dano582

so I just bought a 2002 clk430 the seller told me it needed a new maf so I took a scanner and it had a mad code . when I drive the car all gears change nice and smooth but I did notice it didn't downshift as quick as it should. so I ordered a used Bosch maf installed it cleared the code and no more error code now the car takes of with plenty of power and seems to downshift correct but when I'm really heavy on the accelerator the car starts to burp like power cuts of and on for a few seconds and causes a very violent jerk I don't have a mad code anymore if I put my old maf back on it goes away but it happens with the new one. any ideas on what can be the problem

thanks for any help

insame1

whats a mad code?

A1EK

Just sounds like to me that the MAF you bought is faulty. I would return it.
Try disconnecting the MAF cable and running the car, it will drive a little less well, but if the gear changes are okay then it will tell you its the MAF.

PS is the oil on the MAF?

dano582

sorry it's suppose to say maf for mass air flow but the auto spell check changed it...

so you think the used maf maf is bad ? wouldn't it trigger the check engine light?

dano582

So I took the maf that I bought and put it my e320 and the car ran fine.. I also took the maf from my e320 and put it in the clk and the car runs the same. I'm about to put the original maf back on the car , I rather deal with the car stumbling a bit on take of but at least once it going it **** nice and smooth at the moment if i give the car more then quarter throttle it will sputter like carzy

miatawnt2b

How old are the plugs? Id start there.

dano582

I have no idea I just bought the car.. the did remove my she valve today to clean the tube because I'm getting a p0400 code but once I got it out it was actually pretty clean..

dano582

I'm starting to think i may have a bad o2 sensor shouldn't they all look like the first pic?