TWSOCKS

it started spitting and hesitating at stop lights when trying to step on the gas, sometimes stalling other times spitting and going on, after each cycle throwing CEL and code p0104, tried new MAF, not as bad but still the same, checked all hoses and filter and box. Meter says MAF is fine but throttle body readings are peculiar.......HELP can't get rid of p0104 just keeps coming back to haunt me with hesitations etc.

Maj. Dundee

Do you have a DVOM (Digital Volt/Ohm Meter)?

TWSOCKS

Yes

TWSOCKS

Have measured each one all check ok but Mercedes told the mechanic that they were ok on top end but not ok on bottom end

Maj. Dundee

You have measured each one, what?

TWSOCKS

Yes 2 prior mafs were both check with volt meter

Maj. Dundee

Did you do these tests?

TWSOCKS

no im sure he has not I'll forward them Thanks

TWSOCKS

no im sure he has not I'll forward them Thanks

TWSOCKS

maj Dundee. You don't happen to be in Maryland ?

Maj. Dundee

Bronx, NY

TWSOCKS

wish you were here , I'm going back to the garage today and see if he can run those tests !

Maj. Dundee

Please UPDATE YOUR PROFILE in USER CP to include the ML.

TWSOCKS

Now it won't throw codes at all. But it's all when you stop at a light or stop sign and pedal it ,, wants to still spit etc but now no codes But while I was under hood trying to give it gas I kept hearing a vacuum leak at very back of motor and after you get it to take gas it's fine just the low end gas pedal not 100% sure where hissing is but middle of back of motor But all other tests ok

Maj. Dundee

Here is a photo of the vacuum lines at the rear of the eng. To get a good look at things you will have to remove the large plastic cover on top of the eng. Just pull it upwards and store in the trunk.

Using a large mirror look at all the hoses connected, especially the T-conn. at the top of the photo and see if it has a crack in it.

Post back with results.

TWSOCKS

ml500 p0104. Now this morning I left battery unhooked for 1 hour. And drove it 5 minutes no Cel but p0104 is back after completely clearing codes

Maj. Dundee

Because you disconnected the battery does not eliminate the vacuum leak. A vacuum leak that will occur whenever it wants to.

TWSOCKS

Thanks for all your help Maj Dundee. We took off manifold fixed bottom vacuum line and cleaned everything and replaced every hose etc..... and sooo far it's Grrrrrreeeeaaatttt .

Maj. Dundee

Which hose was it? Was it one of the hoses in the photo I supplied?

Please indicate which one it was so future members will know.

TWSOCKS

i "Believe" the one in front of manilfold that actually goes inside of the manifold front bottom we used a metal barb and put liquid steel around it .. to seal it and resealed the manifold back together and new gaskets etc... but we also replaced every hose and gasket their was .

Maj. Dundee

I hope you learned from this experience. Because a code is thrown, P0104, does not necessarily mean that the part is faulty and must must be changed, MAF Sensor.

TWSOCKS

yes how true.... although we did change out 2 mag sensors in the 1st few days not 100% what was the problem since we fixed 4-5