Question about 1990 Buick Riviera

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1990 Buick Riviera Transmission won't shift out of low.

My 90 Riviera was working flawlessly up until yesterday. Tranny oil was leaking into the radiator, so I installed a big transmission cooler, and bypassed the radiator altogether. Upon completing the job, I took it for a test drive, and the transmisssion wouldn't shift out of low. Brought the car back home, and un-did all the work, and it still won't shift. What the heck did I do?!! 166K on the car.

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The vacuum line to the modulator need to be connected.

Posted on May 12, 2009

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Your in-radiator transmission cooler has failed, and most likely you have gotten coolant in your trans along with the trans fluid in your coolant.

The external cooler you installed is a good idea, on a couple of levels. First, it separates your fluids, so no more cross contamination. Second, it keeps engine heat separated from transmission heat, allowing both to run a bit cooler.

If you haven't already, you can drain and flush BOTH the engine coolant and transmission. For the trans, you will need to do it a couple of times, because there is a lot of fluid in the torque converter (the part between your engine & trans) that normally doesn't get drained during a trans fluid change. Be sure to change the transmission filter each time.

If this doesn't work, then I'm afraid that you will have to rebuild your transmission.

Posted on Apr 19, 2009

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On my Vauxhall/Opel Senator I snagged a cable from the auto box which left the car in a 'limp home' mode. I'm no mechanic but once the cable was re-attached the car was fine.

Posted on Apr 19, 2009

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