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I don't know what a compression test is or how to do it honestly. I wanted to see if it could be the spark plugs so that I can go on and order my parts.
Bosch
Spark Plug; Copper; Standard Electrode; OE Plug
Will this tool do for the spark plug extraction? I already have the cover and air hose off. I just need the tools for the spark plug only. It turns out that my dad had a few old drill bits that I used for that purpose.
If my calculations are correct, the car has a 10.1 compression ratio, which means the compression when checked with a compression gauge should be 165 when new from the factory. Allowing for wear, 155 is acceptable.
All cylinders should be very close to each other.
If one was 135 or 125, or lower for example, then you need to be a bit concerned
No torque wrench necessary.
You will need a compression test gage. The check involves pulling each plug, in turn, and inserting the gage in each plug port. Crank the engine and read the pressure for each cylinder. Youtube may have some good vid info.
If you are unsure of the age of the current spark plugs, it would be sensible to replace them at the same time.
Here is one that would be suitable:
The other option is, if you have a repair shop local, they could do this for you. Maybe an hour labor. If you buy a compression tester you may never use it again.
You are making this more complicated that it needs to be.
Buy a plug socket to fit the plug, and get it with a rubber ring inside to grip the plug. The parts stores will have it.
A compression check is done on each cylinder to tell the mechanic if there is a problem with things like the rings and the valves.
With the questions your asking, are you actually reading what I am sending you? I am trying to help you out, and spending a lot of time trying to be as precise as possible. If the information has no value to you, then I won't bother replying, as it is time consuming.
If you have unscrewed the plugs but are unable to extract them from the holes, use a piece of rubber tubing with an inside diameter of 1/4" to 3/8". Push that down over the spark plug to grip it and pull it out.
Or, as ptcruiser suggested, a spark plug socket.
I'm sorry for seeming repetitive, but this is my first time working on a vehicle. I want to make sure that I don't mess anything up or cause anymore damage. That is why I keep asking so many questions...
No apology necessary. You want to learn which is good. Not likely that you will break something but you could make something more complicated.
What are you trying to do at the moment, to resolve the misfire?
Yes, I am trying to resolve the misfire. I'm just still confused as to what I use to remove the spark plug. Is it a hex socket that goes inside of a wrench? Does that socket unscrew the plug? Thanks. I'm just confused.
Ok, basic start at what I think you are trying to do. Let me know if this is helpful.
These photos show a 3/8 drive rachet wrench with 6" extension and spark plug socket. You will need these to unscrew the spark plugs.
Okay, I got that so now what do I use for the torque part, like as far as putting them to 15-22lb ft and how can I tell that they're at the correct torque?
Ok, cool. Now we are on the same page.
The torque is not critical for spark plugs vs suspension or steering bolts. To be honest, most of us do not use a torque wrench on spark plugs because we can "feel" how tight they are.
It is more important that spark plugs be tight enough so they do not leak cylinder pressures.
In order to properly torque them to the 15-22 Ft Lb, you would need a 3/8 drive torque wrench. You can rent these at some auto part stores or hardware stores.
I suggest you tighten them with the same force they needed to be removed. There is a metal seal gasket on the new spark plug that "crushes" when sufficiently tightened. You will feel when this gasket is crushing and when it stops.
You stop tightening at this point.
Incorrect. Typical ratchet wrenches are reversible. Depending on the manufacturer, they have a lever or button which switches them from right to left turn.
Does your Mercedes have the tool kit it originally came with?
You should visit an auto parts or hardware store and hold these tools in your hand.
After you do that, report back to me and we will discuss what you have learned.
Okay, so I have my list so far. From Autozone, I need 6 Bosch Copper Plugs (F8DC4), a spark plug extractor (what size), the rubber tip to go inside of the plug, a Hex Socket, Chevron Injector Cleaner, and a Horn Fuse. Do I seem to be missing anything at all?
Well, as Zayed mentioned, a full diagnosis is always the best way to pinpoint a problem. An OBD 2 can work to get the codes, but the Mercedes Star system is the best. Is the check engine light on?
To get back to your question, look at the Youtube video about cleaning the throttle body,
You will see how it's removed, and there are 3 things to remove, before removing the throttle body from the manifold.
1. the air intake tube that runs from the air cleaner box to the throttle body.
2. the electrical connector on the left side (be gentle so you don't break the clips).
3. The small rubber tube on the right side of the throttle body.
If you don't have the tools, maybe take it to a shop that does, but maybe some friends will have what you need. A lot cheaper.
Note to Zayed: Got the mirror in, and it works just fine......
Agree with your input bro., and glad to hear mirror works, great joooooooob..
03-25-2015, 03:45 PM
