My check engine light came on last week w/ a code 0302 but the next day the engine light was off. Today the engine light came on again w/ the same code 0302. I just want to know if it's safe to drive around w/ an egr problem? Also in the Hayes manual they tell you it could be like 5 different things wrong w/ an egr, like the connectors, the valve, the sensor, etc. I want to try and fix this on the first try so is there usually a main problem w/ the egr. thanks