CL500 ??Power on high revs??

[greekCL]

Hello Guys,

I will try to describe it in the best ... way

The car (CL500 W215 '00 model) drives fine and really smooth. When you boot it down, and especially in excess of 60-70mph ... it will accelerate fast but it will have moments that it will give even more power for a second or two. So in a one off acceleration it will have 2-3 seconds of "boost"
So let me give you an example ... accelerating from 50mph to 100mph lets say....
50 to 70 smooth accelaration and all dials go fast up ...
70 to 80 it will go even faster (the second which is more power than normal)
80 to 95 smooth acceleration
and from 95 to 100 some more power kicking in out of nowhere.
When it does that or after long trips the check engine light will come on the dashboard, but this does not affect the driving of the car...
the light will go off after 1hr some times or after 2 days other times. It never stays on forever , it goes off by it self.

I have plugged in the car to the PC and it read Fuel mixture correction, and I though it would be the IMAF sensor, a friend suggested to take it off and wash it carefully with fairy liquid. So I did and dried it very carefully , but it is not make any difference.

Now the question is ... how do I know what is 100% faulty? before I start replacing parts and cost me a bomb...

Cheers
V

 

[GazCaff]

I can't see fairy liquid helping you MAF sensor, especially as it could leave a residue on the element. You are better off using Isopropynol Alchohol to clean it as this will evaporate to nothing.

I should also mention that touching the MAF sensor element with anything is a bad idea as they are very fragile.

 

[greekCL]

The electrician friend mentioned that sometime it might have a thin film of engine oil and that this could be cause by time... this would cause the sensor to malfunction.
He mentioned that fairy liquid would be best... but again this is an individual opinion...
it does not seem that it did any more hard than it was lol lol.
But just for a second opinion will the MAF sensor (located just after the air filters) cause such malfunction?

 

[amwebby]

Are you sure this isn't just the difference between 1st and 2nd stage kickdown?

Normal kickdown drops down 1 gear, depressing the accelerator pedal quickly shifts down 2 gears for a burst of rapid acceleration before shifting up to the gear you would be in with 1st stage kickdown.

 

[greekCL]

Did not know that Roger, good thing to know though.
No this is actually halfway through the kick down and it will usually be on the high revs ie 5000 to 6000
so lets say the kick down starts at 50mph, and I let the accelerator go at 100mph
It will start doing it around 65 to 65mph all the way to 100mph on and off lets say it will give you some soft of extra bhp every 5mph on the speedo.
It does not feel it cuts down, it feels like you are getting a kick on the back of the sit
lol

 

[Dieselman]

If your car has variable valve timing and intake tracts then it could just be that you can feel the switchover points.

 

[amwebby]

Did not know that Roger, good thing to know though.
No this is actually halfway through the kick down and it will usually be on the high revs ie 5000 to 6000
so lets say the kick down starts at 50mph, and I let the accelerator go at 100mph
It will start doing it around 65 to 65mph all the way to 100mph on and off lets say it will give you some soft of extra bhp every 5mph on the speedo.
It does not feel it cuts down, it feels like you are getting a kick on the back of the sit
lol

Still sounds like the 2 stage kickdown to me. As Dieselman says, you can just feel the switch-over points.

 

[greekCL]

ok fair enough... loads I did not know about automatics,

but what about the error code then? it records
Fuel mixture correction and the orange check engine light

 

[SG CL500]

The two stage requires you to push the pedal down harder past the switch point though - something you tend to feel on your foot as well as your **** surely... And it is accompanied by a noticable jump in revs

If you're keeping your accelerator in the same position the second stage shouldn't kick in, should it?

Sorry to hear of your woes Mr Greek - not having a great time with it at the moment by the sound of it

 

[BlackC55]

Fuel mixture correction could very well be an air mass fault or a lambda issue. What are the "live" lamda values for all 4 probes?

Washing it in Fairy liquid has probably damaged it. Not a good idea.

 

[greekCL]

oh well the fact it makes the same problems with before maybe it was already damaged lol lol
I will quote a price for the parts
I did not check for live lamda sensors I assume I need to get the car somewhre with a fuel exaust thingie as well and to read the lamdas. right?

By the way the fact I do not have any more the rear cats in place would it make much difference?
I only have the front cats in place, the rear were surgically removed as they were making noises like tractor

 

[BlackC55]

The lambda should be cheked via the OBD port not the exhaust atm.

 

[greekCL]

oh ok ... it is easier then
I will do that as soon as I get the car back.

Well the car does not have major problems it still drives like a dream I must admit.
It is just minor things I want sorted

I suppose as I have it half repainted from MB again ... and summer is coming
and I have one more driving trip to Greece coming this July

 

[amwebby]

On rereading this I would check the Lambda sensor and the upstream O2 sensors.

 

[SG CL500]

Out of intererst - what mileage is your CL now? I am up to 108k and concerned that I have a heap of issues just round the corner...!

 

[greekCL]

If I remember correct it is 118.000
But I would not worry if I was you... I am just perfectionist. On day to day driving you do not even understand it lol except if the annoying yellow check engine light coming up from time to time.

 

[amwebby]

Out of intererst - what mileage is your CL now? I am up to 108k and concerned that I have a heap of issues just round the corner...!

I'm just on 97k

 

[owensmith]

I heard from a local mechanic the sensors normally need changing at 100K? thats how long they last same as the cats he was right out bout the cats thou they both went last year 1 side went at 99K the second at 101K I have not changed sensor yet but will check them when i get time also when you use your kick down where do your revs start when you feel the power on my car i notice i get a considerable amount of power at 4000 revs this the way the cams are designed (4.3 V8 m113)

 

[greekCL]

Well my problem is that the power fluctuates from 4.000rpm and over ...
Measuring the power with a scale of 1 to 10 where 1 is lower and 10 higher output I get the following :

4000 to 4500 = 8
4500 to 4800 = 10
4800 to 5200 = 8
5200 to limit or changing up a gear = 10

This is just a way to describe what happens. The car does not feel to loose power, it seems to find power out of the blue while I keep my foot steady dag on the floor.

Maybe I need to change all the sensors, it makes sense that they get worn out after certain mileage... one God knows how much this will cost

 

[owensmith]

It was not a mechanic i got the info from I read it somwhere but a warning light should come up on dash if a sensor was not working correctly also your car would be drinkin alot more fuel? I got this info for lambda sensor

Lambda Sensors, No. 1 worldwide