[AndrewC1989]

Not to be an ass but it's stories like this that make me 100% content with my stock tune

[Got f1?]

Originally Posted by AndrewC1989

Not to be an ass but it's stories like this that make me 100% content with my stock tune

I don't disagree. I have spent my mod dollars on suspension, brakes (pads), wheels and some aero to make the most of the power I have. It would still be helpful to learn from this and establish a solid guess on cause. I have an M2C, so that has its own issues, but knowledge would be a good thing.

Seems to me there is more to know from OP to potentially diagnose. Personally, I would get to a good indy shop to validate diagnosis and suggested remedy before making that substantial investment of replacement or loss from selling as is.

[Karmic Man]

From my experience, regular motor hesitation and cylinder misfiring on a mild tune like yours will eventually lead to a motor rebuild. Some sooner and some later.

If one has to play around with plugs and gapping on a low mileage stock motor with a stock turbo to reduce misfiring and hesitation, it's time to sell the car if it has been modded.

Cheapest way out is to get your local trusted mechanic to rebuild the motor or at least fix it to a point that it's driveable without codes and trade it in.

[Poochie]

Originally Posted by NBE23M2

I didn't give them any other information other than what I was doing when it happened and what came up on the idrive display.

So how did they specifically know about the 'Dinan Tune'?

You had a piggyback installed, you remove it, reset the adaptions - and voila; like magic, it never exist, without a trace.. 🤷🏻

Proof:

https://www.bimmerpost.com/forums/sh...php?p=21988588

https://www.bimmerpost.com/forums/sh...php?p=21991389

The way you describe your timeline of events, you stated that you removed the Dinan Sport and then when with a BM3 flash tune. Did I miss something?

[chmura]

Originally Posted by AndrewC1989

Not to be an ass but it's stories like this that make me 100% content with my stock tune

Me too, but my stock M2c is kind of slow to me already. Have owned it for almost 2 years already. I'm getting the itch!!

[KevM2]

Originally Posted by F87source

OP a few things I want to add:

1) Did you data log your car after flashing the ots map for the first time and after the first misfire was addressed, if so can you post it?

This is an essential part to ensuring your car or local fuel quality can handle the map without issue.


2) Why didn't you half the maintenance interval? BMW is notorious for having extremely long maintenance intervals which contributes to premature failure after warranty. This shouldn't have been an issue for such a low mileage car though, just some advice I suppose.


3) What were the exact misfire codes and were the from bm3, ista, or a generic obd2 tool? Also did any of the spark plug electrode fall off into the cylinder?


4) It is kind of weird that the engine failed from a misfire, generally at such low power levels misfires tend to be benign.


5) Did you use anti-seize on your plugs?


6) I would not advise in buying any used n55 engine and dumping it in the car and selling it. If you do not have the proper paper work proving that the used engine was in good shape and an m2 engine you will loose insane resale value since bmw already inspected it and now it will be on the car fax reports.


7) What I recommend is filing a claim through your car insurance, if you have comprehensive coverage that will count towards engine replacements. Your premiums will jump but I think the end cost will be less than doing a proper m2 engine replacement.

Wide band o2 sensors are not needed on BMW's because the factory sensor is already wide band and can provide all the data required through the obd2 port, unlike most Japanese cars which use narrow band sensors making it a requirement to have those gauges. So no need to waste money one an AFR gauge and wide band sensor.

Yes that is exactly what he could have done.

Is it a bad idea to use anti-seize? Are you implying some of it could've fallen into the cylinder?

[F87source]

Originally Posted by KevM2

Is it a bad idea to use anti-seize? Are you implying some of it could've fallen into the cylinder?

Yeah it is not good to use anti-seize, bmw specifies no additional lubes or products are to be applied to the spark plug threads.

The reason behind this could be:

1) Anti-seize affects torque values leading to too much torque which could damage threads on the plug or cylinder head (unlikely unless you also have a off torque wrench and are really tightening the crap outta the plug)

2) Not exactly like you said unless you use a ridiculous amount. If you put too much anti seize on the plug it could get on the tip and the metal in the anti-seize can cause misfires. This is why most plug companies and car manufacturers also say not to use anti-seize.

I'm not sure why people even use anti-seize, because the spark plug hole is supposed to be relatively clean and rust free. Unless the owner uses high pressure water to wash the engine bay, but even then most heads now a days are aluminium which should be ok with water.


Here is a source as well:
https://www.tomorrowstechnician.com/...er%2Dtightened.

[GoneIn4Secs]

Can you describe what is meant by the motor 'hesitation?

Like you floor it and you dont feel thr torque until a few seconds later? Isn't thst just turbo lag?

[GoneIn4Secs]

Originally Posted by Got f1?

I don't disagree. I have spent my mod dollars on suspension, brakes (pads), wheels and some aero to make the most of the power I have. It would still be helpful to learn from this and establish a solid guess on cause. I have an M2C, so that has its own issues, but knowledge would be a good thing.

Seems to me there is more to know from OP to potentially diagnose. Personally, I would get to a good indy shop to validate diagnosis and suggested remedy before making that substantial investment of replacement or loss from selling as is.

