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2002 ML320
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32 Posts
Discussion Starter #1
Hello
My '02 ML320 has developed this fault recently. It would take 3 or 4 tries before the engine starts then the warning light will stay on for a day or so. Then it goes out by itself. This happened 3 times over the last month. I did a search but couldn't find something directly similar to this. Found a few threads about the warning lights and its relation to the increased exhaust emmissions but nothing about the engine not starting
The car is not due for service yet. It has 118,000 klms on the clock

Thanks in advance
Raf
 

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Dallas, Texas
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7,758 Posts
Have codes read from engine control module. Check engine light comes on indicating other problems not necessarily emissions related. Transmission may request Check Engine light. In your case it is most likely crankshaft position sensor. Since you have model 2002 code for crank sensor will remain stored.
 

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2002 ML320
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32 Posts
Discussion Starter #3
Is this it below? I disconnected the wiring to take the picture

If so, anyway of testing it before I replace it?
Thanks
 

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1999 E55, 2001 E320, 1990 560 SEC, 2004 ML350, 2001 ML55, 1995 S500, 1998 SL500, 2010 E550 Sport zoo
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7,035 Posts
Yes - good photo and you can cross reference to the photo below:

Google Image Result for http://www.marcusfitzhugh.com/CLK/DIY/photos/cps2.jpg

A word to the wise mate, you need the genuine Bosch brand replacement part and NOT a no name or private brand China made equivalent. The Bosch here in the States goes for like USD$42, the China names are sold for USD$20 and actually here in the US some retail auto parts stores sell the China no name for $45 (and some even say, oh yeah, its made by Bosch - no it isn't).

The no name or private label sensors are real-real bad quality, most don't even work right out of the box.

There have been one or two guys who reportedly used MAF cleaner (which does not leave a residue) to clean the metal sensor that said that worked OK, but never heard from them again.

Bust out your dollars, this part isn't that pricey, really, and does tend to wear out about 100K miles or so.

Keep the faith !
 

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Dallas, Texas
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You can look at oscilloscope trace, check voltage output or check resistance. Problem is you have to catch it in failed state which is usually with engine hot. Reading codes is much easier.:)
 

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2002 ML320
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32 Posts
Discussion Starter #6
It stalled in the middle of a busy traffic light today. Might aswell take it to the dealer to replace it this week. Can't afford the car hosing itself when my wife is driving it with a screaming 3.5 years old in the back seat
Booked it for Wednesday, will report back the errors then
 

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02 ML320 06 ML500
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It stalled in the middle of a busy traffic light today. Might aswell take it to the dealer to replace it this week. Can't afford the car hosing itself when my wife is driving it with a screaming 3.5 years old in the back seat
Booked it for Wednesday, will report back the errors then
This is at most a 15 min. job. Why haven't you considered doing it yourself?
 

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2000 ML320
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74 Posts
You can look at oscilloscope trace, check voltage output or check resistance. Problem is you have to catch it in failed state which is usually with engine hot. Reading codes is much easier.:)

What he said ^^

I don't have access to a scope but I checked voltage and resistance when I was having the same stalling/no start issues you described. Problem was, both times it died on me on the road I had it towed back to my house, by the time it got back it would run and start fine and the sensor would pass resistance and voltage tests. I couldn't get the damn thing to replicate what it was doing while I had my multimeter. Unfortunately for me mine never threw a check engine code either, I just ended up replacing the CPS on an educated guess. It did fix my problem. I would consider doing it yourself if you can, I know my dealer charges $350 to replace it. It's really easy to do, I'm new to working on cars myself and I did it in a half hour with no lift.
 

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2002 ML320
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Discussion Starter #9
I could've done it but didn't want to mess with the car because my wife uses it all the time. Also I don't have the code reader nor I will be able to clear it anyway
$250 later and it is fixed. Here is a copy of the error codeif it helps someone else
Rafik

 
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