Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

2006 BMW 525i (N52) possible wide spread defect

hchihchi Posts: 8
edited March 9 in BMW
This is the message I sent BMWNA 2 days ago. They have still not responded by email or telephone. Are there any other owners out there with low miles that had problems with their timing chains? I'll be contacting the BBB shortly and I assume this might be one of those hidden defects that the company does not want others to know.

I had a recent problem with our 525i. I was driving it and it lost power/died. The car would not restart and no error lights or messages were displayed on the IDrive. I had the car towed home. After the initial check of the vehicle, it showed the crank sensor fault. I noticed a bunch of metal throw off in the oil filter and the vehicle did not have compression in cylinder 2 and 6. I was thinking catastrophic engine failure.

Since I am very familiar with American/Japanese vehicles, I decided to look into the problem myself after getting no response from BMWNA. The car is out of warranty with 85K miles.

The metal throw off was due to the timing chain jumping off of the exhaust cam gear and grinding against the back of it. The cause of the problem was the two aluminum screws under the cam shaft gears. Both heads were broken off and one made its way up the chain getting caught in the chain and gear. These screws are aluminum. I don’t know if this is a common problem but for the bolts to break it would be due over torqued/tighten bolts or extreme pressure from expanding/contracting of the magnesium vs aluminum. I suspect over tightening. The other broken bolt head is still some where in the bottom of the oil pan. The exhaust cam gear was chewed up, but still serviceable. I re-timed the car and checked the compression. I got lucky and compression is good so no bent valves. I disassemble everything and now I patiently waiting for several parts. However, I'm still dealing with the broken head that is some where in the oil pan.

I re-contacted BMWNA and the customer service rep took down some information and stated there was nothing they could or would do for me. She noted my concerns to better service future customers and advised me to take the vehicle to the dealer. I asked to speak to some else and she stated she was only in customer service and no one there could assist me. I'm a bit surprised, because I have always had excellent dealings with BMW. I recall a time when BMWNA representative personally called me to rectify a warranty issue. The dealer did not want to cover the item under CPO. A person from corporate assisted me and earned my loyalty. This is the reason why we currently own 3 BMWs (05 325XI, 06 525i, and 07 335i). I understand car maintenance is a must, but when something is not the fault of the owner should I have to bear the entire cost of the repair. I’m not asking for anything other than consideration or a return call from anyone who has the authority assist me.


H. Chi


  • hchihchi Posts: 8
    Still no response from BMWNA and I will be filling with NHSTA and BBB to have them look into this problem. :lemon:
  • H. Chi --- Did BMW ever respond? If so, I would like to learn what the result was. I have the same problem.

    I have a 2006 530 with the N52 engine. Last year, I had a severe oil leak in the front of the engine. The BMW dealer took a look and discovered a broken cylinder head bolt near the oil filter. The estimate to repair (a complete head gasket replacement) was about $3500. After being turned down for an out-of-warranty repair, I took a stab at replacing the broken bolt myself. That fixed the oil leak.

    Fast forward to today - - I was replacing my valve cover gasket (another small oil leak) and noticed that there were three other bolts broken off in the same manner as the first one. Turns out there are 4 aluminum bolts that hold the front of the cylinder head to the block (around the valve train galley). One is external; the other three are under the valve cover.

    I plan to contact BMWNA on Monday and would like to know if you has any luck.

  • hchihchi Posts: 8
    BMW wanted me to take it to a BMW dealer at my expense. They stated the service writer and their machanic would have to inspect it and then it coulkd be determined if it "might" be covered. However BMW wanted $1500 to look at it and (thousands) to repair it. Better bolts need to be made. They should be made with a steel core like several bolts that the N52 motor has on the outside holding the wire harness. Yes, 4 bolts are included in the replacement kit and 3 of my the heads sheared off. It is clearly a manufactures defect and I would advise you to file with NHSTA and the BBB. If enough others file, BMW might actually be obligated to do something!!! Maybe I can get re-imbursed the cost of my repairs!!! ;)

    I have completed the repairs and the car is fine. I ended up spending about $2,000 for specialty tools, parts, and a scanner. Others who are not so mechanic will have to spend a lot more. Let me know if you need any other assistance, but BMWNA was a waste!!!!!!!!!!!!!!!!!!!!!!!!!! :lemon:
  • hchihchi Posts: 8
    The aluminum bolts are stretch bolts. They are torqued to a specific amount and turned an additional 90 to 180 degrees to properly torque/stretch the bolts. The N52 aluminum head boats required another 90 degrees after the torque values. (BMW repair recommendation) I did not stretch my bolts and I think they were 15 or 10 nms??? About 88 inch pound of torque if I remember correctly. I never recovered one on the sheared aluminum heads and it is still caught up some where in the oil pan. Good Luck
  • I started with the local BMW dealer and got confirmation that THIS IS A KNOWN PROBLEM with N52 engines. Next I connected with customer service at BMW North America. I worked my way up from first level customer service rep to manager --- same result --- acknowledged that this is a known problem. BMW will cover repairs if under warranty or, in some cases, will cover under "customer goodwill" if recently out of warranty.

