M-Class (W163) Produced 1998-2005: ML 230, ML 320, ML 350, ML 400 CDI, ML 430, ML 500, ML 270 CDI

Help: Rough Idle Engine is cold or cold start

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Old Oct 5, 2018 | 08:28 PM
  #1  
jay4usc's Avatar
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From: Lakewood, Ca
2001 ML 320
Help: Rough Idle Engine is cold or cold start

I'm hoping someone here can help me because this becoming a headache.

My car has been idling rough when the engine is cold. The rough idling only happens when I'm at the stop light when i first use the car but when i take off it runs smooth. If i put the car on park the idle is normal so it only happens when its on drive and when the engine is cold. When the engine gets warm (temp hits 80) the rough idle disappears and functioning normal. This started to happen last November when my battery died. Let me give you guys brief history:

2001 ML 320 93k miles. I'm the second owner and purchased the car when it had 83k miles 3 years ago.

Since I started to have this problem, I have replaced the following parts:

1. Fuel Filter (3 months ago)
2. Vacuum hose (2 months ago)
3. Crankshaft Position sensor (1 day ago)
4. Spark Plugs and Wires (5 months ago)
5. Fixed crack catalytic converter
6. MAF Sensor

I did bring the car to Indy Shop who is a certified MB technician when it first started to happen and he said ti could be a variety of things and he advise me to wait until i get a check engine light. A month later the check engine did light up and brought it to the shop and the mechanic ran a diagnostic test (charged me $110). He said I have a vacuum leak and he replaced the vacuum hose back of my engine. He also Advice me that I should replace the MAF Sensor soon and I did that myself. He said give a few weeks and it should start to run smoother. Well since then, my Crankshaft Position Sensor went out so i replaced that yesterday. Now today the idle seems to be rougher than usual and truly frustrated me. Maybe the computers are still setting since I just replaced the CPS yesterday. So after replacing everything the mechanic has advice and I'm still getting the rough idle, there has to be something else wrong. Although I don't have the check engine light on, I wanted to check what is stored so I went to Oreilly to get a reading. Below are the codes that showed up:

1. C1401
2. C1314
3. C1140
5. P0335
6. P2034

Please note: I have not seen the lights turn on for ABS, ETS, BAS, ESP since my battery died. So they only turned on when my battery died and unsure why they are still showing up. I already replaced the CPS but those codes are also still there. Should I be worried with these codes although the cel lights are not turning on?

I truly want to solve this idle issue so i can sell the car. I can't sell it like this. Hopefully someone here can help me. I have tried looking everyone on the web and very few have the same symptoms but no answers or resolution.

thanks guys,

Jeff



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Old Oct 6, 2018 | 08:27 AM
  #2  
Maj. Dundee's Avatar
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Joined: Oct 2011
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From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
The "C" codes {Traction Control) will have nothing to do with rough eng. running. Is your Check Eng. Light on presently?

All of the "C" codes were set because of the dead battery.

Codes P0335 & P2034 are the same and refer to the Crank. Pos. Sensor. Were all the codes deleted with a scanner?

Stop paying everyone to read your codes and get your own
scanner scanner
.

Where did you get the sensor from and who installed it?
Reply
Old Oct 6, 2018 | 12:40 PM
  #3  
jay4usc's Avatar
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Joined: Oct 2018
Posts: 76
Likes: 13
From: Lakewood, Ca
2001 ML 320
Originally Posted by Maj. Dundee
The "C" codes {Traction Control) will have nothing to do with rough eng. running. Is your Check Eng. Light on presently?

All of the "C" codes were set because of the dead battery.

Codes P0335 & P2034 are the same and refer to the Crank. Pos. Sensor. Were all the codes deleted with a scanner?

Stop paying everyone to read your codes and get your own scanner.

Where did you get the sensor from and who installed it?

no codes have been deleted for CPS sensor.
i bought the sensor from amazon see link below of my purchase.

Since i I have not deleted my code for the CPS will that hinder the function of the new sensor?

https://www.amazon.com/gp/aw/d/B001COAS78/ref=ya_aw_od_pi?ie=UTF8&psc=1 https://www.amazon.com/gp/aw/d/B001COAS78/ref=ya_aw_od_pi?ie=UTF8&psc=1

thanks
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Old Oct 6, 2018 | 12:41 PM
  #4  
jay4usc's Avatar
Thread Starter
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5 Year Member
 
Joined: Oct 2018
Posts: 76
Likes: 13
From: Lakewood, Ca
2001 ML 320
Originally Posted by Maj. Dundee
The "C" codes {Traction Control) will have nothing to do with rough eng. running. Is your Check Eng. Light on presently?

All of the "C" codes were set because of the dead battery.

Codes P0335 & P2034 are the same and refer to the Crank. Pos. Sensor. Were all the codes deleted with a scanner?

Stop paying everyone to read your codes and get your own scanner.

Where did you get the sensor from and who installed it?

my Check Engine Light is NOT on.
Reply
Old Oct 6, 2018 | 12:50 PM
  #5  
jay4usc's Avatar
Thread Starter
Member
5 Year Member
 
Joined: Oct 2018
Posts: 76
Likes: 13
From: Lakewood, Ca
2001 ML 320
Originally Posted by Maj. Dundee
The "C" codes {Traction Control) will have nothing to do with rough eng. running. Is your Check Eng. Light on presently?

All of the "C" codes were set because of the dead battery.

Codes P0335 & P2034 are the same and refer to the Crank. Pos. Sensor. Were all the codes deleted with a scanner?

Stop paying everyone to read your codes and get your own scanner.

Where did you get the sensor from and who installed it?
i installed the sensor myself.
Reply

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