RM European Auto Parts
Results 1 to 7 of 7

Thread: 08 bmw 318i can't start when engine warm.

  1. #1
    Join Date
    Apr 2018
    Location
    Hartlepool
    Posts
    3
    My Cars
    2008 Bmw 318i E91

    08 bmw 318i can't start when engine warm.

    Hello everyone,i am having a hot start issue and have run out of ideas,the car doen't help me either,cause check engine light doesn't come on and no codes come up.
    It goes like this:
    At some point my car started to go into limp mode and misfiring,i changed spark plugs,didn't help,changed injectors,didn't help much,then one of ignition coils went visibly bad-it burned a hole in it,so i changed all the ignition coils for aftermarket ones,turns out it was ignition coil all along,as car now runs fine.But a week later i went somewhere,stopped the engine,tried to start 5 minutes later,and it won't. The starter tries to start it,speedo shows like 300-500 rpm,but it doesn't actually start.If i wait 20-30 minutes it starts instantly,and it starts first time everytime on any other occasion,just not when you have driven for a while and stopped the engine.I was thinking fuel pump,but in that case wouldn't the car stutter or shake and misfire?
    Or could it be those aftermarket coils? Or something else? As i said,i've run out of ideas.
    Thanks for any help in advance

  2. #2
    Join Date
    Jul 2013
    Location
    Casablanca, Morocco
    Posts
    780
    My Cars
    2001 e46 323i
    Quote Originally Posted by diselpowa86 View Post
    Hello everyone,i am having a hot start issue and have run out of ideas,the car doen't help me either,cause check engine light doesn't come on and no codes come up.
    It goes like this:
    At some point my car started to go into limp mode and misfiring,i changed spark plugs,didn't help,changed injectors,didn't help much,then one of ignition coils went visibly bad-it burned a hole in it,so i changed all the ignition coils for aftermarket ones,turns out it was ignition coil all along,as car now runs fine.But a week later i went somewhere,stopped the engine,tried to start 5 minutes later,and it won't. The starter tries to start it,speedo shows like 300-500 rpm,but it doesn't actually start.If i wait 20-30 minutes it starts instantly,and it starts first time everytime on any other occasion,just not when you have driven for a while and stopped the engine.I was thinking fuel pump,but in that case wouldn't the car stutter or shake and misfire?
    Or could it be those aftermarket coils? Or something else? As i said,i've run out of ideas.
    Thanks for any help in advance
    Do you you get an oil burning smell in the car after it gets warm?
    Also since you said that issue appeared after changing the coils, you could put back in all the coils but the one that went bad and see if it fixes the issues. If it does you'll know it's the coils...
    Last edited by Breeze1; 04-22-2018 at 04:02 PM.

  3. #3
    Join Date
    Apr 2018
    Location
    Hartlepool
    Posts
    3
    My Cars
    2008 Bmw 318i E91
    I did the coil swap today and we can rule coils out,as it still doesn't start when warmed up. As for burning oil smell,i haven't noticed any.But as i was changing coil packs today i took a closer look at the engine and found that back of the engine is a bit oily,it seems that valve cover gasket needs to be changed,could that be the possible culprit?

  4. #4
    Join Date
    Jul 2013
    Location
    Casablanca, Morocco
    Posts
    780
    My Cars
    2001 e46 323i
    Quote Originally Posted by diselpowa86 View Post
    I did the coil swap today and we can rule coils out,as it still doesn't start when warmed up. As for burning oil smell,i haven't noticed any.But as i was changing coil packs today i took a closer look at the engine and found that back of the engine is a bit oily,it seems that valve cover gasket needs to be changed,could that be the possible culprit?
    Not to the point where it would prevent the engine from starting, no. Since it cranks when you try to start it it's probably not the starter either...

    Could be a sensor that works fine when cold but not warm. You can try to disconnect your MAF sensor next time and try it.

    When you say that it doesn't throw any code, do you mean on the dashboard's OBC? Or did you run a scan with an OBD2 scanning tool? If not you should get one of them, they're cheap and can help you out with situations like this.

    In any case and if the MAF is not the culprit try to have it diagnosed by a pro but I would advise you not to keep throwing money at it by randomly changing parts until it gets fixed because it could go a long way.

    Edit: the reason I asked you about a burning smell in the car is that when a catalytic converter (CAT) gets clogged it can prevent the car from starting, but it's usually associated with other symptoms, before it gets to that point (stuttering when warm and weird/oil smell in the car). If you want to get that one out of the way as well, just in case, you can do the following:

    - locate where your CATS are (right after the exhaust manifold on some cars, further down the exhaust line on others: not to be confused with the resonators, which don't have a wired sensor plugged into them)
    - go for the usual 20-30 min driving
    - pull over and immediately take a look at the CATS: if one of them is glowing red it means it's clogged. If that's the case you should immediately either change or gut it, because it can start a fire. And no matter what you do don't drive it over long distances.
    Last edited by Breeze1; 04-23-2018 at 11:53 AM.

  5. #5
    Join Date
    Apr 2018
    Location
    Hartlepool
    Posts
    3
    My Cars
    2008 Bmw 318i E91
    Ok i will check them,thanks for the advice.

  6. #6
    Join Date
    Aug 2020
    Location
    Northern ireland
    Posts
    1
    My Cars
    Bmw
    Quote Originally Posted by diselpowa86 View Post
    Ok i will check them,thanks for the advice.
    Did you find the cause ?

  7. #7
    Join Date
    Jul 2011
    Location
    Arlington, VA
    Posts
    9,933
    My Cars
    2018 BMW M240i
    The first step in diagnosing a problem is to scan the engine computer (DME in BMWspeak) for codes.

Similar Threads

  1. Replies: 4
    Last Post: 04-25-2019, 08:41 PM
  2. '84 BMW 325e doesn't want to start when engine is warm.
    By JCN1204JCN in forum 1983 - 1991 (E30)
    Replies: 1
    Last Post: 06-01-2014, 07:04 AM
  3. Replies: 3
    Last Post: 12-31-2013, 12:17 PM
  4. Replies: 3
    Last Post: 07-27-2013, 09:17 PM
  5. 1990 325ic won't start when engine warm
    By mlparker63 in forum 1983 - 1991 (E30)
    Replies: 3
    Last Post: 08-31-2005, 04:48 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •