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xchudyxpl 11-14-2012 02:07 PM

Engine fail safe
Hi, guys

Here is the story in the nut shell. Today I replaced MAF sensor on my 2002 530i with the cheap aftermarket part ($30). After the replacement SAS light went out. After driving couple of times everything was fine until ENGINE FAIL SAFE appeared and cars throttle was not responsive at all.

Here are my thoughts:
I know that electrical parts should be OEM (times are hard wanted to save money)
The engine fail safe went off after I restarted the car.

My prediction is that the new aftermarket MAF sensor is throwing off the computer and causing this mess.

Please advise, I still have the original MAF sensor which I can put pack any time.
Is there any danger with having aftermarket MAF sensor installed?

Please advise.


Psalm11_6 11-14-2012 02:14 PM

Out of curiousity, which brand did you go with on the MAF?

I would say it's unlikely that you're going to cause lasting damage simply by cheaping out on this particular sensor. It CAN (and likely will) adversely effect the performance as the MAF is used to help determine air/fuel mixture ratio. I don't have any experience with janky MAF's, but I'd imagine there's a high probability of running either richer or leaner than expected, either way resulting in some overall oddities (depending on HOW rich or lean it gets).

xchudyxpl 11-14-2012 02:23 PM

There is no brand I purchased the sensor form e-buy (Chinese of course).
When it comes to engine fail safe, it never happened to me before. With that being said this happening in the same day when I changed the sensor seems a little odd. That's the reason I started the conversation in order to get some feed back.
Possibly share of similar sympthoms.

xchudyxpl 11-14-2012 03:17 PM

Any ideas guys?

moots 11-14-2012 03:29 PM

try putting back the original maf sensor and see if the sas comes back and engine fail safe goes away......if they do then it's the crappy $30 sensor.....

xchudyxpl 11-14-2012 03:37 PM

I will see what happens tomorrow. My only concern is while the cheap MAF sensor is installed can it cause any damage to the electrical system or what not?

moots 11-14-2012 05:14 PM

well that is anybody's guess.i'd rather be safe than sorry....

xchudyxpl 11-15-2012 04:39 PM

Here is the update, the engine fail safe did not come back however, the check engine came back (assuming the $30 sensor is a piece of junk)
Will put the original back during the weekend and see what happens.
Again, I do not have any air leaks my only assumption is that MAF sensor is bad.

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