Claudiop

I have been a non-active forum user for several months on the forum, since I bought a 2002 Mercedes S430. I never really thought I needed help, until something started to go wrong.


I currently have misfires, which started with a "Missfire ON CYLINDER 3", which I would like to express in another post. Based on what I found out here and from other sources, I have purchased the ignition coils (all of them) and the coil cables. The first thing I did was replace the coils (purchased on Amazon), and the problem continued.

Today I intended to change the coil cables (bought on Amazon as well), to see how the car behaved. I tested them for OHMS, with my multimeter. The problem is, the coil leads read 1 OHM, and according to all sources, the leads should be 2 OHM. It may seem like a pointless question (I know I shouldn't), but...


Will the 1 OHM cables be enough to replace the current 2 OHM cables?

Thank you very much for your help! (forgive my terrible English).

kraut56

START BY LEARNING FROM MY POSTS HERE AND "THERE"
Misfiring information on MB engines can be much more difficult to interpret, and usually only with SDS,
Very often these misfires are caused by catalytic converter problems, where the ECU shuts down the upstream cylinder to protect the catalytic converter.
Just throwing parts at it will not fix the problem.
Get a proper SDS read out,
and report the results.

Claudiop

The story begins like this. I bought this car about 6 months ago. Intermittently about 4 months ago the check engine light came on and went off within a week. I did a basic OBD2 scan and it returned the code "P0130, heated oxygen sensor (HO2S) 1, bank 1 - circuit malfunction. The result of this is that the vehicle felt a little heavier when accelerating. A few weeks ago

, I had the check engine light again, I did a basic OBD2 scanner (ELM327) and now in addition to the P0130 code it also shows the P0303 code, a misfire was detected on cylinder 3. Thinking it was a bad spark plug, I took the vehicle. to a nearby mechanic.

I went to the mechanic and he suggested changing the spark plugs. NGK BKR6EGP, 7092 spark plugs were installed. The procedure took a while, so I went to do other things while the spark plugs were changed. Before leaving I was a witness. The mechanic applies some MAF cleaner, directly without removing the sensor. Once the spark plugs have been changed, I go back to the shop for my MB and the mechanic tells me that the vehicle still feels "heavy." After that, an FCAN scan. is done, which returns the following codes:

P200F - [4] G3/4 (right o2 sensor, before TWC [KAT]; Open circuit (P0134).

P2050 - Ignition error. TWC Damage (P0300)

P2051 - Cylinder 1 Misfire, TWC Damage (P0301) P2053

P2056 – Cylinder 5 Misfire, TWC Damage (P0305)

P2044 - Cylinder 1 Misfire (P0305)

P2046 - Cylinder 3 Misfire (P0303)


The mechanic cleared the codes and told me to come back when the engine control came back on. 2 days later the engine felt very unstable and the revs were fluctuating between 700 and 800 at idle (you could feel the engine moving). On the way I didn't feel anything, but returning to my house, at approximately 90 km/h the check light started flashing. I didn't stop and it continued normally. 10 minutes passed, I reached the gate of my house and the vehicle turned off completely. I have started to work. I bought new coils and new cables. Changed 3 coils that appear in the reading above. The effect of this is that when starting the engine from cold it starts with great difficulty,
It shakes a lot, it lasts approximately 10 minutes with the revolutions between 400 and 1300. In periods of time within these 10 minutes it normalizes at times (40 seconds). 10 minutes pass and it turns off completely and then it won't start.

I know I should make another scanner at home (as professional as possible), but my question was, can I (FOR TESTING ONLY) use the 1 OHM coil leads (I intend to return them).

Thank you very much for your kind help!

PS: I have ordered the o2 sensor and it should arrive in a few days.

ygmn

better way to test for misfire is to swap parts from a good cylinder to the one missing.

so in your case - swap say #1 & #3 wire.
Test - did problem move or stay?
IF moved you found issue.
If not then swap them back and then swap another part from a different working cylinder say plugs from #3 & #4. whatever is easiest.
Did you find issue by all that swapping?
Check compression on that cylinder.
Check for intake leaks near this cylinder.

Check online as there are many good write ups on how to trouble shoot misfires

No sense putting in new parts until you know the originals are bad.
Also Amazon parts can be crap and broke out of the box; heck even new parts from other venders.

Also wait ono@ as they would effect all th cylinders or if 2 upstream sensors would effect the all the cylinders on that side.

kraut56

See again my post #2, and do searching on this and the other forum, where I have posted for this problem.

P200F - [4] G3/4 (right o2 sensor, before TWC [KAT]; Open circuit (P0134).

P2050 - Ignition error. TWC Damage (P0300)

P2051 - Cylinder 1 Misfire, P200F - [4] G3/4 (right o2 sensor, before TWC [KAT]; Open circuit (P0134).

P2050 - Ignition error. TWC Damage (P0300)

P2051 - Cylinder 1 Misfire, TWC Damage (P0301) P2053

P2056 – Cylinder 5 Misfire, TWC Damage (P0305)

P2044 - Cylinder 1 Misfire (P0305)

P2046 - Cylinder 3 Misfire (P0303) (P0301) P2053

P2056 – Cylinder 5 Misfire, TWC Damage (P0305)

P2044 - Cylinder 1 Misfire (P0305)

P2046 - Cylinder 3 Misfire (P0303)

When you see . TWC Damage it means the ECU is shutting down that cylinder to protect the corresponding cat, because it doesn't like the lambda o2 sensor reading.
Usually the cat is partially blocked or doesn't "fire up" properly.

Your scanner reader is iffy, you should use MB SDS.
just changing plugs, wires, O2 sensors will get expensive and is not the proper way.
search and read!

96_C280

If I had to go off pure guessing at this point, I would try swapping the MAF and see if it makes a difference.