[davidxF1]

Hey. I bought a 2008 BMW 335i from facebook marketplace on June 21st. Work done to it prior from buying was a Water pump replacement, Oil change, New tires, and new suspension. The lady I bought the car from claimed to be the 2nd owner and the only problems she stated was cosmetic. When seeing it in person I was never told of any other issues or problems with the car (obviously). When test driving for about 10-15 minutes everything worked and seemed fine. No CEL, No weird noises, no lights on the dash. I purchased the car cash for $8,000. The same day of purchase my Mom was driving to the DMV when the car showed it was overheating, CEL, and low coolant, as well as entering limp mode forcing her to pull over at a gas station. Today (June 28th) I was told by a mechanic the head gasket blew and the water pump was bad as well. I was told that the engine would most likely need to be pulled out and looked at but I was looking at around 6-7k for a replacement engine. Mechanic did not charge me for what he looked at and recommended I try selling it for what I can. There’s many other details to the story but it would be very long to include them all. The lady who sold the car does not want it back and instead is convinced I did something while driving. I’m 18 and knew the sacrifices I would have to make when purchasing the car but did not expect something this major, this fast. If I could get any recommendations on next steps or possible solutions, it would be extremely helpful. Thank you.

[lowrydr310]

Find a new mechanic.

If the car was running great when you bought it, it's not likely that it suffered catastrophic failure shortly after you drove it home.

Don't stress, find a reputable BMW mechanic to look at it.

The cooling systems have a lot of plastic that gets brittle with age. There are a few common failures on the N54 cooling system, do a little search on water pump housing cracks, radiator end cap leaks, radiator inlet leaks, Oil filter housing gasket leaks, and mickey mouse flange leaks. There are tons of YouTube videos that show you how to do all these repairs which you can save on labor, but even if you're not comfortable it's still reasonable to pay a mechanic, far better than trashing the car or replacing the engine unnecessarily.

That mechanic sounds like a clown if he didn't give you any evidence. Head gasket failures are extremely uncommon on n54s.

[TemjinX2]

I doubt you blew a headgasket. The headgasket on the n54 is very robust, you will blow up the motor before a headgasket.

Find a n54 mechanic. Working on n54 requires good knowledge of german style mechanics and understanding the canbus system.

You cant take it to a regular mechanic, they wont how know to fix it. Your mechanic is guessing without pulling any codes.

You can try joining a n54 fb group and ask someone locally to pull the codes for you or you can buy kcan cable and use mhd to pull the codes.

Wild guess is your water pump is broken, you can test your water pump by using the water pump bleeding process.

You can find the procedures on youtube

[Podunk]

you can test water pump functionality with the car off using the bleed procedure.

the mickey mouse flange is known to fail on these cars, and so logn as your mother pulled over and immediately shut the car off, it is unlikely you warped the head or block and had a head gasket failure.

if she kept driving ( like most females do for some reason i'll never understand.. i swear the $$ signs don't flash in their retinas when lights come on like most car enthusiast men do. that light comes on, limp mode and overheat, you pull over quick cause you just hear the "cha ching, cha ching, cha ching" and this is not BMW specific.. even LM7 LSx engines are getting pricey, and don't get me started on price of the 8.1L Vortec 492 in a 2500..)

Anyway without a block test, leak down test, or compression test to reference i wouldn't hang on the technicians words, and as for block test, you can buy the kit for about 50 USD from napa comes with the fluid and the little squeeze ball and tube, stick it on the reservoir tank with engine running and squeeze the ball if it turns from blue to green/gold, there's an issue.

you can also pressure test the cooling system for leaks, ( pressure tester is also cheaper than your mechanic labor rate) common failure points are the radiator and mickey mouse flange, as well as the seam on the expansion tank failing. the water pump snout and thermostat can crack and leak as well, but are less common.

if he is sayin head gasket cause there is oil in coolant, more then likely the failure is the oil filter housing gasket..which can be confirmed if the block test fluid stays blue.

good luck on your car, i also bought a pre LCI 2008 E90 335i, 185K on odo, bought it with 181K, mostly just done maintenance with upgrades. but engine is solid so far.

another thing, you can also get bimmergeeks software for reading codes and live data, it's about 150 USD for the master license, and works with the MHD CANBUS connector or the cheap amazon INPA obd2 connector, while not being limited to the DME only ( MHD is DME limited) . also works if you want to add features with BMW coding, but recommend you research before doing any feature coding.

[davidxF1]

UPDATE: I took in the car to a BMW specialized mechanic. I plan on doing all the upcoming work myself but I just moved to a new state and have 0 tools & this is also my daily so I wanted to be sure of the route cause. The main issue was the water pump. The previous owner replaced the water pump with aftermarket parts which were obviously not good enough to last not even 1,000 miles. The mechanic also mentioned an oil leak as well as some faulty turbo codes. Im getting the water pump changed today and when that’s done he will go further with testing. I will follow up with any further info but as far as the oil leak, he wants $1700. This seems a little steep but I also wasn’t told how significant the leak was. Is this something I can do myself or do you guys think I should just pay up that price. I appreciate all the help and specifics in your replies.
BTW for more specifics of the car it is a 2008, 93k Miles, Stock (no mods/upgrades).

[TemjinX2]

Originally Posted by davidxF1

UPDATE: I took in the car to a BMW specialized mechanic. I plan on doing all the upcoming work myself but I just moved to a new state and have 0 tools & this is also my daily so I wanted to be sure of the route cause. The main issue was the water pump. The previous owner replaced the water pump with aftermarket parts which were obviously not good enough to last not even 1,000 miles. The mechanic also mentioned an oil leak as well as some faulty turbo codes. Im getting the water pump changed today and when that’s done he will go further with testing. I will follow up with any further info but as far as the oil leak, he wants $1700. This seems a little steep but I also wasn’t told how significant the leak was. Is this something I can do myself or do you guys think I should just pay up that price. I appreciate all the help and specifics in your replies.
BTW for more specifics of the car it is a 2008, 93k Miles, Stock (no mods/upgrades).

I would pay him to do a full diagnosis of the car, with list of everything wrong.

Your 18, you have the time. Just buy the parts you need from fcpeuro and diy. Vehicular diy on youtube has very detailed n54 diys.

[lowrydr310]

Originally Posted by davidxF1

Im getting the water pump changed today and when that’s done he will go further with testing. I will follow up with any further info but as far as the oil leak, he wants $1700. This seems a little steep but I also wasn’t told how significant the leak was. Is this something I can do myself or do you guys think I should just pay up that price.

Did he say where the oil was leaking? Valve cover gasket? Oil filter housing gasket? Oil pan gasket?

For reference there's a shop in Southern California that posed some repair specials a while back. The prices likely increased since this was first posted, but gives you a rough idea of what to expect.

[Podunk]

depends on what is said to be leaking oil, the oil pan your suppose to remove the sub frame to do, but can get away with just lowering it. valve cover is about a 3 hour job if doing with plastic.. 5 hour if replacing with aluminum cause retorquing all the bolts as you go along is a pain, OFHG requires intake manifold to come loose and be moved, and at that point may as well do intake gaskets too.

if you learn to DIY the car is not expensive, because you save tons of money on labor. if you can't DIY, labor will be what eats you alive.

[jkline398]

Don't be scared away by this, you have a great car that needs very specific babysitting, but as everyone said these engines are extremely tough. My 2010 335i at 140k (30k of mine) has been a champ after fixing the dozen or more issues that went neglected by about 7 previous owners... do it right with the right shop (a good shop will tell you how to fix some problems yourself to save money) and change oil often, these cars will hold up.