    Here is my gripe; BMW knows that this is a design problem (versus a maintenance issue) but refuses to repair. If repaired at a BMW dealer shop, it is a $3,000 to $4,000 repair. OUCH!!
  • hchihchi Posts: 8
    My car was out of warranty and I purchased the car new. I did not buy the extended warranty. I was about 25,000 miles over and when I called BMWNA, they stated there was not much they would do. If I had the CPO warranty or if I was close to the 40K warranty??? Who knows. A known defect, but bmw refusses to repair or correct it. I find it a little disturbing that they would not recall the problem. I guess 50K buyers are small fish. Are they going to repair it for you at no cost?? Good luck and let me know what happens.
  • Update - completed repairs a couple weeks ago. Like you, I had to "invest" about $2,000 in parts, speciality tools, etc. Based on BMW dealer estimate, this was about half the cost of dealer repair. All 4 aluminum head bolts were broken off -- the heads popped off. I dismantled the valve chain guide and other parts in search of the bolt heads, however, no luck. I suspect they are in the oil pan. However, I do not have the ability to remove front frame section and lift engine to pull the oil pan! What a pain! Before this, I would have recommended BMW to others, but not now. My ownership experience with Mercedes Benz was much better. I suppose this kind of issue also fuels the recent Audi sales pitch. On the bright side, I am now discussing options with an investigative legal firm.
  • hchihchi Posts: 8
    edited December 2011
    Some legal firm did contact me about a class action law suit. If there is enough people maybe BMWNA will take some action. I looked at a new 5 series, but I am a little concerned about some of BMW's shady business practices about known defects and soft recalls! :confuse:

    Now you have experience as I do to do your own repairs. Glad you got it running!!!
  • Today I found out the my 2006 525I bolt head is missing. Funny thing is I just had the car in for service in August and was in service 6 weeks before that. And none of the service people mentioned that it could be a possibility or checked it. My warranty just expired Oct 2011 in august they never said nothing to me. I told the man this is a scam. A car that was sold over 30 or even 25K that is less than 7 years old should not have broken metal bolts. Bolts are suppose to be strong. I am driving the thinking this thing is going to fall apart. I have had all kind of things repaired on this car. I want to speak to a lawyer.
  • Like alot of people, we find out after our warranty is over that our head bolts have broken. how Convenient is that. After reading the blog. I think BMW is pulling a scam and perhaps that is why they discounted the model but did not inform the public that the bolts are faulty.
  • Please let me know the law firm's name.
  • rwmckrwmck Posts: 2
    I have an '06 530i and I was just told i have the same problem. i've contacted BMWNA and am escalating currently. any updates from earlier posts?
  • We got our 'bad news' from the BMW service dept. in Sept. 2011 for our 2006 BMW 525i sedan. Same problem, the bolts were sheared and 'probably in the engine' (as we were told) No assistance was offered. Our radiator was also leaking so bad that it was 'undrivable' as is... We are in the letter-writing stage. Has anyone had any luck with contacting the 'right people' at BMW corporate?
  • hchihchi Posts: 8
    I have had no luck with BMWUSA and I was contacted by some law firm that wanted me to join in some type of law suit. I decided not to persue it. My neighbor is a mechanic and he told BMW has some class action law suit against them. It was about their failure to recall known defects. I have not confirmed this. I got my car running and it cost me 2k and 3 days of work. The car has been fine since I repaired it. The only other problem we had was oil leaks for all three BMWS. I recently took care of those myself as well. BMW wanted $450-500. It cost me $20 in gaskets and 3-4 hours per vehicle. (oil filter housing leak) :D
  • I had this repaired recently costing about $3600. Originally, the dealer wanted $6200 with a lot of unnecessary part replacements. The use of Aluminum bolts in the magnesium alloy casing seems to be a design defect which BMW is not owning up to. I called BMWNA also to see if this was a recall issue---nope. This is my first BMW (most japanese prior) and I may not get another one. If anyone is planning a class action, I am in.
  • Unfortunately, I've done quite a bit of research on the legality of not telling a consumer that a car has had previous repairs to fix a defect or mechanical problem. The automotive industry has a powerful lobby in D.C. because although "unethical" this is not "illegal". Actually, the automotive industry has managed to sneak under legal radar on almost everything regarding the purchase and servicing of autos.
  • pilcheespilchees Posts: 3
    I have a broken cylinder head bolt on a 2006 530xi. There are 80,000 miles on the car and the BMW warranty had just run out. BMW will not cover it, nor will the brand new aftermarket warranty I just purchased. There seems to be much discussion about this defect. If anyone can tell me what to do, I would appreciate it. Happy to join a lawsuit if one exists. BMWNA was no help, nor was the dealer.
  • rwmckrwmck Posts: 2
    bmw was very cool with me. after much prodding, they agreed to cover the repair in its entirety. the local dealer was going to cover 1/2 and i'd pay the other, but because the local dealer was supportive bmwna covered the whole thing. i had a good relationship with my service adviser and between his pushing and my 2-3 calls a week to bmwna, i'm a happy customer. good luck!
  • I have a 2006 530 and have now replaced the head bolts twice, once @ 55K and today @ 105K miles and paid about $2200.+ each time and out of warranty. So much for high performance. I am thinking that corporate BMW has a problem that they don't want to own up to. This is not acceptable.
  • bmwoesbmwoes Posts: 1
    I have been experiencing problems with the computer system on my 2013 BMW 5 series. The navigation system shuts off in the middle of a trip. The car doesn't recognize the music on my iPod. I can't search music on my blue tooth connected iPhone. Periodically the car can't locate my remote key in my pocket so the car won't start. The presets for the radio stations will disappear. Has anyone experienced any of these problems?
Sign In or Register to comment.