Effin stranded😐

[wheela]

Well, just got a limp mode and misfires on the highway after letting off. Pulled over and the shaking was pretty bad. Turned it off to reset the fuel cut, but it was even worse with smoke and fuel smell when I turned it back on.

Checked codes and had high pressure fuel low codes, multiple misfire, and cylinder 4 deactivated. I tried power cycling it one more time to see if I could limp home, but it got yet even worse, totally bucking and grinding sounding just driving a few feet, so here I sit with a tow truck on the way. It was way way worse than last time I was misfiring from a loose plug and coil. With the horrendous bucking and grinding sound, I shut it back off right away. I pulled codes again, but the only new code seemed to be a cylinder 5 deactivation (on top of the others). Since I didn't have symptoms until I let off (from WOT) I was worried it could be crank hub, but none of the codes seem like they'd be related to that.

Hopefully something simple. If it's hpfp, I have a Dorch stage 2 at home waiting to go on, lol.

2015 X1, n55e

 

[wheela]

My car has felt slower/less consistent lately, and some intermittent bad logs, but no codes.

I guess something was on the way out.

 

[CalvinNismo]

Sorry to read this wheela! Are you going to swap the HPFP?

Edit: This thread has a couple of interesting bits in it.

Diagnosing faulty LPFP vs. EKP vs. HPFP

Diagnosing faulty LPFP vs. EKP vs. HPFP

f30.bimmerpost.com

I want to say EKP is what I would look at first (cheapest).

It could be injectors, but seems unlikely it could be 2 at once in my opinion (unless you had a really dirty tank of fuel or something). One of my injectors was under performing when cleaned and tested, so I bought a new set.

LPFP could be the culprit, but I would look at the EKP first.

With the HPFP being mechanical, if your car now runs fine(ish), mechanical items don’t generally fail intermittently (as someone said in the thread).

 

[wheela]

Thanks for chiming in and sharing that thread! I think I've read that one before. The intermittent things I've seen lately have been pretty subtle, like some days it feels sluggish, and other days not. Some days it feels extra slow vs. just normal slow. To the point where I wonder if it's just in my head? Ugly logs are more concrete, but I had (perhaps mistakenly?) chalked that up to having a Frankenstein mix of fuel in the tank (had to travel out of state alot the last couple months and had no access to my normal 93 10% ethanol, just ethonal-free 91, and ethanol-free race gas...)

The misfires and limp mode haven't been intermittent. In hind site, I realized when the tow truck was dropping me off last night - I totally forgot to clear the codes after reading and screenshotting them Do you know if cylinder fuel cut from misfires resets automatically when powering the car on and off, or do I need to actually clear the code for the cylinder fuel cut to reset?

Either way, it seemed to get worse on each restart. My codes after initially turning it off only showed #4 deactivated. First attempt at restarting it fired right up buy was shaking uncontrollably from all the misfires so I shut off and read codes again. This time #5 joined #4 in deactivation. My 3rd attempt the car turned over without firing up for a good 2 seconds or so, and when it finally lit up, it was barely able to keep running. I've never once had any kind of long cranking before.

I guess I can't say for sure if this issue is intermittent since I forgot to clear the codes before restarting. But it seemed to get worse each attempt, so I think something fueling related died for good.

Since I've never had any intermittent issues before, I'm leaning a little more towards hpfp gave up the ghost vs. EKP, but it could be either. I agree, injectors seem unlikely since 2 cylinders are implicated. It's at the shop, so we'll see what they come up with, and go from there

 

[wheela]

They're still trouble shooting, but so far the rail pressure sensor definately shit the bed - it's reading 5 bar with the rail disconnected from the pump outlet. They replaced sensor, but #4 was still misfiring. They swapped coils and plugs, wet plug, and misfire stayed on 4, so leaky injector.
I'll have them replace all 6 since I'm at 70k. Couldn’t check the hpfp yet since #4 was misfiring so badly.

About the leaky injector - I've done the check recently where you let off the gas and whatch AFR settle at 232 or wherever it pegs, and everything has been fine. Seems odd to have a bad rail sensor and leaky injector at the same time? Any thoughts on potential relation vs. councidence?

Now I'm wondering if I should just have them throw the Dorch stage 2 on, regardless of condition on the stock pump (stock pump has 70k miles on it)? I was holding off on the Dorch until I was closer to getting my speedtech kit installed, just to avoid accumulatimg wear & tear on the Dorch until I actually need it. Hopefully my speedtech kit will go on within the next 5 - 10k miles.

