1975-76 230 Models
- Remove EGR valve. Connect Red vacuum line to the removed valve. The EGR valve stem must lift off its seat. If not, check vacuum source. If vacuum is present, check valve stem and diaphragm for damage.
- If necessary clean EGR bores in intake manifold with a 0.40" (10 mm) drill, remove exhaust deposits from distribution tube and clean out with compressed air. Replace EGR valve if necessary.