Transmission Won't Engage After Cold Start

I drive a 1994 Buick Skylark Custom with a V-6 engine, automatic transmission, and 130,000 miles on it. A couple of months ago I had the car in for some air conditioner service (I’ve gone to the same garage since I bought the car in 1996)and while they had the car they checked it for any other problems. They told me the transmission fluid needed changing (which was probably true since I can’t remember the last time it was replaced, if ever). I gave them the okay to proceed and they flushed the old fluid out and replaced it with new. Ever since then, whenever I do a cold engine start (the car having either sat overnight or having sat for several hours after I have driven it during the day) the transmission does not engage immediately after I shift the car into gear. I usually have to let the engine run for a minute or two before it will engage in reverse or drive. I asked the garage owner about it and he couldn’t figure out why it was doing that. I’m skeptical about letting him check the problem out further because I think the problem was caused by them in the first place.

I never had this problem with the car before. I was always able to start it, then within seconds shift into gear and it would engage. I checked the transmission fluid level and it was in the okay range. Is it just a coincidence that this problem started immediately after the transmission fluid was changed, or could that process have caused the problem? Other than having to wait a minute or two each time I start the car there doesn’t appear to be any other problems with the transmission.

Thank you for your advice.

Tom Doniphon

If they just drained the old fluid, changed the filter, and then added new fluid I’d say the transmission service didn’t cause the problem. IF, they “flushed” the transmission as you described then the flushing process can dislodge dirt and debris in the transmission which can find a way to lodge in critical passageways in the transmission. So, if flushed, yes the service could have caused the problem.

The root of this is that you can’t remember the last time the trans fluid was changed in a 14 year old car with 130K miles on it. Lack of maintenance on the transmission is likely the cause of the problem, why it happened now is because of the “flush”. If the trans had regular fluid changes like every 30K miles there would not have been the junk in there to get stirred up by the “flush”.

It sounds like the fluid is leaking out of the torque converter when the car is stopped. When you start the car it takes time for the torque converter (which is essentially a pump) to build up enough pressure to run the transmission. As long as the condition stays the same you may just have to live with this until the transmission fails completely. A fix could be expensive and it may last like this a long time.

Uncle Turbo is correct.

If the fluid had not previously been changed in the car’s 15 year/130,000 mile history, then a “flush” could definitely cause a problem by circulating the crud that had built up in the transmission pan during those 15 years. However, rather than blaming the shop that did the flush, it would be more accurate to blame the car’s owner for ignoring the transmission fluid changes that should have been done every 3 years/30,000 miles.

At this point, an expensive transmission rebuild is very likely going to be needed.
For future reference, please remember to have your transmission fluid and filter changed every 3 years/30,000 miles (whichever comes first).
Regular maintenance is invariably far cheaper than repairs.


When the transmission was flushed did they drop the pan and change the filter before they flushed it?? If not, it sounds like they got some trash where it shouldnt be, for instance, hanging up a pressure regulator valve. This is why I badmouth flushes so often. Flushing could be a good thing if done regularly, and properly. There are way too many unqualified people out there with flush machines who are just tearing up transmissions left and right then just shrugging their shoulders when the car owner comes back with transmission problems. Shops with flush machines are keeping my shop busy. Right now I have 4 on the shelf waiting for tear down that are there from recent flushing, 1 in the vat, and 1 in the assembly room going together. All those taken in in the last week. On the flip side there are also car owners who dont service their transmissions on a regular basis, in fact they dont even think about their transmissions until they start to give problems. Only then do they do a service and usually that is too late. Automatics need to be serviced with new filter and fluid every 25-30k miles. Now, theres a third side to this coin. Car manufacturers, in their great effort to sell their cars advertise that their cars are so maintenance free or maintenance friendly that they increase their service intervals to astronomical levels, “Lifetime” transmission fluid??? 60k fluid change?? 90k?? 100K??? I dont think so. 25-30k max. Regardless of what the owners manual says.