I just had my LH controller repaired and the profile is now different.

Now, it will not kickdown if the gear it is going into will result in the RPMs being higher than 4000. In other words, it will not kickdown to first unless I am below 25mph.

Previously, it would kickdown even if it resulted in the rpms in the 6000 range (about 40MPH) and then immediately upshift as it hit 6600 (about 45MPH).

The new profile seems much easier on the transmission, maybe a little less fun to drive. It still revs to 6600 rpms before the shift so that is good.

What profile do you guys see in your S4?

 

I got a rebuilt LH ecu from Part Werks, Chicago. They didn't send back the same one I sent them. The only difference I noticed was that Sharky starts easily on the first bump when cold. Other than that, shift points and performance seems the same.

 

Jerry,
The LH controller does not activate the kickdown solenoid; it deactivates it via the KD relay. The power flow is from the KD switch (gas pedal) thru the KD relays normally closed contact, (the relays always on) to the KD solenoid... at 6600RPM, model dependent the LH energies the KD relay, breaking the connection between the KD switch and the KD solenoid,. Forcing an up shift to lower the RPMs. At a full throttle kick down up shift you should reach red line, 6600RPMs before the rev limiter cuts the power...

If your KD does not work above 4000RPMs the LH is defective, or adjusts the TV cable. I would try another controller.

<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

 

You could pull the kickdown relay and put a jumper in, then see if the kickdown is back. That would tell you whether the problem is with the ECU.

 

I have driven a lot more since I made the first post. Here is the latest.

The kickdown works fine into 2nd gear. For example, if I am running 60 or so and kickdown it will result in the rpms moving up to 5000 ( in 2nd gear) and it will proceed to 6600 before shifting to third. I understand this to be normal operation for an S4.

The difference is it used to do the same thing in first but no longer does it. In will not shift into first unless the result is the rpms will be below 4000 ( I also understand this to be standard for the S4). Before I could be running 40 mph and it would kickdown to first anytime the result was below 6600. Was quite a jolt to kick it down and hit first gear at 6000 rpms.

So Steve, if I understand correctly, my original controller ( not the one I just got back from the repair shop) which was modified/rebuilt by a place in NC many years ago must have been set up different than the stock controller. It must not have had the limit of 4000 rpms in first but rather changed to 6600 like the other gears.

I do not know enough about the Controller to tell if this makes sense. I also do not know what was wrong with my controller since they sent me a different unit nor can they tell me. I am trying to get my original controller back, hopefully repaired. I marked it in an obvious manner so I would know if they switched units and they did it anyway. I was told they would repair mine not give me a different one which was the only condition that I would allow them to repair it under.

Whoever ends up with my controller will probably rave about the repair work On the other hand if you get it and want to trade, let me know.