190e holding back

[190ian]

A few months ago my 190 seamed to hold back when accelerating then the power would kick in,
last week i changed the air fillter and box for a k&n style fillter and it has got worse, if i gently accelerate to the floor its fine, if you just floor it it holds back till bout 4000revs then the power kicks in again, Any idears

 

[ADY1983]

When was the car last serviced? and K&N style filters don't like some cars...

 

[190ian]

I cant rember the last time it was serviced, but it was holding back before i changed it anyway, one thing with the change is it is quicker once it gets going, would this problem come up on a code reader.

 

[neilrr]

Fuel pump?

 

[Ian B Walker]

A few things come to mind. If it has a cat is it partially blocked or, if not a cat, has the exhaust system got any bad kinks / bends in it? Is the OVP relay in good condition? Have you used any injection cleaner (they may be gumming up)? I am not convinsed that K & N Filters do any good to an engine, although some members here have used them to good effect. Yes fuel filter or pump could be a cause too but unlikley IMHO. Have you, by any chance, been playing with the control cable from the accelerator to the gearbox?

 

[andy_k]

as you can't remember the last time it was serviced have you tried changing the spark plugs?

 

[Birdman]

K&N filters have been known to cause Mercedes engine MAF sensors to become contaminated by the filter's oil and need replacing.
If your model has a Mass Airflow Sensor and your filter is a bit too well-oiled it might cause an already failing MAF to fail completely.
You can clean the MAF and it may sort it.
Just another something to check out.

 

[grober]

190's dont have a MAF! They have the older Bosch K or KE JETRONIC mechanical injection sysytem which uses an airflow plate to measure air intake. these can get sticky and its well worth giving the throat a clean up with solvent. Dont damage the sensitive mechanical plate linkage at the same time.

 

[Birdman]

http://www.getusedparts.com/automobile_guide/mercedes_benz/mercedes_benz_mass_air_flow_sensor.html

 

[Dieselman]

It sounds like the mixture may be too lean which has now been exaccerbated by fitting a free-er flowing air filter. Also check all the vacuum lines to the manifold.

 

[Birdman]

Pull out the new K&N and replace the old filter system after blowing it through with an air hose.
Better or worse?
I'd fix the problem without using the new K&N to rule that out as a cause.

 

[190ian]

Thanks for all your idears guys i will start with the fillter and check every think else out you have surgested doing.
Il let you know how i get on.