ECU Malfunction

[krsna86]

Dear all,My cylinder 6 recently was misfiring. After changing plugs and coils, the problem still precists. Mech's dignostics is the ecu malfunction causing injectors not injecting fuel consistently. Ok here is the bomb. New ECU. RM7k ( Out of topic), 2nd hand RM3.5k ( with programming and 6 months warranty), 2nd hand RM2.8K ( With programming and 1 month warranty), repair current ecu RM2k ( no warranty).What should i do guys? New is out of reach...are the prices resonable? Really confused, please help me.....Advanced thanks to all...

 

[wingzee]

Hi krsna86, have you seek second opinion on the issue? There have been cases of faulty ECU albeit they are pretty rare.

How did your mechanic came to the conclusion that the ECU is faulty? Did the computer diagnosis throw out any fault codes?

 

[Strider74]

Hi krsna86,
I tend to agree with wingzee on this...get a second opinion.

 

[krsna86]

Hi krsna86, have you seek second opinion on the issue? There have been cases of faulty ECU albeit they are pretty rare.

How did your mechanic came to the conclusion that the ECU is faulty? Did the computer diagnosis throw out any fault codes?

Have not seeked a 2nd opinion as JB does not have very trustworthy mech who are not looking to drink your blood.

He came to the conclution after changing the spark plug and ignition coil for the faulty cylinder. Misfiring is not constant take means it happends then when we clear the fault code it goes back to normal. So he concluded it must be electrical not mechanical.

Do you have any other opinion on this matter bro? Appreciate your advice.

 

[Mtigo]

Start with easy stuff first than think about your faulty ECU

1) Check main air tube leading from MAF to throttle body and ICV, the little elbow will often crack with age and let air get in, causing your issue. also not forget check all your vacuum lines as well as your PCV valve, as it seems to be the one of the causes of our e46's mis-firing. (the escaped air causes the o2 sensors to get faulty readings, causing the engine to misfire due to the inaccurate reading.)

2) Fuel delivery "could" be an issue. Try replaced fuel filter.

3) Cam sensor.

Good luck!

 

[tweiboon]

Have not seeked a 2nd opinion as JB does not have very trustworthy mech who are not looking to drink your blood.

He came to the conclution after changing the spark plug and ignition coil for the faulty cylinder. Misfiring is not constant take means it happends then when we clear the fault code it goes back to normal. So he concluded it must be electrical not mechanical.

Do you have any other opinion on this matter bro? Appreciate your advice.

U can buy ECU from chop shop or ebay or any online website. After that look for someone which can pair the ECU with you EWS so that you can start your engine by using your key.
from ebay eg-->http://www.ebay.com/itm/01-BMW-E46-...Parts_Accessories&hash=item2a2d31e654&vxp=mtr
As you can see get this ECU is super cheap in ebay or online website.

Pair the ECU and EWS cost around RM300 and you can count the total cost now.

 

[wingzee]

Have not seeked a 2nd opinion as JB does not have very trustworthy mech who are not looking to drink your blood.

He came to the conclution after changing the spark plug and ignition coil for the faulty cylinder. Misfiring is not constant take means it happends then when we clear the fault code it goes back to normal. So he concluded it must be electrical not mechanical.

Do you have any other opinion on this matter bro? Appreciate your advice.

Do a computer diagnostic & see what fault codes that were generated. Root cause might be determined by looking at the codes.

I used to have a constant misfiring on a particular cylinder. And still happens after replacement of new coil. Once error cleared, misfiring will cease but will come back later on. Only upon replacement of second new coil that it solves the problem. This meant that even new coil might not be performing up to its optimum.

What's your milleage by the way?

Learnt this from a fellow forummer, always try solving the issue via the cheapest option first.

 

[EEEE30]

Dear all,

My cylinder 6 recently was misfiring. After changing plugs and coils, the problem still precists. Mech's dignostics is the ecu malfunction causing injectors not injecting fuel consistently.

Ok here is the bomb. New ECU. RM7k ( Out of topic), 2nd hand RM3.5k ( with programming and 6 months warranty), 2nd hand RM2.8K ( With programming and 1 month warranty), repair current ecu RM2k ( no warranty).

What should i do guys? New is out of reach...are the prices resonable?

Really confused, please help me.....

Advanced thanks to all...

Welcome to the world of electronics.
There should be a sticker on your ECU which indicates the brand and ECU number. You can refer to this combination of info when you check the prices. Siemens and Bosh makes them for BMW.
Ebay/bmw forums (e46fanatics) is your friend. There you can get a used ECU for much much less.

 

[krsna86]

Start with easy stuff first than think about your faulty ECU

1) Check main air tube leading from MAF to throttle body and ICV, the little elbow will often crack with age and let air get in, causing your issue. also not forget check all your vacuum lines as well as your PCV valve, as it seems to be the one of the causes of our e46's mis-firing. (the escaped air causes the o2 sensors to get faulty readings, causing the engine to misfire due to the inaccurate reading.)

2) Fuel delivery "could" be an issue. Try replaced fuel filter.

3) Cam sensor.

Good luck!

Thanks bro, will show this to my mech. Appreciate it.

 

[krsna86]

U can buy ECU from chop shop or ebay or any online website. After that look for someone which can pair the ECU with you EWS so that you can start your engine by using your key.
from ebay eg-->http://www.ebay.com/itm/01-BMW-E46-...Parts_Accessories&hash=item2a2d31e654&vxp=mtr
As you can see get this ECU is super cheap in ebay or online website.

Pair the ECU and EWS cost around RM300 and you can count the total cost now.

RM300, wow.. they quoting me around RM1k+ to reprogram the ECU...damn...

 

[krsna86]

Do a computer diagnostic & see what fault codes that were generated. Root cause might be determined by looking at the codes.

I used to have a constant misfiring on a particular cylinder. And still happens after replacement of new coil. Once error cleared, misfiring will cease but will come back later on. Only upon replacement of second new coil that it solves the problem. This meant that even new coil might not be performing up to its optimum.

What's your milleage by the way?

Learnt this from a fellow forummer, always try solving the issue via the cheapest option first.

Even after clearing the fault code my firing order will be like this

0.50+-
0.50+-
0.50+-
0.50+-
0.50+-
3.20+-
This is at idle.

My mileadge is around 250k now, bought my car at around 220k....plug and coil are brand new for all 6 cylinders

 

[krsna86]

Welcome to the world of electronics.
There should be a sticker on your ECU which indicates the brand and ECU number. You can refer to this combination of info when you check the prices. Siemens and Bosh makes them for BMW.
Ebay/bmw forums (e46fanatics) is your friend. There you can get a used ECU for much much less.

Thanks bro.. will check online now...

 

[wingzee]

Even after clearing the fault code my firing order will be like this

0.50+-
0.50+-
0.50+-
0.50+-
0.50+-
3.20+-
This is at idle.

My mileadge is around 250k now, bought my car at around 220k....plug and coil are brand new for all 6 cylinders

Before you cleared all the fault codes, what are faults shown? I presume the above readings came from GT1 and values shown are voltage generated to each firing coil. Swap coil from say #6 to #5 and see any difference?

 

[krsna86]

Before you cleared all the fault codes, what are faults shown? I presume the above readings came from GT1 and values shown are voltage generated to each firing coil. Swap coil from say #6 to #5 and see any difference?

The fault code was-Misfiring Cylinder 6. Did a few times swapping bro.. all to no avail..

 

[wingzee]

The fault code was-Misfiring Cylinder 6. Did a few times swapping bro.. all to no avail..

Okay prolly try to loan an ECU first prior to purchasing it just to double-confirm. Visit a kind halfcut shop and pay them some deposit. Some in KL ones are kind enough to do so.

 

[krsna86]

Okay prolly try to loan an ECU first prior to purchasing it just to double-confirm. Visit a kind halfcut shop and pay them some deposit. Some in KL ones are kind enough to do so.

Thanks bro,

Managed to get a ECU to test first. Will update the outcome..