e30m40 high idling engine

[selespeed]

hi guys; here's a very annoying problem resulting in high fuel consumption. when i turn on the to start the engine cold or warm, the engine rpm shows liek 1500 to 2000. pressing the pedal will revv up to make it worse but it wont want to return to the proper idle of 800-900 rpm. in fact, it is very RELUCTANT. pressing the pedal actually makes it worse! when i stop the car at traffic lights, the engine would revv to like 1800 rpm and engine sound is loud. this makes heads turn but the unwanted attention is embarassing. i tried to play with the area where the cable is connected. but this doesnt help. like using my finger to push it back but doing so would make the idle extremely low and the idle becomes erratic and hunts up and down and eventually engine dies. what is the cause of this problem? fyi, the icv has been cleaned before. advice please how to solve the problem!

 

[evilnickwong]

It still sounds like the ICV, maybe it's dirty again or just plain not working.
Otherwise, check for vacuum leaks and also make sure AFM flap is still moving smoothly.

 

[chriseunos]

can check the throttle position switch and see

 

[selespeed]

It still sounds like the ICV, maybe it's dirty again or just plain not working.
Otherwise, check for vacuum leaks and also make sure AFM flap is still moving smoothly.

the ICV problem is unlikely. when it's cleaned some 4 months ago, it didnt really fix the problem. vaccum leaks but where is the probable leak?

AFM flap? can this be serviced? what about this thing called TPS? what is the function huh?

 

[selespeed]

can check the throttle position switch and see

aha, i wrote this not knowing you also mentioned it. TPS i chanegd this many years ago and could not recall why. so tps faulty? or can it be cleaned?

 

[selespeed]

can check the throttle position switch and see

TPS - seems like it? http://www.youtube.com/watch?v=tK80iBgjFyg

 

[ICEMAN 68]

maybe worn out cam lobes too can cause such problem .....

 

[selespeed]

maybe worn out cam lobes too can cause such problem .....

thanks iceman for the info.

feb 2006, 215,600km: new camshaft, new valves, new rocker arms etc due to broken belt tooths.
march 2008, 300,000km: another top overhaul and new camshaft!

as you can see. this is my second camshaft.
it is now 38k km later. the m40 camshaft is bad but could it be worn out so easily so soon? of course in between the two repairs i have the belts and associaed stuff replaced.

anyway, can worn cam lobes cause high idling speed?

 

[ICEMAN 68]

thanks iceman for the info.

feb 2006, 215,600km: new camshaft, new valves, new rocker arms etc due to broken belt tooths.
march 2008, 300,000km: another top overhaul and new camshaft!

as you can see. this is my second camshaft.
it is now 38k km later. the m40 camshaft is bad but could it be worn out so easily so soon? of course in between the two repairs i have the belts and associaed stuff replaced.

anyway, can worn cam lobes cause high idling speed?

yes it could ...the last new cam shaft of mine lasted only around 10K miles clocked till the tak tak tak lifters sound starts to appear once more again ....do note that i change my engine oil every 45 days and yet it still makes such noise ....

before the lifter noise came, the car was so balanced and never had such idling problem , but as it ages the problem start to appear once more again occasioanlly ...after a hard drive if come instantly ...

i've done all those ICV , AFM , hoses , plug cables etc etc etc ..and infact almost everything ....till i made up my mind to give my M40 a rest for once .... as the amount payed for such items to be done is the same as playing with an M50 ...

 

[chili e30]

wire harness might cause this problem also.

 

[ICEMAN 68]

wire harness might cause this problem also.

ha ha ha my wire harness just gave out FREE to the surat khabar lama , besi buruk person ... FOC

 

[selespeed]

problem solved!

just when i decided to change all the rubber hoses to isolate the problem, the mechanic has solved it, seemingly his midas touch!

he said it si due to a bad or worn throttle body that does not rteturn to proper idle position (the metal part). and checked that hoses are confirmed not leaking.

now that the idle returns to normal between 900 to 1000.

so far so good and let's see my next engine start cold or warm if the fix is permanent.

thank you all guys for your inputs. i appreciate all of you.

 

[chili e30]

ha ha ha my wire harness just gave out FREE to the surat khabar lama , besi buruk person ... FOC

aiyo yo...if need this item is very hard to get leh...

 

[evilnickwong]

good to hear you've got a probable fix to the problem.
so was the TB flap not returning because it was just dirty or did he replace the whole unit?

 

[selespeed]

good to hear you've got a probable fix to the problem.
so was the TB flap not returning because it was just dirty or did he replace the whole unit?

it's slightly worn and not returning to home position properly. has anyone of you used a stronger spring? i have to examine closely how that flap looks like or perhaps can weld the worn part and then sand it to good fit? just some wild guess! i am not technical

 

[ICEMAN 68]

aiyo yo...if need this item is very hard to get leh...

yes indeed , but when you have it , none would want it ...he he he ...infact many of my left over M40 parts was sold to some besi buruk fellow and i got a good price for it ....

SS glad that you problem is solved

 

[chili e30]

yes indeed , but when you have it , none would want it ...he he he ...infact many of my left over M40 parts was sold to some besi buruk fellow and i got a good price for it ....

SS glad that you problem is solved

aiya...should give it to me i can keep for you....hehe...

 

[ejat shafiq]

me got the prob when i'm on long journey. whenever stop,it can reach 2000 rpm, and it is really, really annoy me.