Yes with s55 i would feel like your walkin on eggshells too, but you have good stock power anyway

[Poochie]

New short block:


https://parts.bmwnorthwest.com/p/BMW...002412514.html



Used wholesalers:


https://www.sharperedgeengines.com/r...bmw-m2-engines

[F87source]

if the short block is ok (no holes in it, and no major scoring on the cylinder walls) then it would be cheapest to just rebuild the short block. Around $5K, maybe a bit more if machining is required.

[Megator]

Originally Posted by F87source

Also I don't believe the flash counter is everything, there are probably other mechanisms the car can use to detect tunes, like boost deviation in comparison to fueling for piggy backs. Or hidden ghost codes for flash tunes. There is even data stored on the key.

100% this, the ECU records if the engine over boosted = boost/TQ target changed = changed ECU.

[F87source]

You know I keep thinking about this and something does not add up, especially since bm3 makes absolutely fantastic ots maps and op's m2 is really low mileage.

1) are you sure you flashed the correct map?
2) where are your data logs? If you do not have any at all, that likely is the problem. No data logs and running an ots map blind = huge Chance of blown motor.
3) how was your hpfp performing? It could have been your hpfp being super weak or you had a bad hpfp that couldn't meet the pressure demands resulting in low fuel rail pressure and therefore a misfire. This is the most common cause of a misfire on the F series n55 that I can think of, factoring in that all your other parts are in good working order.

Again data logs are needed...

4) did you press the coil tab all the way down? And ensure the connector was plugged in properly?

A little bit more info would be nice op, we are all trying to help you out in diagnosing this issue and point you in the cheapest path for repair.

[ewant81]

Originally Posted by NBE23M2

To be clear, the car never had a Dinan software tune in it. Only the Dinan piggyback harness and that was removed almost immediately. The engine failed while using stage 1 93 octane OTS Bootmod3 tuning software and NGK plugs.

The plug tips and electrodes were never physically hit by anything and the OBD code read “P0301 Cylinder 1 misfire detected”.

To be honest I don’t know what the hell happened. I can tell you that I will not be using OTS maps again on any BMW. That’s on me for sure but I wonder if something else happened. I guess we’ll never know for sure.

I’ve spoken with a local BMW shop in Cincinnati who has done some other minor work on my vehicle (springs and body parts) and they basically said try to find a used engine since they don’t specialize in engine rebuilds. They also mentioned it may be quite difficult to locate one and even if I do find one there is no warranty.

Part of me wants to call the bank and tell them to come and get it and pay them the difference but I’m not sure that will work well for my credit score.

Maybe an LS7 swap. Haha.

All kidding aside, if you’re running an OTS Bootmod3 tune I would highly suggest logging some data to make sure it checks out ok.

That might've been me mistakening your original post regarding the Dinan tune.

I've had first hand experience of excessive det on a previous engine that was probably a consequence of the fuel-pump having degraded with age and led to running lean at high load+revs. But the symptoms of misfire and then loss of compressions does sound very familiar. In my case part of the piston crown melted and bounced around the combustion chamber before exiting through the exhaust.

IMO it's ok to tune a car as long as you understand the consequences to your warranty (and also you insurance as some will void if they figure out the car has been modified and not recorded with them, although this might be a UK thing only).

Personally I wouldn't use something that modified the engine mapping without having first run some logs, or getting it onto some rollers, to check that the AFR, timing, and knock-sensor aren't doing stupid things.

In terms of car tuning, breaking your engine is a kind of right of passage! It might be expensive but you learn a lot from it

[SeanWRT]

What made the dealership go as far as check with Dinan for coverage?

Something doesn't feel right.

[NBE23M2]

Originally Posted by GoneIn4Secs

Can you describe what is meant by the motor 'hesitation?

Like you floor it and you dont feel thr torque until a few seconds later? Isn't thst just turbo lag?

No not turbo lag feeling. More like when the suspension hits a bump but instead it’s the engine. I would describe it as missing.

[nioh_lbbm2]

this is why datalogging is important. Gas quality varies so much region to region.

[Pray for Mojo]

Sorry for your luck.

Where's the datalogs? I really hope this wasn't another flash and full send situation.

The fact the car was knocking when you hammered it in a roll makes me think you had LSPI and probably some knocking up top. If you don't verify the fuel quality in your area you are just asking for problems.

[F87source]

Originally Posted by Pray for Mojo

Sorry for your luck.

Where's the datalogs? I really hope this wasn't another flash and full send situation.

The fact the car was knocking when you hammered it in a roll makes me think you had LSPI and probably some knocking up top. If you don't verify the fuel quality in your area you are just asking for problems.

OP has no logs, which is unfortunate but not much we can do at this point.

Just remember to do logs even with a custom dyno tune op, gas quality changes frequently.

But the thing is it's weird that the ecu hasn't adapted to the crappy fuel quality and pushed a softer timing curve. Normally bmw ecus are really good at combating knock.

[AmuroRay]

Low mileage M2 engine, $5,000 - https://car-part.com/cgi-bin/search.cgi

[nothingman]

Maybe you guys aren't aware, but the latest version of ISTA (4.24.x) now auto flags cars with "aftermarket software" without any manual intervention. I have seen at least two instances of this being reported. One on the instances was on the F80 forum and then the thread mysteriously disappeared. The other I saw the other day by this person (not me) in a Reddit group:

[pz619]

Suggest you take it to an independent place that specializes in BMWs. The dealer MO is to simply replace everything, which is probably why your quote is so high.