Hard Start Runs Rough 1st Time Cold

[2008E82128]

Hello Ladies and Gentlemen.

Im new to BMW but not new to car repairs as many, many of you can relate.

We purchased a 2008 128i with 135000kms in June. Fun little car. It came with what youd expect from a trade in. Oil changes done but nothing else. I have done my research and have replaced ignition coils and plugs with (Bosch coils and PLZFR6A-11S NGK plugs) first line stuff. Ran perfect like a tune up should.

Now that its cooler out, when we first start the car in the morning its a hard start/runs rough if i can keep the rpms up until it smooths out. Then good all day. Research says if its turbo it HPFP. We dont have HPFP.

Im sure I have a fuel filter/fuel pressure regulator as regular service in my future but Im having trouble linking the two.

No CEL.

What am I over looking/not seeing? Any help would be greatly appreciated.

Thank you

[NorthernDancer]

Well when you give your location as "Earth", it doesn't help us direct you to a good local garage. It's nearly impossible to diagnosis an issue like this with info provided (as Mike Miller would say).

[2008E82128]

Im in the east GTA. What other info is needed? I understand the most difficult diagnosis and repair is that intermittent. Am I able to check fuel pressure anywhere? A port? I hate the no oil dipstick.

[Ross4ze]

Originally Posted by 2008E82128

Im in the east GTA. What other info is needed? I understand the most difficult diagnosis and repair is that intermittent. Am I able to check fuel pressure anywhere? A port? I hate the no oil dipstick.

+1

[NorthernDancer]

https://www.trilliumbmwclub.ca/

the Trillium BMW Club in Toronto has many members and members help other members. Likely quite a few in the club own cars with N54/N55 engines and are are good resource to help you. And, if they can't help, they know the best indy garages.

That's why it's always good to know where you live.

[GerryT]

If I understand correctly OP has N52 not N54.

Shot in the dark, but I am currently reading up on the DISA valve (I have a 330 with 270k kms) and some of the symptoms of a failed DISA match your description. Hope that may help you get closer to the problem. Gerry

[MightyMouseTech]

Originally Posted by GerryT

If I understand correctly OP has N52 not N54.

Shot in the dark, but I am currently reading up on the DISA valve (I have a 330 with 270k kms) and some of the symptoms of a failed DISA match your description. Hope that may help you get closer to the problem. Gerry

128 does not have DISA.

[Gangplank]

Originally Posted by MightyMouseTech

128 does not have DISA.

It does if it's the N51 SULEV motor.

[MightyMouseTech]

Originally Posted by Gangplank

It does if it's the N51 SULEV motor.

I stand corrected. I am in Canada, same as OP, and we never got that engine.

[2008E82128]

Thank you to all.

My information is that its a N52, its NA, and as far as I can tell not DI. Thus omitting the HPFP. Bit more to the story and making it more difficult. After the hard start runs rough issue, it starts and runs perfect for a month or two of daily driving. At first I thought weather as it didnt seem present in warm weather and got more often when it got a little cooler but I dont believe thats the case.Everytime its the first start of the day. Thats the only thing that is consistent. Im thinking fuel. Either too much or not enough when the condition arises.

Northern dancer thank you I will try them.

[Gangplank]

You might want to search around the forum for the NGK vs BMW plugs. I know they are supposed to be the OE equivalent but I believe the BMW Bosch plugs are better somehow.