Many times over we've seen newcomers post with questions regarding what to look for when purchasing a 1-Series for the first time. My goal, with the support of other 1ADDICTS, is to make this thread the ultimate "one stop shop" for first time buyers. I'm not all knowing, so if I get something wrong PLEASE CORRECT ME, or if I miss something, call it out!
As of today (7/18/16) this thread is BRAND NEW and ...
UPDATE 7/19/16: I'm already getting great info from fellow members, keep at it!
UPDATE (2) 7/19/16: Officially stickied, praise to the Mods!
UPDATE (3) 7/19/16: Holy formatting Batman. I think I've got everything up to date, will update if we get more info.
UPDATE 7/21/16: More info added from member suggestions, added amazon links for some tools, added aftermarket parts/mod sites.
UPDATE 7/21/16: Featured on www.Bimmerpost.com!! 
Looking for info on N51 engine if anyone can offer it!
I'm counting on current members to help me populate this thread!
I'll continue to update this post as more people reply with helpful information, citing those who contribute.
If you're here, it's most likely because you're considering buying a 128i or 135i. The goal of this thread is to help you make an informed decision and become a happy BMW 1-Series owner for years to come.
First things first; we're not here to tell you whether the 128 or 135 is better for you, or that it's better than another car on the market,
that's up to you to decide.
Also check out
The Ultimate Aftermarket Warranty Review: I lay it all out with invoices, detailed numbers, and other goodies to help you decided if a warranty is right for you, and if you can afford to own a 1-Series!
So let's get started!
The first BMW 1 Series started production in 2004 with the E87, and was first brought to the US as 2008 models with the E82 (Coupe) and E88 (Convertible/Cabriolet) which started production in 2007. The most major revision year was 2011, which brought a new engine to the 135i as well as some interior and exterior changes. 2012 cars also saw a facelift, with new lights, and some changes to the interior and iDrive systems. In 2013 the 135is model was introduced and produced in very limited numbers. NOTE that some pre-2013 cars were marked as "135is" on their VIN-build sheets, this is not accurate, only 2013 cars are actually capable of being the 'is' model, we are not sure why it's listed on some earlier build sheets. 2013 was sadly the last year the 1-Series was produced, and they have now been replaced by the new 2-Series.
We'll focus on the E82 and E88 128i for now, keep scrolling down for info on the 135i.
2008-2013 E82 and E88 128i:
Specifications:- Power: 230BHP and 200 lb-ft of Torque
- Engine: 3.0L 6-Cyl N52 (Naturally Aspirated)
- MPG: Rated at 18city/28hwy
- Curb Weight: 3,252 to 3,494 lbs depending on options
- Transmissions Offered: 6 Speed Auto and 6 Speed Manual
MOST common issues with the 128i and N52 engine (what to look out for):
- Valve Cover Gasket Leaking/Valve Cover Cracking. Symptoms include: Oil all around valve cover, spark plug threads oily
- Electric Water Pump Failure - Symptoms include: Car goes into limp mode, recommended to be replaced at 60k+ miles
- Thermostat
- Oil Filter Housing Gasket (OFHG) Failure - Symptoms include: Oil leak on front of engine around filter housing, losing oil over time, oil pooling on ground under car or on skid cover. Replace gasket for fix ($300-$900+ depending on shop, DIY possible for mech-inclined individuals)
- Windshield Washer Tank Leak - Symptoms include: Fluid runs low often, pool of fluid under car after filling tank. (Potential DIY?)
2008-2013 128i/N52 Maintenance Notes/Requirements/Parts:
- Engine oil: ~6-7qts of BMW LL-01 Oil (honorable mention: Castrol 0w-40 euro blend)
- Oil filter: Mann-Filter HU 816 X
- Manual transmission: 2qts of GL-4 fluid (honorable mentions: Redline MTL, Redline D6 ATF)
- Differential (manual trans) 1qt of GL-5 75w-90 fluid (honorable mention: Redline 75w90)
- Spark plugs: NGK LZFR6AP11GS, NGK 6619 LFR6AIX-11
- Air filter: Mann Filter C 27 114
- Cabin air filter: Mann-Filter CUK 8430
- Power steering fluid (CHECK YOUR RESEVOIR CAP) but most likely 1 liter of Pentosin CHF-11S
DOT4 brake fluid
- Coolant: 1gal BMW coolant + 1gal distilled water, mixed 50/50
- Spark Plugs for the 128i are shown as NGK LZFR6AP11GS on RealOEM and NGK's catalog. (These are 95712.)
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2008-2010 E82 and E88 135i:
Specifications:- Rated Power: 300BHP and 300 lb-ft of Torque
- Engine: 3.0L 6-Cyl N54 (Twin-Turbocharged)
- Rated MPG: Rated at 18city/25hwy
- Curb Weight: 3,373 to 3,660 lbs depending on options
- Transmissions Offered: 6 Speed Auto and 6 Speed Manual
2011-2013 E82 and E88 135i:
Specifications:- Rated Power: 300BHP and 300 lb-ft of Torque
- Engine: 3.0L 6-Cyl N55 (Single, Twin-Scroll Turbocharger)
- Rated MPG: Rated at 18city/25hwy
- Curb Weight: 3,373 to 3,660 lbs depending on options
- Transmissions Offered: 7 Speed Dual-Clutch Automatic and 6 Speed Manual
MOST common issues with the 135i N54 & N55 engine (what to look out for):
- (N54) Turbo Wastegate Rattle - Sypmtoms include: Rattling noise from front end especially at idle.
