Irratic power delivery - A Class

[alex b]

I have been driving the wife's A class a few times this week, and the pick up of power seems to be very stalled and sluggish and then all of a sudden the power picks up and surges forward.

Has anyone else experienced this?

I'm not quite sure what it could be.

Fuel injectors blocked?

Can anyone help please?

[tonylal]

What engine, age and mileage is it?

[motorwise]

needs to go on a scanner for diagnosis - your local independant garage should be able to do this for you

[alex b]

tonylal said:

What engine, age and mileage is it?

Its a 1.4 2000 plate, 54k miles.

Problem is, it doesn't get used everyday.

[sneijder]

If it's juddering and jumping up to full power, it's the coil pack over the four spark plugs that's at fault - change the plugs while your at it and you'll be looking at around £100 for the parts.

If the lack of power is more lumpy than juddering it's the Air Mass Sensor that's failed. The bad news is that the sensor is built into the Engine Control Unit, meaning it's around £700 for the part, and a good weeks wait to get it delivered.

[alex b]

sneijder said:

If it's juddering and jumping up to full power, it's the coil pack over the four spark plugs that's at fault - change the plugs while your at it and you'll be looking at around £100 for the parts.

If the lack of power is more lumpy than juddering it's the Air Mass Sensor that's failed. The bad news is that the sensor is built into the Engine Control Unit, meaning it's around £700 for the part, and a good weeks wait to get it delivered.

So if its the air mass sensor that should be covered under our warranty we got with the car from MB.

I think the best thing is to take it in and see what they say.

Cheers fellas

[Parrot of Doom]

Hi there

Just a chance, try cleaning the MAF. I did a guide, should be a very similar process on yours:

http://mbclub.co.uk/forums/showthread

[alex b]

sneijder said:

If it's juddering and jumping up to full power, it's the coil pack over the four spark plugs that's at fault - change the plugs while your at it and you'll be looking at around £100 for the parts.

If the lack of power is more lumpy than juddering it's the Air Mass Sensor that's failed. The bad news is that the sensor is built into the Engine Control Unit, meaning it's around £700 for the part, and a good weeks wait to get it delivered.

Just had a call from MB, and Sneijder you were spot on.

It is indeed the Air Mass Sensor that is knackered.

Going to collect the car and wait for MB to speak to the warranty centre to approve the work.

£631 and a weeks wait on order from the motherland.

Fingers crossed the warranty peeps approve it.

[Goldenglow]

We have got a similar problem with our A class. Just asking how long was your warranty and how did you do for Mercedes to admit their failure?

[alex b]

Goldenglow said:

We have got a similar problem with our A class. Just asking how long was your warranty and how did you do for Mercedes to admit their failure?

We bought the car last year and I negotiated a 12 month warranty into the sale price.

I had no problem with the dealer replacing it under warranty, however the procedure was that the deler had to get authorisation from the warranty people.