C-Class (W202) 1995-2000: C 200 CDI, C 220 CDI, C 270 CDI, C 180, C 200 K,C 230 K, C 220, C230, C 280

Performance Drop by 20-30% What happaned

Old Feb 28, 2009 | 07:57 PM
  #1  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
Question Performance Drop by 20-30% What happaned

Hey all
I realized that some times my C280 '97 Sport drops its power tremenuosly. Ex when i stop at the lights and start movinbg again i have to step on the gas like 50% down to get 40mph by the middle of the block (high way road block say 900ft in total ~~) At the same time on the same road when i feel that car has power i can press gas ~10-15% down and get to 40mph in about 1/4 of the block. Also what I notices is when I dont press on gass and i'm going los speed say 20mph I feel like cars brakes are in use and i'm loosing seed too fast.

Maybe some one have any ideas? Car has 83k miles on it so it seams not too much for mercedes. Oh yea, if I go max speed and max throttle for new sec (say from ligh to light) and then geting back to normal driving it seams that car gets much more power aftter wards. hmmm

Another note.. when car is not moving and engine is idle i get sort of vibration es[pessially when there is an decline toward passanger side. but when i release the brake and start moving the vibration goes to relative zero.

Finally I took OBD mesurments (maybe they would be handy for experts)
I hve results in both parked and driving positions of transmission (in both cases car was standing still) below is my data:


C280 OBD2:

At Idle, Pared position
Absolute Trotle Position: 2.7%
Engine RPM: 694 r/min
Speed: 0
Calculated Load: 15.7%
Timing Advance (Cyl. #1): -9.0 Degree
Intake Mainfold Presure: 33kPa
Flow rate (MAF Sensor): 3.33 g/s
Fuel System 1 Status: closed loop
Short Term Fuel Trim (Bank 1) -0.8%
Long Term Fuel Trim (Bank 1) +3.9%
Intake Air Temperature: 37 C
Coolant Temperature: 93 C
O2 Sensor 1, Bank 1: 0.195 V @ +1.6% s.t. fuel trim
O2 Sensor 2, Bank 1: 0.480 V


Driving Position (Summer Mode) standing still:
Absolute Throttle Position: 3.5%
Engine RPM: 599 r/min
Speed: 0
Load: 20.8%
Timing Advance (Cyl. 1) -8.5 Degree
Intake Mainfold Presure: 39 kPa
Air Flow Rate (MAF sesnor) 3.61 g/s
Fuel System 1 Status: Closed Loop
I hope some one can tell me what it looks like. Maybe i'm just being paranoid ...
Thanks for help!

Reply
Old Feb 28, 2009 | 10:26 PM
  #2  
Untertürkheim's Avatar
MBWorld Fanatic!
 
Joined: Mar 2007
Posts: 2,408
Likes: 3
It seems strange that there would be so much load on the engine, is that normal?
Reply
Old Feb 28, 2009 | 10:29 PM
  #3  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
I cant say anything about load I dont remember old OBD2 readings... so maybe some one with share their load values on idle?

My new mech told me to use differenet oil 10W-30 instead of 10W-40 that MB reccomends. can that be a problem?

Reply
Old Feb 28, 2009 | 10:37 PM
  #4  
Untertürkheim's Avatar
MBWorld Fanatic!
 
Joined: Mar 2007
Posts: 2,408
Likes: 3
Originally Posted by alexus
I cant say anything about load I dont remember old OBD2 readings... so maybe some one with share their load values on idle?

My new mech told me to use differenet oil 10W-30 instead of 10W-40 that MB reccomends. can that be a problem?

Do not use 10w-30! Get a good 229.5 -40 weight oil like Valvoline Synpowr 5w-40, M1 0w-40 or Liquimoly 5w-40.

Is the engine reving with low power, or are the RPMs staying low?
Reply
Old Feb 28, 2009 | 10:45 PM
  #5  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
RPMs are fine (i think so at least) Tach goe to 20k then switches gears... same as in old days.

Just feels like i'm haveing 400 pounds in the trunk. Thing is tha its not the same, some times it works like i have 300 hp instead of my 145 hmm

Another thing is that engone wireing harnes that goes to (what thioese things called in English .. the once that prodie sparks for ignition) one of the wires seams to be either cut off and replaced (hopefully) or just cut off i think it should be relaced as OBD doesnt give any warnings so i assume all cylinders are fired up OK. I will have pix of that wire posted.

Whats a difference in oils
which part of oil means what. I know one is wiscosity and another um forgot.

How do i select oil? I dont want to "liquid" oil as it will leak. I have drain plug leakage .. i think all merces have that.
Reply
Old Mar 1, 2009 | 12:04 AM
  #6  
rondocap's Avatar
Super Member
 
Joined: Jul 2008
Posts: 769
Likes: 5
From: New York
Mercedes S55 AMG
I have a 2000 c280 sport with 90k miles...I notice this too. Sometimes it isn't as responsive on the throttle and acceleration, but other times it's really much faster. I always use 93 octane gas, and Mobil 5w40.

