Strange happenings with an Omega - Mike200
A family members 2.5 V6 (N reg) Vauxhall Omega has got some strange problems.

The car seems to have a gearbox problem. Driving along, it will all of a sudden drop out of gear, a quick stop and re-start clears it. Any ideas?

Also, recently, the car has refused to start intermittently. When the car does start (whether after problems or not) it revs on its own and along with this comes a kind of growl, quite loud, which sounds like exhaust baffle or induction roar. Again, any ideas?

Any help would be appreciated, as this car has got to do a 600 mile trip to France in a month, and we don't know where to start!!
Strange happenings with an Omega - king arthur
I'm not an expert on Omegas and don't know which box it has, but the dropping out of gear and needing to be restarted sounds like a case of pickup filter getting clogged while driving. Probably needs the ATF changed and filter cleaned, which should be possible if you can remove the tranny sump.
Strange happenings with an Omega - prm
Could also be the gear selector switch or gearbox ecu.
 

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