Hard 1-2 shift
#1
Cant this thing go faster
Thread Starter
Hard 1-2 shift
I have a 06 XL with 186000KM and a 4R70E transmission (according to Etis). Recently I have started getting hard shifts from first to second gear. It doesn't happen all the time but more often than not it occurs when the engine is cold and/or I'm turning right. It doesn't seem to be slipping, just staying in 1st longer until it finally shifts hard. I have been slowly changing the ATF using the pan drop method and the problem has not gone away or become worse. Doing some research it seems the likely suspects are:
1. Sticking or damaged check ball-valve
2. Sticking 1-2 shift valve
3. 1-2 accumulator leaking or binding
4. Faulty shift solenoid
How should I check these? Are there any other things that might be causing this?
1. Sticking or damaged check ball-valve
2. Sticking 1-2 shift valve
3. 1-2 accumulator leaking or binding
4. Faulty shift solenoid
How should I check these? Are there any other things that might be causing this?
#2
Senior Member
iTrader: (1)
I have a 06 XL with 186000KM and a 4R70E transmission (according to Etis). Recently I have started getting hard shifts from first to second gear. It doesn't happen all the time but more often than not it occurs when the engine is cold and/or I'm turning right. It doesn't seem to be slipping, just staying in 1st longer until it finally shifts hard. I have been slowly changing the ATF using the pan drop method and the problem has not gone away or become worse. Doing some research it seems the likely suspects are: 1. Sticking or damaged check ball-valve 2. Sticking 1-2 shift valve 3. 1-2 accumulator leaking or binding 4. Faulty shift solenoid How should I check these? Are there any other things that might be causing this?
#5
Cant this thing go faster
Thread Starter
OK, I took a multi-meter to it and the resistance of pin 1 and 4 are opposite of each other. When the throttle plate is wide open one measures a very low resistance and the other shows a high resistance. Now I'm using a cheap multi-meter with a low refresh rate but it seems to change smoothly. The stepper motor that actually moves the throttle plate seems to make an odd clicking sound when in anything but idle, could this be throwing the sensor off?
#6
Senior Member
iTrader: (1)
OK, I took a multi-meter to it and the resistance of pin 1 and 4 are opposite of each other. When the throttle plate is wide open one measures a very low resistance and the other shows a high resistance. Now I'm using a cheap multi-meter with a low refresh rate but it seems to change smoothly. The stepper motor that actually moves the throttle plate seems to make an odd clicking sound when in anything but idle, could this be throwing the sensor off?
Its possible.. There is actually an additional TPS sensor on the motor of the throttle body. It is just a microchip that reads from a magnetic tone ring.. The 2 TPS sensors work together, but it's more Likely that the one bolted to the throttle body will fail.. Is the throttle body clicking when actuated manually? Or electronically?
This only happens on a cold motor, but does it go away on a hot motor?
The symptom showing up while turning may be a sign of low fluid.. When was the last time you changed the filter?
Was there any big particles on your magnet when you dropped the pan last?
You should always warm up your vehicle after a long rest prior to driving, even on a hot day...
#7
Cant this thing go faster
Thread Starter
The throttle body clicks when actuated electronically, but doesn't seem like its sticking. When its clicking if you touch the throttle plate you can actually feel it when it does it.
The hard shift happens intermittently whether the motor is cold or warm, it just happens more often when its cold.
The filter was changed less than 6000Km ago (a month, month and a half at the longest) when I added a drain plug ( thanks for the write-up btw.
The fluid shows as full on the trans dipstick when I checked after reading a post that mentioned that might be the cause.
As for the magnet it was covered completely in superfine particles, but given what I know from previously owned vehicles it has the expected amount for the mileage.
The hard shift happens intermittently whether the motor is cold or warm, it just happens more often when its cold.
The filter was changed less than 6000Km ago (a month, month and a half at the longest) when I added a drain plug ( thanks for the write-up btw.
The fluid shows as full on the trans dipstick when I checked after reading a post that mentioned that might be the cause.
As for the magnet it was covered completely in superfine particles, but given what I know from previously owned vehicles it has the expected amount for the mileage.
Last edited by technokami; 08-07-2014 at 10:00 PM. Reason: clarification