Fuel pump woes. . .

[DataStream18]

Ok alot of my buddies drive e9X and a few of them have been complaining about the same exact thing I have been about rough starts in the morning on cooler or colder days untill it heats up. Or the studering (sp) that happens when you accelerate untill its warmed up. I did some research and watched posts about it and found that issue on theirs to be the HPFP. (High pressure fuel pump)

That got me thinking about my issues that i still have. I ran the techron through it, new plugs and all that but if they're having exact issues with their HPFP I must be as well right? I know we have a fuel pump in the gas tank but is there multiple like a low end and a high end?

[aerobod]

Originally Posted by DataStream18

Ok alot of my buddies drive e9X and a few of them have been complaining about the same exact thing I have been about rough starts in the morning on cooler or colder days untill it heats up. Or the studering (sp) that happens when you accelerate untill its warmed up. I did some research and watched posts about it and found that issue on theirs to be the HPFP. (High pressure fuel pump)

That got me thinking about my issues that i still have. I ran the techron through it, new plugs and all that but if they're having exact issues with their HPFP I must be as well right? I know we have a fuel pump in the gas tank but is there multiple like a low end and a high end?

No HPFP on any E85/E86 Z4, LPFPs in the fuel tank only.

[DataStream18]

Does anyone know where the F*** this is located, the TIS doesnt tell me crap and I'm gettin frustrated. Neither does google or search. . . .

[BTM]

You can't find the HPFP because you don't have one.

[claritycheck]

Originally Posted by BTM

You can't find the HPFP because you don't have one.

This.

[Jmanscotch]

Cold start woes with the 'hesitation' under WOT can also be a symptom of worn VANOS seals....

[RevsPlease]

Originally Posted by Jmanscotch

Cold start woes with the 'hesitation' under WOT can also be a symptom of worn VANOS seals....

This. The shuddering, hesitation and rough cold starts are all symptoms of worn Vanos seals. Check out http://www.beisansystems.com/ for more info. They make the best replacement seal.

[Donovan303]

I'd also say it is the vanos seals. I had similar symptoms that went away when I replaced my seals. Beisan has a great step by step procedure for this and I added some Z4 specific things here:http://www.zpost.com/forums/showthread.php?t=615850.

You will need about 4.5 hours for this. If you have not done your valve cover gasket before, go ahead and plan on that too.

Cheers,
Donovan

[DataStream18]

I will definitely look into the Venos repair kit! Granted the car is 8 years old but it JUST turned over 60k todays ago and this issue only started when it was starting to get cold. Also I'm not looking for the HPFP just the regular one in the fuel tank, i forgot to mention this b/c i was po'd and had a head ache that day. I know its in the fuel tank just not sure how to get to to it.

Thanks for all the help!

[puciorek]

I've got the same problem...however the car only has 22k miles.
there is a post that talks about this...see following link:
http://www.zpost.com/forums/showthread.php?t=586436

I'll take mine to the dealer since it still has warranty left...see what they say(?)

[Donovan303]

Originally Posted by DataStream18

I will definitely look into the Venos repair kit! Granted the car is 8 years old but it JUST turned over 60k todays ago and this issue only started when it was starting to get cold. Also I'm not looking for the HPFP just the regular one in the fuel tank, i forgot to mention this b/c i was po'd and had a head ache that day. I know its in the fuel tank just not sure how to get to to it.

Thanks for all the help!

I think the fuel pump is in the tank and to get to it you remove the exhaust, insulation, and also the fuel filter. The pump should be visible after the filter is removed.

[DataStream18]

No sooner I figure it out and come to tell all, you answer it! Hahah Thanks! Yup its there. I ordered my VENOS rebuild kit (4 O-Rings and 2 washers) as well as my valve cover gasket kit. SO if its here this weekend It shall be re built!

[DataStream18]

Originally Posted by puciorek

I've got the same problem...however the car only has 22k miles.
there is a post that talks about this...see following link:
http://www.zpost.com/forums/showthread.php?t=586436

I'll take mine to the dealer since it still has warranty left...see what they say(?)

Any chance after you cracked your coolant pipe to get it outta the way and everything was bolted back together finished up, did you see your temp gauge raise slower then it used to?

I finished mine up in more then 5 hours and and everything was good, i just notice my temp gauge doesn't rise as fast as it used to, not that that is a bad thing just curious.

Also there is no more rough starts or idles!!!!!

[Shipkiller]

Just remember, it will take up to 500 miles of city style of driving to get the new Vanos O-rings to seat/break in properly for full effect.

I did mine back in 2008.

[DataStream18]

Originally Posted by Shipkiller

Just remember, it will take up to 500 miles of city style of driving to get the new Vanos O-rings to seat/break in properly for full effect.

I did mine back in 2008.

Thank you for letting me know, I thought there were a few miles to put on it but I didnt know how much.

[Alexmsk77]

recommend that you read the information about the repair kits for BMW vanos online
www.vanos-bmw.com

[thelinux]

I have simillar symptom. But mine is 2008. So no vanos , no hpfp.... I get no code. what else can be the cause?

[StickMon]

Here's another possibility.
Sounds like the "T-Shape Idle Regulating Valve" is a source of potential poor idling when cold.
I'm going to buy one to put in my spares bin.
The thread is for an ///M. Not sure if the non-M has a similar widget.

[Shipkiller]

Resurrection of a two year old thread just to hawk his company.............