[zerep1]

yeah it probably went rich and detonated i dont think theres anything major broken but the injectors might have not been properly seated or something i have heard of this before

[RoundelM240]

I don't suppose any of you guys remember the mid-1970s cars when all the emissions gear (air pump, catalytic converters, etc.) first appeared, but there was a really bad problem when shutting the cars off. They would "diesel" for several seconds with a loud clatter, which is essentially detonation due to the heat of compression and a lean fuel mixture. If something created this condition in the OP's engine, it's possible that some cylinder or cylinders ignited before Top Dead Center and tried to push the crankshaft backwards. The violent lurching that the OP mentions could have been caused by those kind of conditions within the combustion chamber - especially since our engines tend to run a little hot. A theory, but one that discounts the previous statement that you can't have detonation at idle.

[RoundelM240]

Originally Posted by tibra1

+1 on crap reliabilty; and lets face it being tuned ANY tune..never helps..the car is being pushed beyond intended limits..so have to factor this into the equation..

I would agree with you, except mine's been tuned since it had less than 10K miles on it, and my only problem was the HPFP issue. I only have 33K on it now, as these days it's only driven 1 or 2 days during the week (I work from a home office), but it's driven on weekends and out-of-town trips. I don't "baby" it when I drive it, but I don't really abuse it with drag-race starts or power shifting, or bumping the rev limiter either. Let's just say "spirited" driving. However, there is some truth to pushing the limits having a detrimental effect on engine life. It's just the degree to which it's pushed.

[vase330]

You guys have some really interesting theories on detonation. I have to admit I don't know enough to theorize one way or the other, but there was no way the car lurched like that and boomed like it did without some traumatic event in the engine. I am accepting the dealer's explanation on this one. I just had a call in. They confirmed low pressure pump is out and they have changed it, but haven't put things back together to test and see if there are other issues.

I asked again, and they confirmed detonation from suddenly going lean. I will honestly be amazed if something is not broken or cracked inside after what I experienced. But if it runs right, then I don't want them opening it up to do "exploratory surgery". But this is just hoping for a good outcome knowing there might not be such an outcome. SA said the tech working on it is optimistic it might be alright though.

[vase330]

Here is the latest: I need some advice what to do now. I don't want to spend a ton of money on this and I fear its headed that way. What can I do?

They put a new pump in. There is fuel pressure etc.... sad part is they can't get the engine to idle beyond couple minutes and it wont take any load at all. SA said its running real bad, but they are going to take a fuel sample see if there is contamination. Thing is last time I put fuel in it was 93 Octane, the tank was full, now I barely have a quarter left, and haven't filled up in 3 weeks. I think its unlikely to just impossible that fuel is contaminated. I drove the car 20 miles or so before this happened. Makes no sense at all. What do I do now? I really don't want to go into engine yet.

[cn555ic]

At this point the dealership is clueless themselves and with each hour trying to troubleshoot the car it's going to cost you. I think they would need to open the engine at this point because fuel contamination is not why your car won't work at this point. Damn I dunno what I wOuld do in your case and this issue has to be one of the first cases with this problem.

[cn555ic]

Either take it out of the dealers hand and take it to an Indy shop and let them diagnose the problem as it will be cheaper at this point. BMW charges I think 185 dollars or maybe even more per hour of labor

[vase330]

Yeah they don't know what is the matter. Maybe I should ask them to not do fuel sample at all, no way its contamination, its just not. Maybe its time for them to check inside the engine? Anyone know what the best diagnostic route is? This sucks.

[Mr_PharmD]

The dealer needs to pull the codes and go from there.

[tibra1]

This is beyond pulling codes.. internal engine inspection if gonna have to be done. I would call my insurance company see if there is any coverage..likely to get expensive

[Brey335i]

There is no further option other than taking the engine apart. I would take it to an indy shop

[Joshboody]

i would think there's positioning indicators to check crank and cam alignment... not sure how difficult it is to access though.

[boom]

Have them do a compression test. That should be a standard service and will tell you a lot. If there is low compression, add a half a teaspoon of oil to the cylinder and recheck. If compression rises, you're rings are bad - the oil temporarily seals. If compression doesn't rise it could be valves or hole in the piston. If there is low compression you then do a leak down test to find out if it's a head gasket, rings, valves, etc.

As the car won't take load and only idles briefly I'm thinking you jumped timing. Low compression in all cylinders would indicate this.

