Hello I have a 1997 e420 with 79K miles on it. It has a knocking noise that everyones says is a lifter. I call it a knock instead of a tap because it as loud and at a lower frequency than most taps I have heard. IJt seems to come from the drivers side. I pulled the valve covers to check the oil tubes and there are none broken. I just purchased the car and when I pulled the covers the oil was terrible. I cleaned everything and even removed the tubes and cleaned them out although none seemed to be clogged. Still has the knock or (Loud Tap) What should I do next. None of the lifters look bad or push down overly easy. Is there another way to check them without pulling the cams. Is there a secret to pulling the cams without messing up the timing? I am also reading some codes from the same head that has the tap. I am reading a misfire on all 4 cylinders or that head. Is this common with a faulty lifter? Any info on changing the lifters without screwing up the timing would also be great. Is it recommended to change all lifters at the same time? In readng some other post someone has come to the conclusion that a bad catalytic converter can cause this what do you think. Here is a clip from someone elses car but it sounds just like mine. YouTube - 97 mercedes s420 knock Thanks, Ben
Welcome to the forum, Ben1. Please take a moment to complete your user profile, available via the "User CP" link.
I haven't even been inside my own motor, so I don't have a lot of help for you except the things that apply to all engines. By your questions, I would guess that you already know the basics.
Hopefully someone who's been inside your motor will respond before very long.
I pulled the covers and checked and evern removed all or the oil tubes and they were all OK. More information. The noise seems to come from cylinder 7 (screwdriver test) I did a compression test cold and found 207, 200, 209, 207, 210, 190, 140, 110. The 140 and 110 being #7 and 8. What can cause this? Could a lifter cause this? Does not seem like a cat can cause this on only a few cylinders? Is this engine history. What should I check next?
Thanks
Ben
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Ben
1997 Mercedes E420
79000.00 miles
a leak down on the engine, and since the two cylinders are right next to each other and 30-50% percent off the norm,I would suspect a blown head gasket..Did you keep a sample of the oil in it when they sold it to you?
ohlord
The oil was very thin but was not grey in color or milky as if it had water in it. Just looked like it was abused and not changed in quite a while. Would a stuck lifter or jumped timing cause this. I am trying to put together what would cause the compression issue and the knock at the same time?
Thanks
Ben
Linear Mode
