Trans downshifts with gas tap

check fluid levels add if low..if not replace filter in transmission..od should return.. make sure detent(downshift )cable is not hung up either..connected to the accelerator linkages..good luck

shift sensor in trans bad take the tarns apart . well drop pan n fluid the drop out the valve body then u can see the shift sensor

Hello
The Engine and Automatic Transmission (not applicable to manual transmissions) in this vehicles drive train are fully electronically controlled by a computer called the PCM and TCM (Power Train Control Module, Transmission Control Module). When a problem like this or other drive-ability related problems occurs the computer stores a record of the problem (there are of course some exceptions to this, like the fuel pump, engine coolant temperature sensor and MAF sensor for instance) in the form of a fault code in its memory, to read these fault codes you must have the systems memory scanned with a special tool. Once the fault code(s) are read you then must perform the appropriate diagnostic testing to find and resolve the problem(s) DO NOT REPLACE ANY PARTS UNTIL A TRAINED TECHNICAIN HAS DIAGNOSED THE PROBLEM TO AVOID SPENDING YOUR HARD EARNED MONEY ON PARTS THAT MAY NOT CORRECT THE PROBLEM. Also always check fuel pressure for correct spec for your make and engine type.

you have checked the fluid level right?

replace computer not telling trans when to shift right

I believe you have a 4l60e transmission.Do you have a chck engine light? The unit may have a 3-2 downshift solenoid going bad or a possible band ''servo'' leaking. The band applies in 2nd and 4th.You may also have a shift solenoid starting to malfnction......Best

This model has a tranny computor under the dash on the right side screwed to the bottom of the dash. If I remember correctly, there is also an inline fuse attached to the harness. Check the fuse.

Dear sea_lion42, Friday 2-20-2009 11:22pm EST (USA)

Check your transmission fluid which is usually done with the engine warm and running!
If the tran fluid is low add some Lucas Trans Fluid from your local auto parts store!
The knock makes me believe your low on trans fluid!

jack

The aerostar tranny cooler sits too low away from the trans and tends to become blocked and restrict the flow to the tranny It could not hurt to remove it and flush the cooler out I have had a few aerostars and I have had to flush them all,the tranny fluid came out very dark and smelled very burnt it may not solve your issue but maybe. It has solved a shifting issue for me the 1-2 is smooth as silk now.

you may have damaged the overdrive gear, a local transmission shop would be your best bet. for good troubleshoting and estimate.