Celicasaur

For a while now, my car doesn't respond how it used to in first gear from a dead stop.

Like, with traction control turned off (or even in 'sport' mode) I used to find it nearly impossible to control a launch in first gear by just using the throttle in 1st gear, because it would spin the tyres and try to kill me.

Nowadays....i apply the throttle (full or half or partial throttle - makes no difference) and nothing seems to happen right away...then it just smoothly takes off from the line and then after a half second of moving off, it fully accelerates and does it's thing.



Is this an issue with the transmission, or a throttle/sensor related issue? I suspect my throttle bodies being a problem anyway due to the lack of 'full throttle' power the car has, but seeing as the car is no slower than when i bought it, I'm not sure if they're to blame specifically for this launch issue Im experiencing.

FWIW in the rain it kindaaa spins up from a stop, but tbh it should be nearly impossible to launch in the wet with TRC turned off (it certainly used to be!) so...yeah.

INS1GNIA

I'm not sure if this is the same method in the E class but might as well try.

If you haven't already...

Reset your ECU.
The procedure to reset the ECU is as follows:

1. Turn the ignition key to the "on" position which is just before you crank the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset and you are ready to get new rear tires.

The ECU reset procedure only erases the adaptive transmission and throttle settings. It does not erase any of the fuel, timing or other programming.

Read more: Easiest way to reset my ECU

Also let the car fully warm up, do some spirited driving, then test it out.

Celicasaur

Thanks man. I think...I've tried that before in the past and not noticed any difference, but I'll try it again later on and report back.

chrisridebike8

Unplug the battery overnight to clear any store adaptations. When I installed headers, the car was pulling timing in higher RPMs even with the new tune. Once I reset the adaptations the thing was a beast.

Jasonoff

That's exactly what the steps from INS1GNIA does. The adaptations are stored in the ECU.

chrisridebike8

I was under the impression that was INS1GNIA said was a TCU adaptation reset. And what I said to do was for the ECU. Eurocharged told me to unplug the battery for ECU adaptations. The car felt much more powerful but shifted basically the same as before. Conversely, when I have done the key and throttle reset, the car shifts very differently for awhile (ie-holding revs longer and downshifting earlier). This seems to jive with the fact that TCU can't be flashed with the OBD port and requires its flash.

Jasonoff

The TCU doesn't store the adaptations, it's all in the ECU.

You can also reset adaptations though OBDII.
http://www.mercedesmedic.com/reset-m...-instructions/

MJames2

Thanks for this, I totally forgot how to reset it. For some reason my transmission adapted this retarded down shift that made the car drive like *** probably because i was driving like a grandma and then aggressive then grandma

Celicasaur

Well, I haven't tried a heroic launch yet or tried lighting the tyres, but the car does feel less sluggish now and last night I raced an E46 M3 at the lights in traction sport mode and Sport+ tranny setting....soon as i touched the pedal the car just flew off the line! 0-60 was a total blur....not done a launch like that before in this car. Normally i dab the pedal and there's a really weird split second delay before anything happens and then the car just rolls off the line and then gets moving (and like, it's not traction control stepping in to kerb any wheel spin etc), so last night was a nice surprise.

I'll report back once I've had more of a chance to play with it more.

mr747

But it's your tune it's crap I had the same issue but now mine is fixed torque settings were Over the place

Celicasaur

Who knows bro. Soon as I've confirmed my throttle body openings are as they should be, I'm just going to ship my ecu off to Kleemann.

For what it's worth, I tried the same type of launch again this evening....had that weird delay again. Car does nothing....then suddenly goes, after a slow roll of 1 metre or so.