I don't know what it is, maybe the engine on these cars is just like that and not always consistent?
Reply
Old Mar 1, 2009 | 12:10 AM
  #7  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
so i guess its not only me
I will be stopping by Mercedes performance shop that does sports cars and tuning, I'll see what that would say.
Reply
Old Mar 1, 2009 | 01:59 PM
  #8  
rondocap's Avatar
Super Member
 
Joined: Jul 2008
Posts: 769
Likes: 5
From: New York
Mercedes S55 AMG
Yeah, let us know what they say - I want to know too. If it is something serious, we can fix it.
Reply
MB World Stories

The Best of Mercedes & AMG

story-0

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-1

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-2

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-3

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-4

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

 Verdad Gallardo
story-5

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

 Verdad Gallardo
story-6

Mercedes EQS Gets A Major Update: Everything You Need to Know

 Verdad Gallardo
story-7

5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

 Verdad Gallardo
story-8

Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

 Verdad Gallardo
story-9

10 Most Reliable Mercedes-Benz Models You Can Buy Used

 Verdad Gallardo
Old Mar 1, 2009 | 02:02 PM
  #9  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
everything is fixabe the question is how much =)
Reply
Old Mar 4, 2009 | 08:04 AM
  #10  
C43AMG's Avatar
MBWorld Fanatic!
Veteran: Army
20 Year Member
Liked
Loved
 
Joined: Feb 2005
Posts: 5,761
Likes: 4
From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
When is the last time the plugs,fuel filter and air filter were changed?Start with the basics for you start throwing money at theories.I would also look at changing the mass air sensor.

Last edited by C43AMG; Mar 4, 2009 at 12:42 PM. Reason: spelling
Reply
Old Mar 4, 2009 | 11:02 AM
  #11  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
All filers were changed last september when i had B-Service at the daler (or at least they claim so) plugs where not touched in last 2 years, and before that it did not own the car
Reply
Old Mar 4, 2009 | 12:43 PM
  #12  
C43AMG's Avatar
MBWorld Fanatic!
Veteran: Army
20 Year Member
Liked
Loved
 
Joined: Feb 2005
Posts: 5,761
Likes: 4
From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Originally Posted by alexus
All filers were changed last september when i had B-Service at the daler (or at least they claim so) plugs where not touched in last 2 years, and before that it did not own the car
Then , beased upon your mileage, the plugs are due.I would change them and then look at the mass air sensor.
Reply
Old Mar 4, 2009 | 02:08 PM
  #13  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
which plugs are better for reasonable price?

I can see bosch platinum plugs goes from $2 to $50 per each peace, but what is the difference? paying 50 x 6 = 300 for plugs alone is a bit too much for me on another hand 2x6=12 makes me cautious for low price

mass air sensor - where it is located?
Reply
Old Mar 26, 2009 | 11:32 AM
  #14  
AcousticplayerJ's Avatar
Member
 
Joined: Mar 2009
Posts: 96
Likes: 0
2000 c230 Kompressor
Check for leaks. I had an issue like that last summer. My car would barely be able to push 30 MPH without using all the gas. It turns out that some oil was leaking into one of the air-intake filters and essentially starving the engine of air. The dealer figured it out and fixed it. Afterwards, the car ran like new. Keep in mind that cars can slow down as they age. Though, what you're describing is very unusual.
Reply
Old Mar 26, 2009 | 01:12 PM
  #15  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
well i went to a performance shop
they changed fuel pamp and spark plugs + filteres....
now it runs steady, but I think at the same time it runs steady as it has less power now hmm but is hard to say now i need more objective way of mesuring power...

I guess i will go to airstrip and do 0-60 test... i hope police wont see me there...
Reply
Old Mar 26, 2009 | 03:20 PM
  #16  
AcousticplayerJ's Avatar
Member
 
Joined: Mar 2009
Posts: 96
Likes: 0
2000 c230 Kompressor
I recommend taking your car for like a 30 mile trip or so on the highway. My car always runs better after some good highway driving. If you can, take it up to about 60, then gun it up to 80 or so. Push the car a little bit (but not before it warms up!). That should help prime everything a little better. I would say that if you don't notice anything after like 150 miles, have them check it out again. By the way, does your car have a supercharger? If so, those add a bit of power, but take a second or so to kick in. So initial acceleration won't be so great, but then the car will fly.
P.S. just watch out for cops if you're going to go past the speed limit. They hide everywhere!
Reply
Old Mar 26, 2009 | 03:27 PM
  #17  
alexus's Avatar
Thread Starter
Junior Member
15 Year Member
 
Joined: Mar 2008
Posts: 46
Likes: 3
ML350 '06, SLK55 '05, C280 '97
well afetr reak good worm up car goes pefect... drove it at 80mph...
but nost of the time i goe 20mpg in the city like and thats like terribel but at the same time i dont gas to much in the city line... no point geting fast and then wasting the brakes in 1 min on the nex light

PS: unfortunatly dont have supercharger... i'm not sure if i can get one in good condition for W202
Reply
Old Mar 26, 2009 | 07:31 PM
  #18  
AcousticplayerJ's Avatar
Member
 
Joined: Mar 2009
Posts: 96
Likes: 0
2000 c230 Kompressor
Glad to hear it's working well. My car takes a few min to warm up before it's good too. But after the initial warm up, all is great!
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 05:17 AM.

story-0
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9
10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE