engine rpm issue

[LiteBulb]

i have this weird prob with rpm. its hard to explain, but i will put a scenario below:assuming that i floored the pedal, the rpm should go smoothly all the way to red line (1k 2k 3k 4k 5k 6k etc.).but what is happening is, the rpm will stall for split secs before climbing like (1k 2k 3k 4k 4k 5k 6k etc.). it doesnt happen only in 4k rpm, but can be in 4.5k or even at 3.5k.it is as if the car climbs till 4k rpm, then rest for few milliseconds before climbing further.any ideas?

 

[seewai]

Sorry bro, I understand what you're trying to say, but not sure what's causing it. Have you sent your car to a workshop for diagnostics yet?

 

[Herbert]

i have this weird prob with rpm. its hard to explain, but i will put a scenario below:

assuming that i floored the pedal, the rpm should go smoothly all the way to red line (1k 2k 3k 4k 5k 6k etc.).

but what is happening is, the rpm will stall for split secs before climbing like (1k 2k 3k 4k 4k 5k 6k etc.). it doesnt happen only in 4k rpm, but can be in 4.5k or even at 3.5k.

it is as if the car climbs till 4k rpm, then rest for few milliseconds before climbing further.

any ideas?

it is call hesitation. most likely vanos/cam shalf problems.

 

[LiteBulb]

Sorry bro, I understand what you're trying to say, but not sure what's causing it. Have you sent your car to a workshop for diagnostics yet?

have not had the time to have it checked. just trying my luck to have it diagnose here and see if i could get an easy fix =)

it is call hesitation. most likely vanos/cam shalf problems.

i googled hesitation, and most of the drivers have idling problem as well. my idling is not a problem, just the rpm climb pause is annoying me. vanos/camshaft sounds like a costly repair..... ouch

i have also read recommendation to upgrade the software. any idea if i could do this upgrade aside from bmw service center? or do you advise if i should do it in the service center?

 

[B33mEr]

Could also be fuel pressure... Have you change your fuel filter?

 

[Herbert]

i googled hesitation, and most of the drivers have idling problem as well. my idling is not a problem, just the rpm climb pause is annoying me. vanos/camshaft sounds like a costly repair..... ouch

i have also read recommendation to upgrade the software. any idea if i could do this upgrade aside from bmw service center? or do you advise if i should do it in the service center?

Symptom of worn out original double vanos seals causing cam shalf out of positions. Replace your vanos seals and mechanic will re-adjust the cam shalf. Also ask mechanic to check cam shalf sensors.

As for update (not upgrade) of ECU software, you can do it at M Speed at USJ for RM 200.00

 

[LiteBulb]

Symptom of worn out original double vanos seals causing cam shalf out of positions. Replace your vanos seals and mechanic will re-adjust the cam shalf. Also ask mechanic to check cam shalf sensors.

As for update (not upgrade) of ECU software, you can do it at M Speed at USJ for RM 200.00

thanks herbert. Albert (WP Auto) will be able to assist in vanos seal replacement right? do i have to get the seals, or will he be able to do it? how long roughly will the replacement takes? i remember you changed yours recently right? rough cost incurred will be?

 

[LiteBulb]

Could also be fuel pressure... Have you change your fuel filter?

hmm. i dont think i did. maybe i should look into this matter as well.

 

[bmw7833]

thanks herbert. Albert (WP Auto) will be able to assist in vanos seal replacement right? do i have to get the seals, or will he be able to do it? how long roughly will the replacement takes? i remember you changed yours recently right? rough cost incurred will be?

Let me know if u need the vanos seal, i have some extra.

 

[eujinee]

i've the same issue....it occurs once in a blue moon......

sometimes rev...until 3-4k rpm....suddenly can feel the car hesitate to move..even paddle to the floor..the rev still remain around tht rpm range....thn sometimes got idling problem....wen crank up the car, it started thn died off right away..even wen moving and low speed it still died off....only choice i've is input slightly on the acelerator paddle and left foot brake..and jalan...

got this issue 1 year ago...still occurs once a while..

isit the cam problem or just fuel filter or spark plugs..?? my engine is m43tub19...

 

[LiteBulb]

i've the same issue....it occurs once in a blue moon......

sometimes rev...until 3-4k rpm....suddenly can feel the car hesitate to move..even paddle to the floor..the rev still remain around tht rpm range....thn sometimes got idling problem....wen crank up the car, it started thn died off right away..even wen moving and low speed it still died off....only choice i've is input slightly on the acelerator paddle and left foot brake..and jalan...

got this issue 1 year ago...still occurs once a while..

isit the cam problem or just fuel filter or spark plugs..?? my engine is m43tub19...

i had this prob with my previous car, MAF sensor was faulty.

 

[eujinee]

that is expensive..............................

 

[B33mEr]

that is expensive..............................

It depends actually ... could be the heating element in the MAF is dirty just clean it with CRC MAF cleaner and see how it goes ... May just save you $$$
CRC MAF cleaner cost around RM30-40

 

[eujinee]

It depends actually ... could be the heating element in the MAF is dirty just clean it with CRC MAF cleaner and see how it goes ... May just save you $$$
CRC MAF cleaner cost around RM30-40

yah..thanks bro....will try tht...aaaaaaaaaaa..haven clean before. i saw a thread here on how to clean...from jarance...i will work my way up...

 

[LiteBulb]

sent my car in for a checkup. explained my issues to the mech. he said he has not come across such issue before. plugged in the diagnostic machine, no error code noted. hence, had him to changed the spark plugs.

no miracles, but puzzled.

 

[Herbert]

sent my car in for a checkup. explained my issues to the mech. he said he has not come across such issue before. plugged in the diagnostic machine, no error code noted. hence, had him to changed the spark plugs.

no miracles, but puzzled.

So problem resolved by replacing new spark plugs, right?

 

[LiteBulb]

nope. still not solved. was hoping that the plugs would solve it, but nope.

 

[LiteBulb]

updates:

i noticed that when i have the gas pedal fully depressed, sometimes, when i lift the pedal abit, rpm will suddenly surge 1k higher.

say rpm is now at 4k, when i release pedal abit, it will shoot up to 4.5k/5k rpm.

 

[QD250]

try the cuci carbon method daily and see whether it helps or not...