How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Greg Your Own Question
Greg, Technician
Category: Car
Satisfied Customers: 7394
Experience:  Automotive diagnostic tech
Type Your Car Question Here...
Greg is online now

The engine management light is on and the car lacks power

Customer Question

The engine management light is on and the car lacks power for example on a motorway speed suddenly reduces from 70 miles an hours to 40mps.Stop the car ans restart and it is fine. Fuel system has been cleaned out but car is still doing it. It originally only occurred on motorways but is now doing it on a roads where I am travelling at slower speeds. Could this be a result of the glow plugs need replacing and/ or anything else. It is a 2008 Disel mercedes car. past MOT May and just had a main service.
Submitted: 9 months ago.
Category: Car
Customer: replied 9 months ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call.
Customer: replied 9 months ago.
Let me know if you need more information, or send me the service offer(s) so we can proceed.
Expert:  Greg replied 9 months ago.

Hi, I'm Greg (Indy-Tech).
Welcome to JustAnswer. I'm reviewing your question now, and will post back with your reply ASAP.
Rgds Greg.

Expert:  Greg replied 9 months ago.

Any warning lights come on wghen the engine is running .

Like the check engine light or is the glow plug light flashing .


Customer: replied 9 months ago.
The engine light is on, and the light like a metal coil comes on some times but surprisingly today is the first my engine management light has not come on. When it lacks power the ESP light triangle light comes on everytime. It first started doing it on the motorway and has started to do it on the minor roads
Expert:  Greg replied 9 months ago.

Okay this is the check engine and glow plug warning lights .

You need to get hooked up to a diagnostic scan tool and check for malfunction codes .

You could have a possible issue with the air flow meter or any of many engine sensors .

also possible and most likely a problem with the throttle control system , but to confirm you need to have a scan tool hooked up and check for malfunction codes ..

For further assistance with this issue please get back to me with the reply box below .
This is not a one answer and done i/we will stay with you until the problem is sorted out .
Before rating poor or bad please get back to me as i'm here to help you, if i can't i will opt out so another expert can.
We want you to be happy with an answer and help you with your problem . Want you to be a happy motorist .
After rating there is no further cost for any other question relating to this problem
Kind regards Greg..