Stock 210 TCU questions
Stock 210 TCU questions
Ok, my main question. If I go to a mechanical injection pump (or come up with my own control of the electronic one), how does the TCU respond? Will the absence of the stock injection control cause the TCU to stop altogether, go into limp mode, what happens? Surely this has been tried on here many times! Does the TCU need can bus communication with the ECU to function?
Thank you,
Jason
Tubularfab
02-20-2015, 07:18 AM #1Hello - I have been searching the various forums for a while now, and have not been able to find the answers to some questions I have about a 1997 E300 and the factory powertrain controls for the 722.6. Most of this is because most Mercedes forums are only about doing it exactly as Mercedes intended - maybe I finally found the right forum!
Ok, my main question. If I go to a mechanical injection pump (or come up with my own control of the electronic one), how does the TCU respond? Will the absence of the stock injection control cause the TCU to stop altogether, go into limp mode, what happens? Surely this has been tried on here many times! Does the TCU need can bus communication with the ECU to function?
Thank you,
Jason
whipplem104
02-24-2015, 09:01 PM #3You cannot run the stock tcu without the engine control unit. You would have to go with a standalone unit. You would also loose a lot of other functions, such as A/C and your instrument cluster would not work. Traction control would not work. etc.
Or, am I going to have to do something crazy complicated to simulate the rack position signal the ECU would expect to see for a given quantity adjuster output level from the ECU?
Another way to ask - imagine everything is connected as stock, but I had the side off the pump and could manually override the rack position (not how I am going to do it, but for argument's sake). Will the TCU go into limp home mode (2nd gear) in this scenario?
I'll probably have to just start playing and see what happens, but figured someone had to have tried already. Playing with an old pump yesterday we were able to both read the sine wave return signal from the position sensor and move the rack via the actuator smoothly.
BTW - I could not care less about traction control - this (at the moment) is a normally aspirated '97. Traction control isn't much of a problem!
Thank you!
Jason
Tubularfab
03-03-2015, 07:16 AM #4Ok, I didn't word that quite right. I don't plan on getting rid of the stock ecu, but I would like to control the pump with a separate controller. Is the ECU going to freak out and send a fault code that would disable the TCU? The ECU will still see everything it sees now, it just won't have closed loop control over the pump.
Or, am I going to have to do something crazy complicated to simulate the rack position signal the ECU would expect to see for a given quantity adjuster output level from the ECU?
Another way to ask - imagine everything is connected as stock, but I had the side off the pump and could manually override the rack position (not how I am going to do it, but for argument's sake). Will the TCU go into limp home mode (2nd gear) in this scenario?
I'll probably have to just start playing and see what happens, but figured someone had to have tried already. Playing with an old pump yesterday we were able to both read the sine wave return signal from the position sensor and move the rack via the actuator smoothly.
BTW - I could not care less about traction control - this (at the moment) is a normally aspirated '97. Traction control isn't much of a problem!
Thank you!
Jason
whipplem104
03-03-2015, 10:00 AM #5It depends on if the stock ecu is using this information for torque calculations. Which it might be or it might be using the air mass sensor. I would imagine that it uses engine rpm vs fueling to calculate torque. If it new where the rack position was but did not have control over it, that might work. Just depends on what the fault protocols are.
1 Guest(s)
1 Guest(s)