My 1996 Mercedes C280 will occassionally lose acceleration, pick back up, and lose it again

10

Asked by David Aug 18, 2012 at 01:31 PM about the 1996 Mercedes-Benz C-Class C 280

Question type: Maintenance & Repair

Unfortunately, my mechanic cannot reproduce the problem.   I will be driving at normal speed.   I stop for a stop sign or light, and when I accelerate it tops out at maybe 20 mph and then slows down to 5-10 mph, speeds ups to 20 mph, etc.  The accelerator is held at a constant depression.  If I put the car in Neutral, the engine cycles through the same loss and pickup of power.  If I stop the car, and let it sit for a few minutes, it typically does not reoccur on that trip.   It is not easily repeatable, but the 3-times it has happend to me seem to have the same pattern:   I drive the car for about 30', I park for about 15' (i.e., the engine is still warm), I start driving again and it occurs.  I have had several refills between incidents so I don't think it is bad fuel. My mechanic's only guess is the fuel pump, but they are hesitant to replace it without knowing for sure due to the expense.  I am trying to get the problem to occur again so that I can drive it (slowly!) to the mechanic to experience it first hand. Thanks for any ideas.

8 Answers

10

A bit more info. My mechanic actually identified several other possible culprits including the Mass Airflow sensor, but without knowing did not want to just start replacing parts willi-nillie. They had the car for this last week, tried to reproduce the problem, to no avail.

1 people found this helpful.
60,215

I would check the ECT (Engine coolant temperature) sensor. Also check of vacuum leaks. For some reason when my car had a vacuum leak it ran worse at times like you describe. When it was restarted at a temperature in between cold and operating temperature.

2 people found this helpful.
10

Thank you Andrew. I know my mechanic checked for vacuum leaks but he didn't mention the ECT as a possible culprit - I will mention this to him!

12,505

I would first get the codes read off the ecu, it should be throwing a code, and that would lead you in the right direction into solving the problem. It sound to me like you have a failing throttle actuator. These cars have a drive by wire set up. The accelerator pedal is not connected directly to the throttle body, but instead to a module that sends a signal to the computer which in turn controls the opening and closing of the throttle through an electric motor. It's all electrical and prone to failure.

7 people found this helpful.
60,215

I was unaware the car was throttle by wire. If so that is a definate possibility. Thanks Lorne

10

Hi Lorne, thank you. That is useful information that I was not aware of!

20

my 96 Mercedes i just bought is having this SAME problem, but this happens to me Once or Twice per week. i noticed either the ASR or ASD light comes on as soon as i stop at a light or stop sign, then i cant accelerate at all ,if so hardly. I Read that the ASR and ASD are Anti Skid protection by the cars CPU. I ALSO read that you can Remove or Disable it. and being i dont live in the heavy rain or snow it shouldnt matter... Does anyone know how i go about disabling the ASR/ASD?????

2 people found this helpful.

My 1996 c280 does the same and it will rev up while in park ...took to get code and mass air flow sensor showed up......I will pick it up in the AM....I'll post results

Your Answer:

C-Class

Looking for a Used C-Class in your area?

CarGurus has 1,429 nationwide C-Class listings starting at $4,499.

Postal Code:

CarGurus Experts

  • #1
    Lorne Grandison
    Reputation
    12,420
  • #2
    zabi
    Reputation
    5,600
  • #3
    PPC123
    Reputation
    5,150
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Mercedes-Benz E-Class
33 Great Deals out of 612 listings starting at $5,450
Used BMW 3 Series
66 Great Deals out of 1,237 listings starting at $3,995
Used Mercedes-Benz S-Class
19 Great Deals out of 199 listings starting at $7,500
Used BMW M3
9 Great Deals out of 82 listings starting at $15,850
Used BMW 5 Series
21 Great Deals out of 303 listings starting at $2,900
Used Chevrolet Corvette
29 Great Deals out of 593 listings starting at $10,989

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.