Having problems with your 2003 Ford Focus ?
2003 focus with rough idle and tach surge. No code yet although problem been there a couple weeks. Took the vacuum hose off the egr valve and rough idle/surge cleared up. Pending problem on obdII still there. Vacuum hose had suction at idle. Maybe the pressure switch the problem?
Carbon build up in the egr passages and the hose is collapsing
Repair Help & Product Troubleshooting for 2003 Ford Focus
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