Any thoughts from the peanut gallery?

 

[wheela]

Think I'll hold off on the pump for now (unless they find some issue with it after replacing injectors). I can do the pump later on my own and save some cash.

 

[wheela]

The plot thickens. So they replaced injectors, reset adaptations, but it dies after about 10 minutes.

They let it idle for 10 minutes, but it started misfiring badly when they gave it gas and it died. They were monitoring BOTH low fuel pressure AND high fuel pressure, and they said both looked good. He said low pressure was around 77, and when the misfiring would start it would go up to 80psi. He said it was going lean, but there are no codes. I asked where the trims were but didn't get a straight answer.

They wanted to go back to stock for troubleshooting, but I don't want to since I have MHD and a catless downpipe. We agreed he'd go drive it a while to see if adaptations would adjust to correct whatever is going on.

Any ideas what this could be? It was fine for 2+ years on MHD OTS tune. Ltft typically around 5-7% before this. He did say #4 injector was leaking like a sieve, and there was fuel in the oil. Could that be related? It couldn't have been leaking for long, in fact I was wondering if they got some foreign material in the rail when they disconnected it to check the rail sensor - but that probably wouldn't have gotten fuel in the oil that quick, no???

Could this really just be the adaptations need to settle back in? I believe he coded the injectors as he mentioned reprogramming for the new injectors individual flow values.

I'm befuddled. Never had any issues before, or immediately after flashing. I'd welcome any thoughts.

Edit: for what it's worth, he said he DIDN'T reset the vanos adaptations, as he's had problems in the past doing that to cars. Also, he changed the oil because of the leaky injector/fuel smell in the oil.

 

[wheela]

They called back, if I understood correctly, it sounds like they may have re-used the old decoupling elements when they initially put in the new injectors. With new decoupling elements in place, they drove for 45 minutes and let it idle for an hour, and suposedly everything is fine now. I'll pick it up tomorrow and report back if anything still seems amiss, but hopefully that was it

 

[CalvinNismo]

Glad it sounds like it’s sorted. If the injector was leaking and the oil stank of petrol it’s definitely worth changing it, so that’s good they did that. If you’re over fuelling like crazy, some not combusted fuel can definitely slip past the piston rings.

I’ve been meaning to reply since the weekend but have been super busy! Did you go for Bosch or genuine injectors? Or EU5 or Precision? Or something else?

Just thinking out loud, if the LPFP targets 5 bar fuel pressure, it kind of makes sense that the rail sensor minimum value is 5 bar, no? If the HPFP is doing what it should (and injectors aren’t doing their best colander impression) then the value should always be greater than 5 bar (72psi).

 

[wheela]

Glad it sounds like it’s sorted. If the injector was leaking and the oil stank of petrol it’s definitely worth changing it, so that’s good they did that. If you’re over fuelling like crazy, some not combusted fuel can definitely slip past the piston rings.

I’ve been meaning to reply since the weekend but have been super busy! Did you go for Bosch or genuine injectors? Or EU5 or Precision? Or something else?

Just thinking out loud, if the LPFP targets 5 bar fuel pressure, it kind of makes sense that the rail sensor minimum value is 5 bar, no? If the HPFP is doing what it should (and injectors aren’t doing their best colander impression) then the value should always be greater than 5 bar (72psi).

Thanks for your reply! Just picked the car up, everything seems fine so far Trims are better Not sure what injectors they used since I didn't buy them myself It's whatever eu5's the stealership goes with. It was sooo much more that if I bought from fcp and did it myself

Actually, that 5 bar rail pressure reading was with the rail inlet physically completely disconnected from the hpfp, so there was definately no pressure on the rail. But, I did my psi conversion wrong earlier, when compared to the hpfp target, 72 psi off isn't as bad I was originally thinking. Maybe my issue started with the stuck injector and they found the poor reading rail sensor along the way.

 

[wheela]

Car is running great, and fuel trims looking better than ever now Also, a weird rattle I had started hearing on cold starts recently (details in thread linked below) also seems to have been resolved by replacing the injectors and rail pressure sensor Not totally sure why, but I'll take it

Very brief rattle at cold startup. What is it?

Hello all, The last couple months. I've noticed that when starting the motor cold, there is a very brief rattle right as the motor starts to turn over, and is gone as soon as the engine comes to life (gone before rpm's come up). Almost like a really fast snare drum triple. I tried recording...

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