1994 BMW 325 6 cyl Two Wheel Drive Manual 170000 miles
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My car usually drives well. But randomly it stalls w/ light showing real quick. Sometimes, the engine just dies without any stalling or hesitating while I am still driving i.e. 40m/h without speed changes. Most time, I have to wait to start again. It won't start right away. All the electrical functions still work, even if the engine goes off.

Here are some suspect things. My car has soft-top and got wet last winter due to overflows from top-container. So water overflowed into bottom of the car. At the same time, I found the main power cable and the power cable to computer were damaged. So my mechanic fixed popped section of the cables. Since that, the problems started happening. After I dried my car under sunlight w/blow drier, the problems were gone for a while. About 3 weeks ago, I saw check engine light on. The code said 1221, which was oxygen sensor. And this is a key thing: I was stupid. I sprayed carb cleaner through air mass meter. The check engine light was gone. Everything looked fine. Two days later it stalled and died randomly. Somebody said it would damage the sensor. I went to mechanics, and he said examined values of air mass meter was 8; values should be between 8 and 20. I have changed oxygen sensor. Still no light. Working good for 2 days. The problems popped up again.

I remember the symptoms have been very similar since first happening.
So, could you give me some answers, even clues what is going on my car? I really appreciate your time and advice.

At that age and mileage, I would check fuel pressure and delivery. Fuel pumps fail and you might be at the point where replacement is warranted. Also replace the main and fuel pump relays at this time.

Thank you for your response. BTW could you tell me how to replace them? I have no idea where they are. If you can, can you link any useful websites or web-pages?? Thank you again.

The fuel pump is inside the fuel tank and can be accessed by removing the rear seat base (it snaps into place) there are 2 panels, it's the one on the right side. As far as the main and fuel pump relays, they are adjacent to the fuse box which is under hood and is on the left side close to the fire wall. The relays are under a rectangular black plastic cover, there are three relays, two of them will be orange and one will be white (or green) The main relay has 5 prongs and the fuel pump relay will have 4. As far as a printed manual for your car,I highly recommend Bentley publications and they are available from Amazon.com or perhaps online, there is also Mitchell manuals available through the 2carpros website.

I found my relays and pump, etc. But can you tell me how to check they are actually bad? I think my ABS relays are bad, because I hear click from the ABS and feel vibration from brake pedal. Please tell me how to check the relays are bad.

As a rule, I just replace them, checking them is difficult due to the intermittent nature of the failure. As to the ABS issue, seek out a local BMW technician to assist you with the brake issue, safety issues are best left to trained BMW knowledgeable professionals. Are the brakes worn out and do you have warped rotors?

oaky I changed MAF and test-drove. I don't experience engine died. But my car stalled a little bit with instant check engine right? Do you think it is fuel filter or crankshaft sensor???

It seems as if you have your own agenda and are not a listening for my advice. As my dad says "Due to the numerous complaints about the free service, it has been discontinued"

oh i am sorry that I didnt mention a few things. I have checked relays and they were okay (according to general diagnosis). And I have changed MAF due to advice from my mechanic. So I was asking that I should spend more money to change other parts. I am sorry for bothering you. Your advice was awesome, and I have no doubt about your favors. Thank you very much.