- (N54 & N55) High Pressure Fuel Pump Failure
- (N54 & N55) Electric Water Pump Failure - Symptoms include: Car goes into limp mode, recommended to be replaced at 60k+ miles
- (N54) Carbon Buildup/Deposits on Valves - Symptoms include: Rough idle, decreased performance. Walnut blast for fix ($300-$600 depending on shop/location)
- (N54 & N55) Oil Filter Housing Gasket (OFHG) Failure - Symptoms include: Oil leak on front of engine around filter housing, losing oil over time, oil pooling on ground under car or on skid cover. Replace gasket for fix ($300-$900+ depending on shop, DIY possible for mech-inclined individuals)
- (N54 & N55) Windshield Washer Tank Leak - Symptoms include: Fluid runs low often, pool of fluid under car after filling tank. (Potential DIY?)
2008-2013 135i/N54&N55 Maintenance Notes/Requirements/Parts:
- N55 has Valvetronic, N54 does not
- N54 uses problematic piezo injectors and the N55 uses lower cost solenoid injectors (if someone could provide part #'s for N54/N55 that would be awesome)
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Research Resources:
Things to look for when buying a used car, not necessarily specific to 1er's or BMW:
- Rust! Check the body panels around creases, underneath wheel wells/arches, and check the frame/underbody.
- Oil! Check the oil if possible, an oil analysis is best case scenario and can be done on the cheap.
- Coolant - coolant should be one color and clear, if there's white mush/chunks, or if it looks thick, run!
- Modifications - typically the fewer the better, unless you know the previous owner, try to get a stock (no mods) car.
- Excessive wear - does the interior/exterior look like it has more "miles" than what's showing on the odometer? This could be a sign of abuse on the car.
- Vehicle history report - often offered for free now, it's a great way to get some information on the car's history. HOWEVER it is NOT a complete history, and only shows what is reported to insurance. An accident not reported will remain hidden from the report.
- Alignment - simple but important, if the wheel is tilted heavily to the left or right while going straight, this could be an indication of a past accident.
- Mismatched paint/components - does a body panel look slightly different from the rest? Is one headlight noticably clearer than the other? All signs of a potential accident and should be investigated.
Recommended Tools for the Do-It-Yourself owners!- THE 1ADDICTS SEARCH TOOL!! Seriously, this forum has enough information to hurt your brain.
- Carly App or other code reader, Carly also allows cool coding features to unlock your car's potential features
- 3/8" metric hex bit set
- 3/8" Male & female Torx set
- Flexible 1/4" and 3/8" extensions
- Extensions of all shapes and sizes (1/4", 3/8", long & short)
- Universal joint socket connectors
- BMW jack stand adapters (or just cut some wood to stuff into the jack points)
- Quality torque wrench
- Metric offset box wrench set
- Oil Filter tool (Any Volvo/BMW 86mm/16 flute one will work)
- Skinny Spark Plug Socket
ALL CARS Recommended Maintenance Intervals (Note that your car will also keep track):
- Antifreeze: 60K
- Brake fluid: 24K or every 2 years
- Rear Differential fluid: 50K
- Spark plugs: 80K
- Manual gearbox fluid: 50K
- Oil change: 5K
- Power steering fluid: 24K or every 2 years
Other ALL CARS Notes:
- Owners Manual and lots of great videos from BMW (this link is for 2011 135i, there are other pages for other years)
- Amazing site with tons of DIY vids
- The Bluetooth functionality in these cars is widely regarded as awful. Especially in the case of Android owners like myself, do not expect it to work right.
- The general consensus for reliability is as follows: 128i > 2011+ 135i > 2008-10 135i
- Parts can be EXPENSIVE. Just because you can afford to BUY the car does not mean you can afford to OWN it.
- Whether or not an Extended Warranty is worth it or not is pretty subjective and your results will vary on the car and your own maintenance/driving tendencies.
- If you buy a 135i and tune it, it is highly recommended to get a stronger charge pipe, as they are known to fail under increased boost.
- You should only run Shell 93 Octane - anything else is for peasants
Recommended Sites for OE Parts:
Recommended Sites for Aftermarket Parts & Mods:
Contributing Shout-Outs! Huge thanks to all of those who helped develop this post:
desertman123 (this guy is on a roll!) Added: A ton of N52 common issues, Recommended DIY Tools, 128i Maintenance Requirements, maintenance intervals, BT issue details, more recommended tools
1and1 Added: Carly App and injector details, RockAuto as parts supply, skinny spark plug socket
tock172 Added: Washer tank clarification, N55 vs N54 injectors and valvetronic
gjm120 Added: 128i Spark plug part #'s
davis449 Corrected me on the single turbo, should be listed as Twin-Scroll
Gray_Panther Added: BT issues for 128's
Dackelone Added: PDF's upon PDF's upon PDF's!