E90 Engine Start Problem

[devild76]

Hi Sifus,

Wonder if you can help me out a little. Recently I have a little problem while starting my engine. Once I push the start button it will crank for 2-3 sec before the engine come alive. And when it does, the yellow engine management light comes on. I switch off the engine and restart and it starts as normal again. This only happens maybe once a week. Lately, my engine stalls at the traffic lights, but that happens maybe once in 2 weeks.

Can anyone please help to advise if it's my battery problem? My car is the E90 320i year 2008 which I bought 2 years ago. For all I know the batt hadn't been changed since then. However if it's the battery problem, I though I will not be able to start the car at all? Or it would be difficult to start most of the time? not once in a while?

Awaiting advise. Thanks

Regards

D

 

[Mavik]

It could be signs of the battery but there may be other factors as well. Best to go have it checked by one of the BMW shops outside. Run a full check to see if there are any error codes thrown.

 

[cg]

How young is the battery ? The sign looks like a battery going bad.... Go and check the battery condition..... The year of the battery being manufactured is on the battery terminal if original bmw battery....

 

[anaksarawak]

Another possibility is blown head gasket which is a known /common issue with N46B20 engine. Open your engine oil cap to see if your engine oil is clear? And check your coolant level.

 

[devild76]

Hi AnakSarawak,

Engine oil seems reasonably clear (I've just got a service about 2 weeks ago)... coolant level ok (again just serviced) however I find that I need to top up my coolant every month with 1 can of coolant. I always think that it's the BMW engine which can be very hot that's depleting the coolant level. Please help to educate me otherwise. Is there any other sign from a blown head gasket?

My battery is the BMW ori and I will try to check it out tomorrow to see if I can get the year manufactured as suggested by CG.

 

[devild76]

Hi All,

BTW, can anyone suggest what is the size of my battery? I've got the car to the workshop and they tell me I should be using a DIN88 while in the many many post in this forum by Astroboy, he is saying DIN100.... so 88 or 100? Please advise. Thanks

 

[gimli]

din66,din88 or din100 can be used without any problems. I find din100 to be a bit of a tight fit. quite difficult to install.

 

[anaksarawak]

Hi AnakSarawak,

Engine oil seems reasonably clear (I've just got a service about 2 weeks ago)... coolant level ok (again just serviced) however I find that I need to top up my coolant every month with 1 can of coolant. I always think that it's the BMW engine which can be very hot that's depleting the coolant level. Please help to educate me otherwise. Is there any other sign from a blown head gasket?

My battery is the BMW ori and I will try to check it out tomorrow to see if I can get the year manufactured as suggested by CG.

Oh no!!!! coolant loss is the sign of blown gasket bro. Soon you need a top overhaul and valveseals replacement. Please go to an experienced workshop so they to skim your engine head with machine not hand and sandpaper.

DIN88 is ok bro.. Century or GP or Yokohama cukup la and they are much cheaper vs BMW ori

 

[devild76]

Oh no!!!! coolant loss is the sign of blown gasket bro. Soon you need a top overhaul and valveseals replacement. Please go to an experienced workshop so they to skim your engine head with machine not hand and sandpaper.

DIN88 is ok bro.. Century or GP or Yokohama cukup la and they are much cheaper vs BMW ori

Oh Nooooo x 10000.... any idea how much it cost to have my engine head skimmed? This'll set me a benchmark when I go to the workshop to nego with them.. Many thanks in advance

 

[bmwjackiee36]

Check for any physical leak before jump to conclusion of blown head gasket...

 

[kolamp]

My coolant only needs to top up around 3-4 months time even that is just a small amount...a bottle of coolant a month is not normal...probably what anaksarawak said is true

 

[anaksarawak]

N46B20 engine is super fragile and my suggestions are pure guess based on personal experience. By the way, please make sure the topoverhaul is done by professional and honest workshop. If not you will have to change the whole engine should they damaged your lower block. Price is around RM1500-2500 depending on items need to be replaced.

Normally they are
1. Top Overhaul Kit (gaskets and lots of orings including valves seal)
2. Engine oil cooler
3. Engine cover gasket
4. Engine oil and filter

p.s. Do ask for ori triple layer engine gasket

Good luck bro

 

[devild76]

Hi All,

Just an update, Changed by battery to Panasonic DIN100... and it''s a perfect fit from the ori BMW. I changed it together with the workshop fellow (i'm a little of a DIY guy) and together we took almost 1.5 hours to do it.... man.... not easy as it's like i said perfect fit without much room to move. Have to thank youtube for instruction tho. Workshop fella also checked but no physical leak from the engine... so as to his advise... keep fingers cross and hope. At the moment... everything is back to normal... push start, one crank and engine roar to life. Notice a little smoother change in gears as well as more power going uphill.... but then again could be my imagination

Now sit back and pray

 

[devild76]

Awww..... problem persist... now engine dies sometimes at the traffic lights as well as going up a steep hill. Look like it will need to stay at the hospital for a few days for a complete scan. Will insist for them to open up and check if it's a blown gasket. Suggestion of any cheap and honest workshop anywhere in KL?

 

[anaksarawak]

Awww..... problem persist... now engine dies sometimes at the traffic lights as well as going up a steep hill. Look like it will need to stay at the hospital for a few days for a complete scan. Will insist for them to open up and check if it's a blown gasket. Suggestion of any cheap and honest workshop anywhere in KL?

So sorry to hear about your car bro... I don't have anyone to recommend, it's not easy to find a good one today. My car is in Johor today pending transport of a recon engine to be transported down to JB. Suspect is due to poor workmanship of my top overhaul job done earlier.

 

[devild76]

Hi All,

Just an update on my car. I've got a contact from my bro in law for Berlin Motor Works... in segambut. Went there, plug in computer to the OBC... voila... it's the crankshaft sensor. The owner (Ah Keong) was trying to explain the crankshaft sensor controls alot of things and how it works... I was like... right..... please fix it. Total time needed was 3-4 hours as the position of this sensor is way under the engine and difficult to access.

Just a note at the side, during the installation by Ah Keong's workers, I see Ah Keong glued his face to the computer trying to study the electrical diagram for X3. I inquired what he was doing and he told me he's got a client with a faulty auto window.. and he's testing the wiring one by one. Wow... well for me... a mechanic who bothers to go to the length to study the wiring schematic and did not ask you to change the entire module is a thumbs up.... then again this is my humble opinion.

Anyway back to the car... got the car back just under 3 hours. Now everything is fine... gear shift smoother (not imagination.. it's like driving a CVT), more power (due to the responsive gear shift), even the occasional little jerk when i shift down a gear is GONE.... wow... it's fun to drive it again.. lol

So... anyone having my symptom to your car (ie, difficult to start, loss of power, engine dies for no reason)... it might be the crankshaft sensor. But should take the advise of all sifus here to have a comp plug in to know for sure.