[vase330]

Boom, can't they check alignment without all these tests? Wouldn't the ECU know if alignment was off and throw some sort of codes? I am thinking of options for next steps and suggestions to avoid going on a wild goose chase at dealer rates. I am thinking maybe take the car to ATS Motorsports in MD, its a racing shop but they are just as expensive. Thing is sometimes you wonder whats going on in dealerships. Where are all the knowledgeable folks on E90post? Shiv? Any Tuner? Anyone there. Sniz, what do you think man?
I am uncomfortable with this contaminated fuel thing honestly. There is no logical way a ran 3/4 of a tank without an issue at all if the fuel was contaminated.

[Tiago@VRSF]

A compression check would be the first thing I'd do if this car was at our shop. If it's stumbling and not handling load. You have a timing chain in the car, these don't skip teeth often like a belt does. I've personally never seen a timing chain skip a tooth. I have seen incorrectly installed timing chains that were off a tooth though.

Fuel contamination is a waste of time.

Detonation is common in almost every car and every tune. A few counts of knock/pre-detonation in a short amount of time isn't enough to affect the motor, but a lot of knock in either a short or long amount of time will cause that.

In most cases, pre-detonation occurs from running too lean (not enough fuel, too much air) in the air/fuel mixture or improperly setup ignition advance/timing.

In your case since the LPFP failed, I'd imagine you were running lean a bit before it failed completely but all of this is just guess work. The only way to know if the there is a mechanical problem is to do a compression test to see if the rings/valves aren't the problem.

Compression, spark & fuel. You need those 3 in order for a motor to run, whether it's a Buggati Veyron or a 2 stroke lawn mower engine. It's that simple.

[Tiago@VRSF]

Originally Posted by vase330

Boom, can't they check alignment without all these tests?

They can, but checking compression is just as easy as checking the alignment on the timing chain. If your tech hasn't done this yet I can't even imagine what they are doing over there.

[vase330]

Thanks Tiago, I think maybe request a compression test be performed next. I'll call them in the AM tell them not to bother with the fuel test, I don't think it makes any sense at all. I was also wondering if you ought to get a software update after LPFP replacement and if that can cause this. I don't know if or not they updated software. I am not knocking them, they know a lot more than I do armchair quarterbacking here, but its my $$$ being spent so all I am attempting to do is limit the money needed to get this right.

[Tiago@VRSF]

No software update should be required to get the car back to running condition. I'm sure resetting the ECU would help get the fuel trims back in line though. The can generally be done by unplugging the negative terminal for a certain amount of time.

[nitehawk]

I totally agree with the compression test. Its simple enough and will give you a good indication of what lies ahead. I'm surprised they're even contemplating contaminated fuel...
If you fill up at this station regularly, its unlikely that this one fill-up did you in, especially on the last 1/4 tank.

[Tiago@VRSF]

Originally Posted by nitehawk

I totally agree with the compression test. Its simple enough and will give you a good indication of what lies ahead. I'm surprised they're even contemplating contaminated fuel...
If you fill up at this station regularly, its unlikely that this one fill-up did you in, especially on the last 1/4 tank.

I'm assuming by "fuel contamination" they mean "this dummy filled it up with diesel instead of premium". Fuel contamination is the last thing I'd check.

[MilehighM3]

Originally Posted by vase330

Boom, can't they check alignment without all these tests?

Compression test is far easier than checking timing. They'll have to pull the valve cover to do that. They'll have to use the cam timing fixtures to verify timing. With the engine stalling under load, there are some other possibilities as well. Compression test is a great starting point. Plugged cats can make a car stall or unable to rev up, especially under load. I'm guessing you don't have cats though? They should also do a fuel volume test, pressure is only part of the equation. If the fuel was bad, not saying that it was, you may have a clogged filter as well which will cause lean conditions stalling etc.
Just a couple of thoughts off the top of my head.

I've also seen new turbos have oiling issues and seize up. Usually only one, but I have seen a couple lock up. Never on the same car though. Hopefully they have the shop foreman helping out on the car at this point. If not, they should.

Keep us updated, and best wishes for the cheapest bill possible.

[J02 335i]

Crazy story, good luck op, compression test and go from there as stated above. If that dealer knows how to. Fuel contamination, don't think so. Don't let them waste your money. In my ten years of being a tech and shop owner I have never come across a car that has had contaminated fuel.