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e320 wagon
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Discussion Starter #1
My car was diagnosed with a bad Mass air sensor after check light had appeared. I replaced the mass air sensor myself, after trying to clean the original with no success. Now that it has a new one it still continues to stall. Once you shut off the car and/or when it stalls while driving, it takes anywhere from 15 to 30 minutes to restart. Check engine light is no longer on but the problem is. I NEED HELP. Somebody, anybody please offer some insight.
 

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My Two Left Feet
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this may be a dumb q's but have you tried taking it off again and putting it back on?
 

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03 E320 4M Wagon & 97 E320
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If it stalls when hot and it won't start hot (but will start cold or cool), 95% of the time is your CPS (Crank Position Sensor).
 

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e320 wagon
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Discussion Starter #5
Thanks For The Info, I'll Try To Find The Cps Sensor Or Can You Tell Me Where It's Located? Thanks Again For The Much Needed Help...
 

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03 E320 4M Wagon & 97 E320
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Chris Tavares said:
Thanks For The Info, I'll Try To Find The Cps Sensor Or Can You Tell Me Where It's Located? Thanks Again For The Much Needed Help...
You did not tell us what exact car you have. E-class could have different engines in it, depending on the year. Different engines have CPS in different locations.

If you have the M112 engine, do a search of CPS and you can find many posts.
 

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Loubapache,
So what is it about the sensor that makes it fail hot? Does the magnetism fall off? Mine is suspect (have the fault code) but it has electrical continuity. Is there a rough test on magnetism, e.g. how many grams of steel should it support, as a test weight?
Bruce
 

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1999 E320, 1975 450SEL, 1979 280SE
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Hi, there are so many threads going here that it's hard to figure where to place this. But, this seems like the best place, at this time. I recently purchased a very nice, '99 E320. 61k miles. Runs great. But today, my wife drove it to Sears to get something. When she tried to start the car, after about 20 mins., she says that it would start when she turned the key but immediately stall when she let go of the key. The car did this 6 or 8 times before it finally stayed running and she could drive home. We have started it several times since, and it does fine. Does this sound like one of those sensors is going out? I have looked at previous threads and many refer to the CPS. No check engine sign is on, etc. Thanks for any comments.
Peter
 

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e320 wagon
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Discussion Starter #9
All Is Well Now!!!

:thumbsup: Just Want To Thank Loubapache And Everyone Else For Their Input On The Cps Sensor. I Even Managed To Save $30 On The Part At The Dealer...... Great Site And Good To Know You Guys Are Out There.
 

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Oo == oO 98 E320
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Hey Chris, how about putting in the year of your wagon as that can make a difference on answering questions. Also, where in TN are you?
 

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6.4.15//1535hrsMT 1998 MB E430/3rd owner/135,000mi//
After reading several sites over the last year, reports refer to multiple causes of the no-start & stall-while-driving problem;
(I have both) but, no definite fix-all solution has surfaced. The problem involves many years and models according the posts that I've read and Mercedes has yet to post a recall. Have read about several accidents caused by the abrupt stall. I survived a few high-speed stalls (between 40-70mph); the engine quits and fortunately, have been able to dodge traffic and restart in neutral on the fly. I don't have the answer; have experienced the problem for 5 years beginning around 120,000mi (I average 2,000 miles/year).

So far, over the last 3 years, have replaced/repaired/tested CPS, MAF, plugs, wires, vacuum hoses, fuse boxes, wiring harness, harmonic balancer, tensioner, retuned, K40 module, DIS module, coil primary&secondary resistances, control unit
fuse, ECU, fuel pump relay, overcharge protection relay, ignition lock freeze, neutral safety sensor/switch, vibration
damper, solenoid, idle air control valve, idle pin slide, rear differential speed sensor, ME controller to the CPS, camshaft
position sensor (distinct from the crankshaft position sensor), spark fuel pressure injector pulse, transmission mis-shifting,
cold start valve, engine temp sensor, fuel tank intake, and have run several professional diagnostic scans which show "no error codes." The problem persists. I'm not saying that some of these repairs won't fix other cars, they just haven't
fixed mine, yet. The loss of confidence and the unpredictable nature of the problem is grounds for continued
stress....when will it happen again ? If I can't rely on it, I will sell it or donate it, with a precaution. Shame that
Mercedes isn't taking an active role to identify the problem.

When restarting, dash lights may or may not light; check engine may or may not light. After a few minutes of switching, the car starts as normal, no error code appears. Next, I'm replacing the ignition switch next week, another cited cause.
This is a serious long term, multiple model 'defect'. I've reported my incidents to safercar.gov and MBUSA; who thanked me for my concern. I recommend that everyone who has this 'defect' email NHTSA and MBUSA to catalyze an investigation. Apparently there are so few reported incidents that the problem has been ignored.

Be safe and Good Luck ! Indy in Colorado.
 
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