2009 JCW R55

Just had the light come on and it's running very rough, no power. I pulled these codes, any ideas where to start? Perfect timing since it's about 15 deg out now.
Plugs changed recently, HPFP replaced as well.
cheers

Monitoring Ignition
Code: 00273E
Misfire, a plurality of cylinders: injection is switched off
Code: 002781
Misfire, cylinder 3: injection is switched off
Code: 002775
Misfire, cylinder 1: Injection is switched off
Code: 002772

 

Swap out the coil packs and see if misfire moves with it. Cyl 1 is the left most when facing the engine.

 

Just gave it a try (fun working on the car in single digit temps). Unfortunately same codes came back. It's going in to the shop tomorrow, hopefully nothing big my wallet can't handle it again just yet.

 

Swap plugs and see what happens.

 

Apparently it's got an actual hole in a valve. About ½ compression in cyl 3. They want all my money plus 20% to fix it-I love this car, but holy crap.

 

Sorry to hear that...If you want, I can take on the repair. Check my posts and albums. I did over 10 minis and 2 rebuilds for NAM members (one in MD and the other in IL)

 

Thanks for that offer. I sort of feel stuck at this point. I've got a loaner car and it's 7 deg here. I'm down to one vehicle so time is a factor. Normally I'd be thinking about doing it, or getting someone else involved, but I guess I'll just melt a credit card this time.

 

if that is the case...check car-part.com for an engine and then have someone installing it. you'll need more than one CC to melt...get quotes from shops and then roll the dice. Im always ready to help

 

Sad update. Had the dealer do it, cost a fortune. Two days ago it did the same thing again. Good news is it's under warranty for the repair, bad news is they need to know why it did it. The car has a slightly bigger turbo and a mild tune, def not trying to push the envelope. This was just a more cost effective way of replacing the factory turbo, dealer suggested. Any thoughts appreciated.

 

what was the repair? an engine swap or rebuild? what did it do again? poke a hole in the valve.

 

Yeah, what he said ^ Do you mean you have another hole, or just the codes? Did you visually see damage in the valve that the dealer removed? Was it just one? You wording is singular, but you had codes for two cylinders.

 

One exhaust valve developed a hot spot and burned right through, I believe cylinder 3. I have the valves. I believe same cylinder again. The top end was completely rebuilt.

 

So no explanation then for what initiated the burn or why two cylinders missed? Sounds to me like a problem outside the head and the head just couldn't stand it anymore.

 

the question is, what is the definition of top rebuild? did they just replaced the valve and called it a day? or they replaced the head entirely? or did they replace valve, guide, and stem seal too?

it seems that there isnt enough lubrication going up the engine!

 

No clear evidence of anything last time. This time they think possibly the electrode from plug broke off (it was gone) and created the hot spot on the valve. No coolant/overheating issues that I'm aware of. Maybe both cylinders were acting up, seat leakage?, and the other just won the race? I'm lost in what might cause this.

Supposedly complete, proper rebuild. All new parts-valves replaced, head checked, lapped.

 

If the spark plug broke off, there couldn't be a hot spot - there's not going to be combustion!

I am thinking a blockage downstream or lack of fuel causing a lean condition. Although, a bad lean condition would've been reported by the O2 sensor, so I am back to downstream obstruction like a clogged cat. Lack of lubrication wouldn't cause exhaust temp to go up like that.

 

Maybe heat caused the plug tip to come off? A bad injector(s), maybe lean in 1 or 2 cylinders, but not enough to trip O2 sensor? I've had a clogged cat in another vehicle before, it was super obvious in running, bogged down like it had a ½" exhaust pipe on it. Oil level is always checked and never low, not that it couldn't be a blocked passage somewhere I guess?

 

If it got hot enough to break the spark plug, then that is a symptom and not the cause. It still doesn't explain why, and I wouldn't let your mechanic charge another dime until he can come up with an explanation that makes sense under scrutiny. The O2 sensor *should* let you know before it becomes so lean you have a problem, but I am guessing - it is logical to leave this option on the table then. Going back a couple steps, why did you replace the HPFP in the first place? Reading in between the lines, this was done prior to all of these symptoms? If that was replaced due to a bad diagnosis of the current problem, there may be some older clues as to what happened.

 

I agree on the plug. They clearly missed some element. Whatever they are doing related to this job is covered under warranty at least. O2 sensor is fairly new, last summer. HPFP was replaced under warranty in Sept. I had rough idling and low pressure at fuel rail. Testing by dealer confirmed.

ps thanks for the info back and forth btw

 

Thanks for letting me! This is always good practice for me. My automotive background is very strong but also very conceptual and lacking in hands-on experience, so feel free to call me out on anything and I'll try to be clear when I am assuming. That being said, I was working at Bosch when BMW started racing the N20, so I did the ECU software for the GrandAm (or whatever the series called itself) program at the time.


Going back to the low fuel pressure, that can cause a burned valve, but having the dealer confirm the bad pump is a big point. Maybe the new pump went bad for the same reason? It could be that the low pressure pump isn't running well, and this could result in cavitation (where the fuel in the high pressure pump starts to boil in the suction stage). Over time, this can cause HPFP failure.

 

Very cool on the Bosch work! low pressure pump is something to look intro I guess

 

If it was the same cylinder again then that cylinder is running too lean, the burned valve and sparkplug are the symptom. Check the fuel injector for that cylinder.

 

Just heard from the dealer, claims it was a different cylinder. Also, suggesting the tune could be to blame.