The most calls for help we receive is from shops or mechanics after the
worked on the cvt transmission.
It is a complain of " hesitation in the accelerator process"
here bear in mind after a repair an Adaptation or learning process has to
be performed. The hesitation on the acceleration is the reason that the clutch values from
the computer are not recognized and have to be relearned, you perform this process
in the time you test drive the car and activate the brakes and simulate a
Torque of 15 Nm on the clutch.
Also many
Audi owners with the CVT Multitronic transmission calling
for help the experience some problems when the Car comes to a stop, the car
shakes and hesitates and seems Not to respond to the accelerating pedal
anymore !
The problem only exist in the D or S gear selection.
Way? Because this problem cannot occur in the Tip selection, because
here the unit shifts earlier in the first gear!
In selector position D or R the Rpm doesn't rise up anymore and the car
won't move at all, he is NOT responding to any accelerator pedal.
After one drive cycle, this means, one turning of ignition and turned on
again, the car resets itself and will drive again.
The most problems we experience with the CVT transmission, is a failure in
the valve body, (hydraulic control unit). The dirty oil with particles in
the oil cause a sticky valve body with hydraulic malfunction. Instead of a
smooth movement of the reaction valve, a high pressure rises up on the
sticky reaction valve and forces the valve to close with a bang shortly
before the car comes to a stop and should shift in the first gear, but he
doesn't !
It is Important to check your transmission fluid, if you have metal
particles in your oil, in the size of one millimeter or more, save your time
and money, you need to replace your transmission. If the oil has a burnt
smell, it is likely that your frictions are damaged and need to be replaced
with a new
filter, oil etc..
To find out now, if your Valve body or something else is the problem
in your transmission, let me give you the following hints, this is more for the
professional mechanics with the proper tools.
Before the test drive, read out the value Block 65, write down these values
and then turn off and on the ignition and perform a test drive with a
minimum of twenty stop and go cycles (really stop to "0"). Read out again
the Value block 65. If the result is smaller or 0 at on the first reading,
you have no problems on your valve body,-is it higher you need to replace your valve body.
The value Block 65 counts the reaction of the safety valve (SIV) by
known hydraulic malfunctions, to reduce the clutch pressure in the shortest time. After too many counts, you have to reset the computer (value
Block 65). For this reason you have to cycle your ignition on and off.
By the earlier CVT transmission to 2003 after this year a new valve body
design with self flush capability is designed.
herb at eurotrans
www.europeantransmissions.com