[WilliamE92]

Didnt realize this thread was still kicking around.

A little update, my car has been suffering from erratic starts but not necessarily long cranks, it only cranks for a second or so but it catches like a couple cylinders are firing for 1/2 a second then catches fully and starts. Dont know how to classify that. It sounds like I'm starting a car with 100k miles on the clock basically.

This only happens sometimes, then other times it starts instantly.

Anyway I switched from shell to chevron and havent had any true long cranks since I posted this originally, so I gathered up the stones to try the JB+ again.

I threw my JB+ back on yesterday and drove it 100 miles or so at 50%, no problems. No long cranks when I got home, no long crank this morning. So I turned it up to 75% today and drove it another 50 miles without any problems.

We'll see if it long cranks in the morning, if not then I think that the fuel was the issue (in addition to a possibly weak pump).

[deletedelete]

Its possible you had a bad batch of gas. Ive had the jb+ at 100% for six months with zero issues. I doubt the jb+ could affect the hpfp.

But as we all know, the hpfp can fail just by looking at it. I hope your hpfp is ok. Ive seen you yell about it in other threads just like me.

[mad chemist]

I've been running SSTT (~ JB+ @75%) on 93 octane for 21,000 miles. Car has never missed a beat. I have BT and have never thrown a related code.

[twin turbo]

I got my BT cable today, gonna check for codes this weekend. I really don't see how the JB+ could cause long cranks, but snsn seems to feel differently. The car runs great, it has never sputtered or hesitated, just the occasional long crank.

[SpaceGhost]

It doesn't seem reasonable to attribute long cranks to the JB+. HPFP failures are common on 335s across the board. Many 335s have bad HPFPs. Many335s use JB+. Seems like more of a coincidence than a cause and effect scenario to me.

[PeteW84]

2,000 miles with jb+ @90% without a single hickup. I only use Shell V-Power 93 octane.

[Jrlelli]

so is it safe to say that the gas was the issue. I have my JB+ here staring at me saying it wants to be in the car but i would really hate to screw up the HPFP. Now how would one know if the HPFP is failing? Are the long cranks at start up an indication of a problem or something else? I want to install this bad boy but i am being hesitant.

[twin turbo]

Just scanned with BT software, no codes at all. I've been running the JB+ at 100% for a few months. Just recently started experiencing long cranks. It only happens when the car has not been started for 8 hours or more. It never happens when the car was driven recently and the engine is warm or hot. No hesitation on the road at all, car runs strong. I would think if the fuel pump was failing, I would experience long cranks whether the engine was hot or cold. Any opinions?

[skate_E92]

Originally Posted by twin turbo

Just scanned with BT software, no codes at all. I've been running the JB+ at 100% for a few months. Just recently started experiencing long cranks. It only happens when the car has not been started for 8 hours or more. It never happens when the car was driven recently and the engine is warm or hot. No hesitation on the road at all, car runs strong. I would think if the fuel pump was failing, I would experience long cranks whether the engine was hot or cold. Any opinions?

ive never tuned my car and just got my pump replaced for the 2nd time at 8,000 miles and had the exact same issues as "twin turbo" so dont thinks its the tunes fault

[Jsnscot]

I'm going to say it's the JB+ fault, I love BMS and their products but there's something wrong with the JB+

[Jrlelli]

ohhh great dont say that

[ZTUNER]

Wanted to add a data point - JB+ at 100 % and no long cranks or codes so far.

Harry

[Mike@N54Tuning.com]

Originally Posted by Jsnscot

I'm going to say it's the JB+ fault, I love BMS and their products but there's something wrong with the JB+

It is technically impossible for the JB+ to have a direct positive or negative impact on the fuel pump. The JB+ with relation to the fueling system is identical to the JB1, JB2, and SSTT.

I see unmodified cars at the dealership daily with long cranks, and BMW has sent a letter out to every N54 owner informing them of the fuel pump problem. It is possible that if your pump is on the edge of failure asking it to produce 30-40hp more will push it over the edge, but a healthy pump will not fail as result of this. There are over 1000 JB+s in use now and if a correlation existed there would be hundreds of people chiming in that their FP failed a few days after installing the JB+, don't you think?

Mike

[Fraggy]

As far as I know, the behavior of the pump is not related tune. Its related to RPM.

[Jrlelli]

Originally Posted by Mike@N54Tuning.com

It is technically impossible for the JB+ to have a direct positive or negative impact on the fuel pump. The JB+ with relation to the fueling system is identical to the JB1, JB2, and SSTT.

I see unmodified cars at the dealership daily with long cranks, and BMW has sent a letter out to every N54 owner informing them of the fuel pump problem. It is possible that if your pump is on the edge of failure asking it to produce 30-40hp more will push it over the edge, but a healthy pump will not fail as result of this. There are over 1000 JB+s in use now and if a correlation existed there would be hundreds of people chiming in that their FP failed a few days after installing the JB+, don't you think?

Mike

I didn't get any letter. Why is that? Should I call the dealer I got it from?

[twin turbo]

Car took 5 seconds to start today, haven't driven it since Friday. Car started fine when leaving the restaurant. It's almost like the fuel is draining out of the fuel lines. You guys that are experiencing long cranks, does it do it every time or only after the car has sat for a while?