187K miles 2008 E93 M3 6MT needs some help

Hi everyone,

I bought a middle-aged crisis toy for myself with the intention of restoring it, maybe not to M539 level, but somewhere close. I am willing to learn, can wrenching, but need some mentoring on BMW. The car has some codes, and leaks, what a surprise hah..To prevent me from throwing money where it is not required at this point, I need some help to identify what needs to be done to delete the CEL and the codes below. The car starts up well, but I can hear an “exhaust leak” sound for the first few seconds, and then it idling normal. Tachometer needle is pretty steady, maybe very rearly it goes down for a millimeter once. The shop I sent it to for PPI said that - Check engine light on. «Performed short test and found fault codes 00278A- DME catalytic converter
conversion bank 2, 002789- DME catalytic converter conversion bank 1, 0027B0- DME secondary air
system flow rate Bank 1, 0027C7- DME O2 sensor trim control adaptation bank 2, 002B58- DME idle
controller monitoring. Suspect an issue with the secondary air pump, with the higher mileage this could also be a sign of excessive blow by/crankcase pressure in the engine.»

Questions:
- Are E92 and E93 struts and shocks the same? Can I put a suspension from E92?
- Which store is better Bimmerworld or FCP Euro? Or maybe something else?
- Anyone from Cincy/Dayton/Columbus area?

Anyway, any help would be highly appreciated! Let me know if I need to add any other info.

P.S. The car was bought on Cars and Bids for 12.7K

First thing - get a scanner. I use a Carly and love it. Second, if the battery is older than 3 yrs old, just get a new one. I don't care how well it tests out. I've experienced way too many misbehaving modules over the years that work perfect with a new battery. Enjoy your new ride!

alekseikosarev wrote

Questions:
- Are E92 and E93 struts and shocks the same? Can I put a suspension from E92?
- Which store is better Bimmerworld or FCP Euro? Or maybe something else?
- Anyone from Cincy/Dayton/Columbus area?

Answers:
- The E92 and E93 use different struts. This is because of the weight difference between the two chassis. I assume the same is true for the rear shocks.
Struts and shocks from an E92 should not be used on an E93.
- FCP Euro provides a lifetime warranty on the parts it sells.
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See images of E93 and E92 strut part numbers with details.
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If the exhaust noise you’re hearing for the first few minutes of startup is not the secondary air injection system, check all of your header to x-pipe crush gaskets. Leaks there will give cat inefficiency codes and kill o2 sensors. Check all the grounds, especially the one near the driver side header.

M3BatMobile wrote

First thing - get a scanner. I use a Carly and love it. Second, if the battery is older than 3 yrs old, just get a new one. I don't care how well it tests out. I've experienced way too many misbehaving modules over the years that work perfect with a new battery. Enjoy your new ride!

Bought Foxwell NT530 Plus, still learning how to fully use it, but was able to clear all codes. Have driven for about 50 miles, so far no codes have popped up. Thank you, will check the battery.

spammysammich wrote

If the exhaust noise you’re hearing for the first few minutes of startup is not the secondary air injection system, check all of your header to x-pipe crush gaskets. Leaks there will give cat inefficiency codes and kill o2 sensors. Check all the grounds, especially the one near the driver side header.

Plan to work on the underneath sometime soon and will be covering - driveshaft middle bearing, flex disk, manual shifter rebuild, diff pin seal, and exhaust leaks/issues.

Another thought. Set up a dual project list. One of critical fixes/ evaluations that require a mechanic and a DIY path of some fun low cost projects that are pretty cheap. Such as interior lightbulb replacement, red start button, red Mbutton monitor EBay for some interior trims and panels you can pick up real cheap and install yourself. If the car is a long term hold - I’d save the new wheels, air intakes, brakes and exhaust for after you get the engine, electronics and drive train sorted out.

Welcome and you will love driving this with the top down. I picked up my 2012 E93 in Nov. 2025, same "middle-aged" boat as you. Wanted a fun car to drive around in and it has not disappointed.

My 2011 (I’m original owner) has 205k on it. She was my daily driver for over 10 yrs. Now I put her to pasture and restoring her subframe and all

spammysammich wrote

If the exhaust noise you’re hearing for the first few minutes of startup is not the secondary air injection system, check all of your header to x-pipe crush gaskets. Leaks there will give cat inefficiency codes and kill o2 sensors. Check all the grounds, especially the one near the driver side header.

alekseikosarev I second this emotion and advice from spammysammich. Any leaks at all from the Exhaust header donut gaskets will cause rough idle even when the engine is warmed up and those leaks cause the O2 sensors to throw codes. Also air leaks in the secondary air pump system (underneath the air box plenum at the firewall end) will also cause codes due to the vacuum leak. Check for cracked or loose hoses at the hose clips etc. During the first 90 seconds (I think) of cold start operation the air pump operates which makes the cold start idle a little louder than normal and also a little more "lumpy". Good luck with the big list of maintenance items. Let us know how it all goes.
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https://www.realoem.com/bmw/enUS/showparts?id=WL93-USA-08-2008-E93-BMW-M3&diagId=11_4132
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M3BatMobile wrote

Another thought. Set up a dual project list. One of critical fixes/ evaluations that require a mechanic and a DIY path of some fun low cost projects that are pretty cheap. Such as interior lightbulb replacement, red start button, red Mbutton monitor EBay for some interior trims and panels you can pick up real cheap and install yourself. If the car is a long term hold - I’d save the new wheels, air intakes, brakes and exhaust for after you get the engine, electronics and drive train sorted out.

