[empire0]

Hey everyone. So i'm looking at buying an 09 M3, I tested it today (amazing car), and have a price set. My question is about the best route to make sure the car is up to snuff and there's no issues. Should I take it to the BMW dealer and have them run a diagnostic test just to be safe? What would that cost? The car is from a private dealer that specializes in imports, but I definitely want to make sure there are no hidden issues that might cost money down the road.

[pbonsalb]

If it makes you feel better, do it, but the shop may not be able to tell you how your rod bearings are doing or how much longer your throttle actuators will last. I would try to get any dealer service records and subsequent independent shop records so you know what has been done.

[empire0]

I know the throttle actuators have not been done, and i'm not even going to get into the RB issue, as it seems overblown. I'll make sure the oil has been done at regular intervals and was the proper type for the car.

[pbonsalb]

Its the rod bearings I would worry about most. I changed mine when my extended warranty ran out at 6 years. Had 60k miles and copper showing at the parting lines and down the sides, with significant wear in the main part of some bearings though none to the copper yet in that area.

The rest of the issues I have read about or experienced since I bought 6-7 years ago would not potentially destroy the motor. My car has actually been really reliable and most of these cars seem to be reliable thus far in their lives (they are all getting older now and the experience of the guy who owned one from age 3-10 years may differ from the guy who owned one from age 9-16 years). In 83k miles, I have had one throttle actuator fail, one fuel pressure sensor fail, motor mounts collapse by maybe 3/8 inch so I replaced them, front strut tension bushings wear to the point of clunking so I replaced them, and my front brake rotors will be done soon. I have done a lot of preventative maintenance and some handling and performance mods.

[Ashwanless]

Check the service history as mentioned. Also, plug in a cheap OBD reader if you can to see if it's had codes recently reset or pending.

Enjoy!

[Locloud9]

Originally Posted by empire0

Hey everyone. So i'm looking at buying an 09 M3, I tested it today (amazing car), and have a price set. My question is about the best route to make sure the car is up to snuff and there's no issues. Should I take it to the BMW dealer and have them run a diagnostic test just to be safe? What would that cost? The car is from a private dealer that specializes in imports, but I definitely want to make sure there are no hidden issues that might cost money down the road.

There are a million opinions on this subject. The bottom line is, are you going to be happy with it? If you stress too much over the "possible" issues, it might hamper your enjoyment. To curtail the "possible" issues, you have two options:
1) Buy a premium coverage warranty. There are several threads that talk about the various warranties people have gotten to ensure the TB's and RB's are covered.
2) Have ~$5k in the bank drawing interest. If one or both items fail, you can afford to pay for it. If neither fail, at least you're collecting interest.

Most of all, get the PPI done, and if it clears the PPI, buy it with confidence, and enjoy the hell out of it.

[empire0]

Thanks for the tips guys. It's getting inspected at BMW tomorrow, and if everything is good, it should be mine. It only has 78k KM on it, so it's not quite in the range for throttle actuators or RBs yet.

[pbonsalb]

There is no certainty range for either. But TA failure won't damage your motor so wait until you have symptoms. Unfortunately rod bearing failures will damage your motor and there aren't any reliable symptoms, though the failure rate still seem to be very low percentage of cars.