Does the ECU give false alarms?

[Wh0cArEs]

Hi,

I experienced this a couple of days back...

i floored the accelerator hard for a sec and suddenly this error came up on the i-drive:

Engine fault. Power will be reduced but journey can proceed blah blah blah

Strange thing is, i switched the engine on and off when I came to a red light and the error msg was gone. The car also behaved normally after that. I've not seen the error msg again since.

Anyone experienced something like this b4?

 

[wt_know]

Re: Does the ECU give false alarms?

limp mode ?

 

[Wh0cArEs]

Re: Does the ECU give false alarms?

limp mode ?

yea... it went into limp mode

 

[Jason8822]

Re: Does the ECU give false alarms?

did you install sprint booster or something like that recently?
read some thread about this issues

 

[ktnpl]

Re: Does the ECU give false alarms?

I got the message "Engine fault! Reduced Power" on my i-Drive recently. Sending my car to PML on Monday.

I saw a few threads on this issue. The cranking time is longer than normal and the engine vibrates during start and high speed. It is most likely due to high pressure fuel pump failure which is common for the N54 engine. My car is about 1 and a half years old. Mileage 12,000km.

Is yours an N54 engine too?

 

[satinGHOST|r!der]

Re: Does the ECU give false alarms?

Happens sometimes even on stock cars. Issue of the ECU miscalculating the boost target threshold. On tuned ECU's, might happen more if boost level is too high. These errors more predominant during hot weather.

 

[Wh0cArEs]

Re: Does the ECU give false alarms?

did you install sprint booster or something like that recently?
read some thread about this issues

I'm using the Juice Box... it's been >1mth and 1st time this has happened.

 

[Wh0cArEs]

Re: Does the ECU give false alarms?

I got the message "Engine fault! Reduced Power" on my i-Drive recently. Sending my car to PML on Monday.

I saw a few threads on this issue. The cranking time is longer than normal and the engine vibrates during start and high speed. It is most likely due to high pressure fuel pump failure which is common for the N54 engine. My car is about 1 and a half years old. Mileage 12,000km.

Is yours an N54 engine too?

Yeah... driving a E90 335i. My cranking is fine. There were some engine vibration issues at idle recently but that was rectified when I changed my spark plugs.

Let me know what PML says abt your car since we got the same error msg.

 

[Wh0cArEs]

Re: Does the ECU give false alarms?

Happens sometimes even on stock cars. Issue of the ECU miscalculating the boost target threshold. On tuned ECU's, might happen more if boost level is too high. These errors more predominant during hot weather.

Tks for the info.

But does this mean there's nothing to worry abt since the error msg went away after i restarted the engine and the car is behaving normally now?

 

[ktnpl]

Re: Does the ECU give false alarms?

Yeah... driving a E90 335i. My cranking is fine. There were some engine vibration issues at idle recently but that was rectified when I changed my spark plugs.

Let me know what PML says abt your car since we got the same error msg.

I brought my car to PML Alexandra this morning. They will take 2 days to diagnose and remedy it.

Their loan cars have to wait so I just settle for their alternative offer of 4 taxi vouchers (2 for each day).

I also included some minor bodywork and grooming so I will only get back the car on Friday or Saturday.

 

[Wh0cArEs]

Re: Does the ECU give false alarms?

I bought my car to PML Alexandra this morning. They will take 2 days to diagnose and remedy it.

Their loan cars have to wait so I just settle for their alternative offer of 4 taxi vouchers (2 for each day).

I also included some minor bodywork and grooming so I will only get back the car on Friday or Saturday.

tks for the update! let us know what the final diagnosis is

 

[lalilulelo]

Re: Does the ECU give false alarms?

I have experience with the car losing power and going into limp mode as well, but it only lasted less than 3 seconds and everything was back to normal after that. there was a fault warning light on the driver console, but Idrive did not show anything, and the icon disappeared as soon as the engine is back to normal.

this happened when my car was less than 1000km old, twice, now my car is approaching 1 year old and the problem never surfaced again.

My Idrive has gone nuts on several occasions, it once prompted transmission fault when I start the engine, restart it and the warning was gone, checked control, and it showed no fault, brought it to PML and they said everything seems OK

 

[Markus]

Re: Does the ECU give false alarms?

Yep read in US forums that it has to do with fuel pump. Common with the 335s apparently - just got to live wid it but can be very irritating...

 

[ktnpl]

Re: Does the ECU give false alarms?

tks for the update! let us know what the final diagnosis is

PML has replaced the HPFP plus some software update. Car sounds quieter and feels smoother now compared to just before the repair . It took 3 days including replacement of faulty light indicator and brake fluid.

The showroom section is very quiet (same situation for other marques) but the servicing section is busy.

 

[Jason.Neo]

Re: Does the ECU give false alarms?

Not sure why it happens to Turbo Bimmers... but from my previous experience tuning Turbo Subarus, This problem is common with those cars. Be it WRX or STi or Forrestors... Especially JDM ones.

This is due to the ECU's stock maping for errors and emergency. What i did back them was to flash tune the ECU and push the limiters up by a notch or two depending on driver and boost... These were due to a number of factors for those cars namely, Weather and air tempt, and Fuel Octane. Another way those Subbys prevent this is to use only High Octane Fuel or Use Octane boosters when they are up north...

Hope my slightly related explaination helps...

And i do not rule out problems with the HPFP not providing enough fuel too...