantly...and now as I type I haven't seen it in a week or more, but inevitably it will come back on-off-on, etc. Always seems to come back on not at cruising speeds for the most part, but on decel with little or no load...say when braking and decel around 30-25 mph. Was told this type of behaviour was typical of flaky/blocked EGR valve. Any thoughts? Also the thing pings on accel that only higher-octane seems to alleviate. And i know that is very often EGR-related. thanks.