E30 M40 cold start problems

[kelvinp]

Guys need your advise here, My car (M40B18) engine dies after erratic idling everytime it gets started when its cold. Everything goes fine after driving it for 2 minutes. What could be the problem? Is there a cold start sensor for this car? or is the ICV the culprit? or maybe the AFM? Thanks in advance!

 

[pakupakis]

Hi,

My E30 has that problem too. Especially after rain, and overnight, the car is kinda jerky and heavy, takes some time before it gets back to normal.

But when the weather is hot, no rain, the car is better.. not so jerky.

Dunno why le...

 

[ersalle]

No cold start sensor for E30 M40B18, try clean the ICV 1st. Or might be one of the spark plug is wet.

 

[eau-rouge]

ur spark plug may cause the problem

 

[kelvinp]

thanks for the replies guys,

ICV has been cleaned couple of times but problem persist. Does the ICV really might be the culprit? but it idles excellently once the car is driven for a couple of minutes.

well the spark plugs are kinda new, got it changed together with the distributor cap n cables about 6 months ago.

Anyway, if the spark plugs are wet, what are the symptoms?

 

[DiNAN.328i]

maybe it's time to adjust the timing on the cams... did it once before and it worked out really well.

 

[kelvinp]

any other symptoms? where are the sifus?

 

[said]

Hi
Previously, I also face that problem, suddenly i have engine cold idling problem, until one fine day, my car battery kaput.
Changed new battery... walauwehhhhh... everything goes back to normal.. no problem... dunno larr..maybe my luck. now..early morning ker, after rain ker..easy to start and very good idling.

said

 

[kelvinp]

Hi
Previously, I also face that problem, suddenly i have engine cold idling problem, until one fine day, my car battery kaput.
Changed new battery... walauwehhhhh... everything goes back to normal.. no problem... dunno larr..maybe my luck. now..early morning ker, after rain ker..easy to start and very good idling.

said

serious shit dude! guess what?? my battery also today started kaputting... all lights on meter/buttons/interrior goes off when cranking to start the engine..had to crank twice.. gonna get the battery changed tomoro.. will update soon.

 

[ersalle]

HEHHEEH symptoms of a failing battery.......learn something new now ehheheh

 

[pussy]

hmmn.. fireblade also has this problem on his e30evo..

 

[Fireblade]

hmmn.. fireblade also has this problem on his e30evo..

Well mine does struggle to move when cold. I've changed the AFM(used one), cleaned ICV, temperature sensor - helps a little but doesnt solve the problem. Even swapped another ECU but no difference. I have reset the throttle butterfly & switch so that the idling is higher at 950rpm and this has helped. BTW, my battery is quite new.

Dinan.328i - how did you reset your cams? This is one thing I havent checked.

 

[kelvinp]

well, i've changed the battery and now the engine doesn't dies off like before during cold start, but erratic idling still exist when engine is cold.

Ultimately, i've noticed white smoke comin out of exhaust during cold starts. Checked the spark plugs and all looks fine, no wet ones.

any suggestions?

 

[ersalle]

White smoke during cold start.....oh oh hehehe head gasket gone already

 

[pussy]

White smoke during cold start.....oh oh hehehe head gasket gone already

ersalle, i beg to differ, white smoke during start up's are valve seals leaking..

 

[ersalle]

Blue smoke would be valve seals leaking, plus u can even smell engine oil burning at your exhaust. During cold start if the exhaust got white smoke for more than 10mins plus traces of water droplets at exhaust tip,can even smell coolant but do confirm checking the engine oil at the oil filler cap(water vapour) and dip stick(to see engine oil creamy)