C34 S1 Manual, Revs When Stopping?

[nicksamaniac]

Hi all, since converting my s1 to a manual I've loved it, but for some reason- now this is very intermittently happening -it revs up to about 1500, sometimes up to 2000rpm when coming to a stop or very slow turn.

This is very frustrating when trying to slow down for a turn or roundabout, and stay in 3rd gear -but it's pushing like a dozer!

or you slowly pull up at the lights and it's pulling 2000rpm (and it's reasonably loud) and people are looking like what's this dude doing?

I've not been able to replicate the conditions or driving techniques to make it do this, it's very random.

Some days it will do it at every stop or slow turn/intersection.

Other days it won't do it at all the whole drive?

Sometimes it goes between this revving state and idle repeatedly while stopping (revving up and down every 1-2 secs)

I can only assume it has something to do with the auto tune?

Maybe it's revving slightly to maintain converter speed/pressure? (because it doesn't know any better).

The only auto mod I did was bridge the neutral switch in the engine bay so it can start.

Is there something I can do to the input signals to the ecu? Vehicle Speed sensor or something to fool it?

Any help on this would be great? As its starting to p!ss me off!

[nicksamaniac]

Forgot to mention, it stops revving as soon as the car has all but come to a complete stop, say under 1-2km/hr it will drop back to idle.

[Dan_J]

is the plug for the clutch pedal connected?

[nicksamaniac]

There is a switch on the pedal, but what can I plug that into? Seeing as it was an auto.

Can you expand on that?

[nicksamaniac]

Do any of the gun tuners know if this is tune related or is it an input that causes this?

I'll prob end up fitting a pfc eventually.

[nicksamaniac]

Bump, still have this going on.

[DaveB]

Sorry that I can't offer anything useful, other than to say what you probably already know: my auto does that, and I assume it's normal for the auto ECU. If you rev it in neutral even, after the revs fall, they will "blip" back up to about 1,500-2,000 rpm for an instant. I think it's part of the auto ECU setup. Seems to me that this is more than just tune - that there are extra "smarts" in the auto ECUs which are responsible for this.

[nicksamaniac]

Ok, next question, does anyone know where to source an r33 style ecu plug?

I have a stock manual tune gtst r33 ecu here. Ill just re-pin the plug to use it.

Or-

Is the s1 c34 ecu nistune-able?

Or can I use a r34 neo power fc?

Im so over this issue I'm just going to buy an ecu with a manual tune!