I have a 2007 Mazda5. Lately when climbing a steep hill the downshifts are delayed. The worst is from 3rd to 2nd. The engine bogs down and needs more torque, but it won't downshift when it should. When it finally does, it does it with a bang.

I can work through the hill by moving it into manual mode when I think it should downshift and the lift the throttle a bit to ease up and click it into 2nd.

There is no dash lights indicating an error code. Can a transmission code be read if there is no light?

As a search around, I see reference to the shifting solenoids, but not exactly this problem. Some similar shifting problems, but no one has mentioned this exact one.

I had the fluid changed, which smoothed out the shifts all arround, but did not solve it.

Interested to hear if this has happened to anyone, or some ideas.

Thanks,
Stefano in California

 

I have a bit more info to add.

It seems to be an rpm based downshift problem. I tested by slowing down from coasting. The gear indication light shows 4, then 3, but stays in 3 all the way till almost a stop, and then shows 1.

If I am coasting and step on the gas, I can get it to downshift from 4th to 3rd, and again from 3rd to 2nd going even slower and another push of the throttle. So the throttle position or kickdown switch does seem to work as it should.

So what component would cause it to not downshift into 2nd when it needs to by rpm, but will work just fine with a blip of the throttle, or in manual mode?

Thanks,