Long crank while warm

pysical

Sergeant
Jun 16, 2017
471
108
0
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2009 335xi E90
When I start my car in the morning, it fires right up instantly. If the car gets warm and I shut it off, wait ~30minutes to 6.5 hours later, it is a long 6 second crank. I have tested it at a 30 minute mark and it is long crank and even at 6.5 hr it is long crank. I even did a test at about 5 minutes and the car didn't start up as quickly as it normaly does. It crank liked 2-3 times stumbled to start, had a rough idle for half second then ran fine.

So somewhere between the shutdown and about 5 minutes some stuff is going. I am not getting any codes except some 2AAE, 2AAF (inactive) codes. Injectors are index 12, hpfp is a ebay one from about 3 or 4 years ago (but seems to look fine in the logs).

When I shut the car off, I have noticed that the rail pressure drops down to about 93 psi, and the LPFP goes up to about 82 psi. This happens in less than 30 seconds after shutting the car off.

I am running 93.

Things I have tried/checked:
Swapped crank sensor with another
Will be replacing ground strap in 2 days when it gets here.
Peaked around Inpa while car was running and found this () Not sure if this has anything to do with it but its the reason I am gonna replace the ground strap.

Log: https://datazap.me/u/pysical/warm-start?log=0&data=3-21
First log is a long crank start and short idle
Second log is a start right after the long crank, and then shutdown
 

135itp

Private
Dec 6, 2018
34
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09 135i n54 AT
high pressure fuel pump is a common for your concern of a long crank when warm. there is a SIB for it if you google search, IIRC
 

pysical

Sergeant
Jun 16, 2017
471
108
0
Ride
2009 335xi E90
high pressure fuel pump is a common for your concern of a long crank when warm. there is a SIB for it if you google search, IIRC
Yeah my car doesn't apply to it. I don't mind buying a HPFP from FCP Euro if I need it. But I don't want to buy one if I don't need it.
 

135itp

Private
Dec 6, 2018
34
28
0
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09 135i n54 AT
replaced hpfp with new one from FCP Euro and nothing changed.

Atleast you can rule out the eBay HPFP now. Faults the same?

Based off your logs, you had a rebuild few months back? issue come up all of a sudden or do you remember changing anything when this started?

Here is some more info too, hope this all helps.
 
Last edited:

pysical

Sergeant
Jun 16, 2017
471
108
0
Ride
2009 335xi E90
Atleast you can rule out the eBay HPFP now. Faults the same?

Based off your logs, you had a rebuild few months back? issue come up all of a sudden or do you remember changing anything when this started?

Here is some more info too, hope this all helps.

I had this issue before but engine build but it was with E85 only. The new HPFP didn't change anything that I can tell, but I am sure it helped with something, or will help once the boost kicks up another 10 psi.

I did some more looking around and I am beginning to think it is the injectors. I stuck a borescope down the spark plug holes and it looks like the injectors are dripping. Directly under the tip has like a splatter circle and then a little trail running down to the bottom of the piston. They are index 12 with a few thousand miles on them. But they sat out the entire time my engine was being built (6+ months). Something may have happened to them. At this point I am thinking when they get warm the expand and cause issues.

Luckily I have them all warrantied.
 

Bmwfixerguy1

Lieutenant
Jun 5, 2017
875
292
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07 335i MT
Leaking injectors is a common cold start issue not so much on hot starts but if you can see a physical leak than I would replace those injectors first as they can make it take much longer for HP to come up to a working level. Also depending on how you fuel system is ran and environment don't rule out vapor lock, very common in n63's
 

pysical

Sergeant
Jun 16, 2017
471
108
0
Ride
2009 335xi E90
Found the issue. Turns out the port injection injectors that I just checked not to long ago decided to mess up. Took to injector shop and one of them is stuck open. Replaced and now starts and runs much better.