You have read my mind - I already found so many used interior/exterior parts on eBay, but haven’t pulled the trigger because, like you said, I want to make sure the drivetrain is good first, then suspension, and then take care of the interior/exterior. My car is from GA and I guess was stored outside, so the interior is in rough condition as to top seals. I am planning to do LCI multimedia and possibly NBT (found a couple of treats on the Russian drive2.ru website), replace subs to Bavsound, paint/wrap all soft-touch plastic, and restore the leather parts. Basically, my goal is to restore it to OEM+ - everything wihat make sense upgrading I am planning to do.

M3BatMobile wrote

My 2011 (I’m original owner) has 205k on it. She was my daily driver for over 10 yrs. Now I put her to pasture and restoring her subframe and all

Wow, you’ve given me hope for at least another 20,000 miles!🙂You definitely have a great eye for color combinations. 👍

First of all, thank you to everyone who chimed in. The suggestions and expertise are genuinely motivating, and a lot of it turned out to be right on the money.

Oil consumption: After driving the car “properly” for about 500 miles — meaning all the way to 8400 rpm almost all the time — the consumption has stopped. The level indicator has been stalled dead center on OK ever since. I have a theory about why, but I’ll save it for the comments.

The battery: Someone in the thread mentioned low voltage. Dug a charger out of my toolbox, put it on the battery overnight, cleared everything the next day, drove 20–30 minutes, and the codes never came back. Free fix.

Then last week: Misfire, limp mode, P0300 through P0304, in the parking lot of the local donut place. I assumed this was my punishment for buying a dozen donuts. Limped home, dug into it, and after coils/plugs the next most likely cause was O2 sensors — which lined up with the 0027C7 O2 trim adaptation bank 2 code from the PPI, plus the bank 2 O2 stuff I’d been seeing on and off. I’d already picked up a used set off eBay, so today I replaced all four.
Oh boy. Car drives like it dropped 100K off the odometer. Throttle response, pull, idle — different animal.

As of today: zero codes. No cat conversion codes (00278A / 002789), no secondary air (0027B0), no idle controller (002B58). All I’ve done is four O2 sensors and a top-off of washer fluid. Never touched the cats or the secondary air pump.

More to come.

alekseikosarev wrote

First of all, thank you to everyone who chimed in. The suggestions and expertise are genuinely motivating, and a lot of it turned out to be right on the money.

Oil consumption: After driving the car “properly” for about 500 miles — meaning all the way to 8400 rpm almost all the time — the consumption has stopped. The level indicator has been stalled dead center on OK ever since. I have a theory about why, but I’ll save it for the comments.

The battery: Someone in the thread mentioned low voltage. Dug a charger out of my toolbox, put it on the battery overnight, cleared everything the next day, drove 20–30 minutes, and the codes never came back. Free fix.

Then last week: Misfire, limp mode, P0300 through P0304, in the parking lot of the local donut place. I assumed this was my punishment for buying a dozen donuts. Limped home, dug into it, and after coils/plugs the next most likely cause was O2 sensors — which lined up with the 0027C7 O2 trim adaptation bank 2 code from the PPI, plus the bank 2 O2 stuff I’d been seeing on and off. I’d already picked up a used set off eBay, so today I replaced all four.
Oh boy. Car drives like it dropped 100K off the odometer. Throttle response, pull, idle — different animal.

As of today: zero codes. No cat conversion codes (00278A / 002789), no secondary air (0027B0), no idle controller (002B58). All I’ve done is four O2 sensors and a top-off of washer fluid. Never touched the cats or the secondary air pump.

More to come.

Glad it's all working out for you. Given the mileage on the car, I recommend being proactive and using the best gas available to help preserve the fuel injectors. Various threads have been popping up on the forum documenting failed injectors. Shell V-Power was independently tested by AAA and documented to provide 19 better deposit protection as well as cleaning up to 100% of engine deposits. See attached report and links.
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https://www.shell.us/fuels-oils-and-coolants/shell-fuels/shell-v-power-nitro-premium-gasoline.html
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The best fuel around me is Top tier BP gas statio. Have been using so far, no issues.

Wow that is insane...12.7k for that??? So cheap...I really need to pick up one of these as a small project car to add to my E92 M3 and E90 M3 to round off the collection. Would love it in this Melbourne Red too. Great project ahead of you! This car would probably double that and then some in Germany.

Update: misfires are gone after the O2 sensors, but now I have a CEL for P2096 — post cat fuel trim too lean, bank 1. Current and pending. Clear it, drive ~20 miles, it’s back every time.

No P0171 or any upstream lean code, so the fueling loop looks fine at the head. That puts it between the pre-cat sensor and the rear sensor on bank 1 — same bank as the misfires were.

Going to swap the two rear sensors bank to bank first to rule out a dud new one. If it stays P2096, I’m calling it an exhaust leak and doing gaskets.

Anyone seen post-cat lean on one bank with no upstream lean codes turn out to be something other than a leak? Stock exhaust, ~188k.