QuestionQUESTION: We are at witts end with a 97 Madza Milentia, 2.5 Liter v-6. The check engine light come on saying that the egr pressure is restricted. We have cleaned the egr valve (not too cruddy), and found some restriction at vacuum tube from intake. Tested all sensors values, and they seem ok, as per values,and flow is fine thru everything we checked. after cleaning the egr and, intake vacuum sources the light does not come on immediately, takes now 50 to 75 miles to come on leads me to think we improved the problem somewhat, but cant figure what is now happening intermittently. Thanks Robert, Metro Motors Pgh, Pa.
ANSWER: So did you clean all of the EGR passages, or just the egr and what could be reached from there? It sounds like you're one of the many with a similar problem on these cars.
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QUESTION: Hello again, Yes all intake vacuum sources to the egr and sensors were cleaned, and have good vacuum. went thru all the diamagnetic tests as recommended, seems fine. again after driving 50-75 miles light comes on for restricted egr flow.
AnswerActually, the passages that I was wondering about were the ones carrying exhaust gasses. On most cars there is a pipe leading from the exhaust to the egr. There is also a passage into the intake from the egr. The code you're getting indicates that these passages are blocked. I suspect that you have already cleaned these passages, but I just want to make sure. If all of the exhaust passages are clean, then perhaps the egr is simply under-performing and needs to be replaced.
