This just started happening. I think I must have a vacuum leak, or perhaps an intermittent electrical problem.

The auto trans decides not to shift until about 4k rpm at times and is intermittent, applies to all gears even with ECT or OD selected or used in any combination. I have had a problem come back the next day and drive it and it is fine.

The reason I believe it is a vacuum leak is because when the problem occures the breaks seem to be spongy and not very effective. That is until the engine hits about 1500 RPM and the break pedal suddley firms up nicely, the exact way it normally feels until the shifting gremlin comes back.

Any of you heard, seen or know of how to fix such a thing?

 

Depends if the trans is vacuum controlled or cable controlled or electronically controlled...or a mixture of any said above controlling methods. Yes in short.

 

I think the auto trannys are all electrical. Controlled by solenoids and no vacuum at least not from anything in the engine. I'm sure someone with more knowledge will chime in though

 

*Subscribing* I have a simular problem. Brakes feel spongy and need to be pumped to be firm and when it shifts into 3rd or 4th its only there for about 1 second. That maybe just the OD, I dont know. Its also auto trans, so im subscribed. Thanks