Q: Automatic transmission problems after engine swap

asked by on September 26, 2016

My Mitsubishi Space Wagon 2001 engine was replaced with a 2000 Mitsubishi Gallant engine and now the automatic transmission keeps reviving up once it is in gear 3 before engaging, and revs up at exactly 50 km/hour, then same thing when slowing down too.
My car has an automatic transmission.

Hello there, thanks for writing in.

If the issue occurred after the engine was swapped, then it may be possible that the issue is related to the swap. The symptoms you describe can be caused by a variety of issues from the swap. If you suspect the problem is transmission-related, a few things I would check are the fluid level, shift solenoids, the pressure switch. Similar symptoms can also be caused by problems with the vehicle’s engine management system.

If you would like help diagnosing this issue, consider having an expert automotive technician from YourMechanic come to your home or office to inspect your vehicle for you, and make or suggest any repairs as needed.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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