have a ford mondeo auto 1800 Lreg 1993 it doent always in top gear and sometimes takes a long time to engage any gear (feels like a clutch slip) or will rev to limit before changing it seems to happen with almost any driving style the gear oil has been change but no diffrent
All the shift points are electrically controlled. Common faults are no/slipping 2nd and 4th (band broken or partially broke). Split drum giving the slip you seem to describe. Transmission range position switch. Low ATF level could cause the bang into Drive. The range switch if faulty can give no or limited sometimes random up shifts and even rev limit on the engine.
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