Question about ECU + weird rattling noise

[silencer51]

My car's ECU has been flashed once with firmware version 7.73.

Apparently Sagem ECU's can only be flashed once, afterwards they become 'locked' and cannot be upgraded again.

I was wondering if there is any way to bypass this and update my ECU to the newest firmware.

Does anyone have any ideas?

Also, when accelerating in 2nd gear and up I can hear a sort of rattling noise mixed with normal engine noise, up until about 3-3,5k rpm (engine noise then becomes more pronounced drowning out any other noises).

This is only noticeable when driving with open windows around town.

The noise reminds me of pinging and also of the classic '8valve sound' produced by 8-valve engines under acceleration.

I've ruled out pinging since this has been going on for 2 years or more (the engine would be destroyed by now), and also since then I have had a lot of things replaced/improved (such as spark plugs, dephaser pulley and related belts etc.) and I use 100 octane high quality fuel. No difference in the noise whatsoever. Also from what I understand pinging is noticeable even from within the cabin.

This only happens when the engine is under load, when revving while stationary and out of gear everything sounds great.

Also sometimes its more pronounced and other times less so.

It sounds like something is loose and rattles when the engine is under load.

Imagine a tin box filled with small pieces of metal vibrating being shaken around very, very fast.

Could it be something in the gearbox? A rattling bearing or something? Or perhaps a crack in the exhaust manifold? I'm almost sure that sometimes, when changing gear while cruising, if I release the clutch pedal clumsily I can hear the same sound as the transmission moves slightly on its mounts.

I have had every mount except the top left one replaced recently, made no difference also.

I will try and record a sample and upload it.

[silencer51]

Can anyone confirm whether the ECU locking thing is true or not? WebCode?

[WebCode]

No the ECU does not lock.. It can be programmed by CLIP multiple times..

[silencer51]

No the ECU does not lock.. It can be programmed by CLIP multiple times..

Thanks for clarifying that WebCode!

What could then be the cause of the error that kept coming up when I was at my dealer and we were trying to update the ECU using the latest CLIP and the latest update disc?

The weird thing is that I have heard this from other M2 owners here in Greece, their dealers have also told them that they can only update the ECU once...

WebCode, what is the latest version of the injection software for the K4M-760/1 engine? (model type BM0C)

[silencer51]

Also, any opinions on the rattling noise?

[silencer51]

Today me and the mechanic at the dealer tried for well over an hour to reprogram the injection computer (update to the latest version) to no avail.

Every time that goddamned "ECU has already been reprogrammed once, reprogramming aborted" message kept popping up.

We even tried to 'fool' the CLIP into thinking the car was part of a recall campaign (which should theoretically override the lockdown). That didn't work either.

I don't understand this - different countries have different restrictions on reprogramming?

WebCode says you can update the ECU as many times as you want provided you flash a newer version of the firmware and not the existing one.

Apparently this is not possible in Greece...


So I'm guessing the only solution would be to take the ECU to a professional chiptuner and flash it with a custom firmware (I really hope that can be done).

Shame on Renault and shame on the pea-size brained idiot who came up with this stupid lockdown thing (apparently other car makers have a restrictions on the times an ECU can be reflashed but Renault is the only one where you can do it only once)....