[Joebie]

I'm writing this from the inside of the tow truck, so I'll probably be brief I'll update lots more later.

Anyways as the title states, I was going for a pass and accidentally dropped my 2011 n52 into 2nd gear instead of 4th like I wanted to and let the clutch out. The car abviously revved way too high. By my math, about 9200rpm. There were no harsh noises beyond that. The car lost power and I pulled over. I let it sit for a minute and tried to start it again but it wouldn't even turn over.

There was no oil underneath the car or anything.

I'm thinking maybe it skipped timing, but I'm not really sure where to start troubleshooting. I'm thinking a compression test but how do I do one if it doesn't turn over?

I'm pretty sure it needs a new engine, do I just skip the troubleshooting phase and get a used engine on order or is there some due diligence I need to do before I call the engine totalled?

Any other advice on what to do next? Thanks in advance.

Any good source on where to find a good used engine?

And yes I know I'm an idiot. Been driving stick for 15 years and this is a new one for me. Not a mistake I'll repeat.

[Joebie]

Okay so I took out the spark plugs and took off the accessory belt and spun the engine by hand with a socket on the crank and it actually spins freely, with the exception of maybe a few spots that its a bit harder to turn, but its not like its hitting a hard stop (like a valve) or anything like that. The "harder" spots happen exactly 6 times every 2 revs, so its gotta be valvetrain related. Maybe springs.

I think my next move is a compression test. My brother has a tester, I don't, so I'll have to wait to do that. I'm going over to his house tomorrow for Christmas so I'll grab it then.

I'll keep this thread updated as I figure out more stuff in case anyone else in the future is dumb enough to do the same thing as me. Merry Christmas to me I guess. Shit.

DOES ANYONE KNOW WHY MY CAR'S ENGINE WOULDNT TURN OVER ON THE SIDE OF THE ROAD WHEN I TRIED STARTING IT, BUT TURNS OVER JUST FINE BY HAND IN MY GARAGE? Does the ECU know that it just revved past 9k rpm and just wont let me start it anymore because of that?

Anyways, next steps are

-compression test (I think I'm looking for around 200-220psi, the spark plug is an M14 x 1.25 for the compression tester adapter)
-borescope to look for evidence of valve/piston contact



Is there a procedure for checking timing on the N52? I'm assuming there's a mark on the flywheel I gotta line up somehow to get TDC and then some marks on the cam? Is this in the Bentley somewhere? (EDIT: the timing check procedure is on section 117-17 of the Bentley)

[desertman123]

are you sure those "hard" spots aren't just the compression stroke

[Joebie]

Originally Posted by desertman123

are you sure those "hard" spots aren't just the compression stroke

I have the spark plugs out so yes I'm sure.


I've made a graph depicting the effort to turn vs crank degrees to better explain.





Here's my spark plugs, cyl 1 on the left to 6 on the right. I don't think this is valuable info in any way but I took a pic anyways.

[Phyrexia]

Sorry to hear about your luck.

I think you broke your timing chain.

[Joebie]

Originally Posted by Phyrexia

Sorry to hear about your luck.

I think you broke your timing chain.

I guess that's possible, but if I broke my timing chain then at least one of the cylinders would have the valves open and i should feel it hit as i try to rotate my crank, which I don't.

Eventually I may pull the valve cover and take a look for anything out of place under there, including the timing chain.

[Joebie]

I scanned the car and below are the results.

Also strange is that when i sat down to scan, the battery light came on on my dash, which I've never seen before. What confuses me is that I don't see any correlation between over-revving my engine and my battery light coming on so that's weird... I think some of these codes are due to my low battery.

[Biginboca]

Looks like 2a9a might indicate a broken or skipped timing chain

[Phyrexia]

Maybe i'm misinterpreting your graph, but to me it's depicting increased difficulty due to interference with valves in one cylinder.

Originally Posted by Joester

I guess that's possible, but if I broke my timing chain then at least one of the cylinders would have the valves open and i should feel it hit as i try to rotate my crank, which I don't.

Eventually I may pull the valve cover and take a look for anything out of place under there, including the timing chain.

[Phyrexia]

Originally Posted by Biginboca

Looks like 2a9a might indicate a broken or skipped timing chain

Yeah he's got Camshaft Not Aligned With Crank, Intake Vanos Confused, and Exhaust Vanos confused.

Definitely seems like you need to get it on a charger and pull the valve cover.

[Joebie]

Originally Posted by Phyrexia

Yeah he's got Camshaft Not Aligned With Crank, Intake Vanos Confused, and Exhaust Vanos confused.

Definitely seems like you need to get it on a charger and pull the valve cover.

Thanks for the input everyone. My next steps, in order, are

-put battery on trickle charger
-compression test
-pull valve cover, check timing alignment
-borescope to look for valve/piston contact evidence


If I see evidence of valve/piston contact or if it fails compression check I'm pretty sure I'm just going to buy a used engine for it. There's a few on car-part for $1000-$1500 with low mileage.


Does anyone know what engines are compatible with my 2011 N52 328i without having to do a bunch of coding shit? I'd like a direct swap if possible. Does the N52 from a 128i work? Does the N52 from a 128i have any different components on it like oil pan or sensors or anything? I think I need an engine thats newer than 2009 if I want to avoid potential lifter tick, thats when they updated the head, right?


I still have family stuff to do today so I can't dig in today, but I'm having a couple of friends over tomorrow so we can probably find out a lot more then.


Thank you all so much for taking the time to reply with your thoughts, I'm going to get this damn thing fixed one way or another I love this car too much to let it die like this. I kept it so perfect in every way up until now.

[Taskmaster]

Originally Posted by Joester

Thanks for the input everyone. My next steps, in order, are

-put battery on trickle charger
-compression test
-pull valve cover, check timing alignment
-borescope to look for valve/piston contact evidence


If I see evidence of valve/piston contact or if it fails compression check I'm pretty sure I'm just going to buy a used engine for it. There's a few on car-part for $1000-$1500 with low mileage.


Does anyone know what engines are compatible with my 2011 N52 328i without having to do a bunch of coding shit? I'd like a direct swap if possible. Does the N52 from a 128i work? Does the N52 from a 128i have any different components on it like oil pan or sensors or anything? I think I need an engine thats newer than 2009 if I want to avoid potential lifter tick, thats when they updated the head, right?


I still have family stuff to do today so I can't dig in today, but I'm having a couple of friends over tomorrow so we can probably find out a lot more then.


Thank you all so much for taking the time to reply with your thoughts, I'm going to get this damn thing fixed one way or another I love this car too much to let it die like this. I kept it so perfect in every way up until now.

Should be all the same, swap the over the sensors though.

[Joebie]

Alright fellas well the compression test came back around 110-120 psi across all cylinders which in itself isn't SUPER concerning (although a bit lower than i expected, even on a cold engine).


So we got out the $4 amazon borescope and every cylinder had clear marks and gouges on top of the piston where the valve contacted. I'm sure that the valves floated and couldn't close fast enough and collided. I'm suspicious, but not sure, that the timing slipped as well.





We put it all back together and for shits and giggles tried starting it. It wouldn't even try to start except once it showed a sign of life for a second and it sounded like a diesel.

Since new motors are cheap as hell, out she came. Had a few friends over and she was out in about 5 hours. Mad props to my friends, it would've taken 5 days instead of hours if it was just me.





Next steps

-find donor engine
-replace oil pan gasket, valve cover gasket, and oil filter housing gasket on the stand
-swap over any sensors I might need to
-reinstall engine with new water pump and t-stat (I was at 102k miles anyways)


Things I'm thinking about replacing but I'm not sure about just yet... what do you guys think?
-clutch/flywheel
-starter
-crank pos sensor
-engine mounts

[Biginboca]

Wow that is a ton of progress, nice work!

If you can swing it financially the clutch and flywheel is a no brainer to me to do now. All the other things are still easy to get to when the engine is in place. I would probably do the engine mounts now also though just cause they are cheap.

[Joebie]

Originally Posted by Biginboca

Wow that is a ton of progress, nice work!

If you can swing it financially the clutch and flywheel is a no brainer to me to do now. All the other things are still easy to get to when the engine is in place. I would probably do the engine mounts now also though just cause they are cheap.

Thanks! I was pleasantly suprised at how much we knocked out, too!

Do you know what the "common" clutch replacement for the 328i? Do people just use OEM stuff, or is a SMF conversion usually done with aftermarket stuff? What are the good clutch brands?

I thought engine mounts were expensive? Maybe that's the 335i I'm thinking of?

[Taskmaster]

Originally Posted by Joester

Alright fellas well the compression test came back around 110-120 psi across all cylinders which in itself isn't SUPER concerning (although a bit lower than i expected, even on a cold engine).


So we got out the $4 amazon borescope and every cylinder had clear marks and gouges on top of the piston where the valve contacted. I'm sure that the valves floated and couldn't close fast enough and collided. I'm suspicious, but not sure, that the timing slipped as well.





We put it all back together and for shits and giggles tried starting it. It wouldn't even try to start except once it showed a sign of life for a second and it sounded like a diesel.

Since new motors are cheap as hell, out she came. Had a few friends over and she was out in about 5 hours. Mad props to my friends, it would've taken 5 days instead of hours if it was just me.





Next steps

-find donor engine
-replace oil pan gasket, valve cover gasket, and oil filter housing gasket on the stand
-swap over any sensors I might need to
-reinstall engine with new water pump and t-stat (I was at 102k miles anyways)


Things I'm thinking about replacing but I'm not sure about just yet... what do you guys think?
-clutch/flywheel
-starter
-crank pos sensor
-engine mounts

I literally have all of that for sale (water pump, thermostat, clutch and flywheel)- brand new, PM me!

[rjahl]

It would be interesting to learn the peak RPM reached. I think Hassmachine mentioned the DME stores that value and it can be easily read.

[desertman123]

Originally Posted by Joester

I have the spark plugs out so yes I'm sure.

My b I didn't see if you had the plugs out or not

Great work on yanking the motor out quickly!

[Joebie]

Originally Posted by rjahl

It would be interesting to learn the peak RPM reached. I think Hassmachine mentioned the DME stores that value and it can be easily read.

I'd be very interested too but I've never set up INPA or whatever software I need for that.

[hassmaschine]

that was fast! I did something similar, but I clutched in pretty quickly, I don't think it went past ~8200rpm. no damage (it was a couple years ago already).

I don't know if I have the address for the over-rev counter for your specific model (I can find it if needed), but you can install BMW tools from a bunch of different places (just look in the coding forum). Then you can use INPA to read the RAM address for 'n_h_max', which can be converted from RPM to hex (sure would be cool to add that to Bimmergeek's ProTool).

I'll try to do it on my car, I'm curious because I've forgotten all about it until just now.

[Phyrexia]

Sorry to hear about your pistons. Think you'll end up pulling the valve cover for us, for Science, to check on the condition of the timing chain? It would be pretty easy at this point.

[Joebie]

Originally Posted by Phyrexia

Sorry to hear about your pistons. Think you'll end up pulling the valve cover for us, for Science, to check on the condition of the timing chain? It would be pretty easy at this point.

I'm eventually going to make a coffee table out of the engine block so yeah, ill take some pics. Anything in particular you wanna see besides the chain?