Strainger

I have another thread or two about my ongoing saga in fixing my 2002 w203 c200k M111.955 Evo. During my efforts it developed a misfire on cyl2 - ignition coil and spark plug dismissed as possible error.
Question: shouldn't my ELM327 with Torque lite report this new error? It is saying absolutely nothing about fuel injector being the possible culprit, etc?
Just wondering: do I have a ECU fault?

Russell Ormerod

You use the cheapest tools and blame the most expensive parts. Have you checked everything mechanical related to cyl2 ?
use Das forget about these cheap scan tools

Strainger

Hi Russell. thanks for your response.

Yes, my tools are cheap (ELM327, right), but it is what I can afford. What I have checked on cyl2 thus far is ignition coil, spark plug, harness (still not there with the harness). I hope that it will be possible to swap fuel injectors between cylinders as well to eliminate possible suspects - or to determine one.

My question on the OBDII readings, whether it would show a misbehaving fuel injector, for example, comes from a place of ignorance. Yet, the fact that I seemingly caused the cyl2 problem during my efforts to solve other problems (first start after putting everything together again), but I DID NOT get an additional reading on the OBDII scanner, regarding the misfire, seemed a bit strange to me.

At the same time, I saw the videos of GrooveOn, ,who fixed his malfunctioning sc pulley, and the air bypass flap for the sc not working at all, in one go, by replacing a mosfet on the ECU. Seems to me it works like: ECU sends signal and must receive signal back to interpret a reading. If it doesnt, something on the ECU, especially one 19 years old, as in my case, MAY just have some malfunctioning transistor or switch or something - meaning the ECU never sends a signal in the first place, right? (Taking as a given that the problem will most assuredly rather be located in part itself, wiring, fusing... etc)

Mate, its been a month or so since I picked up a spanner with serious intend for the first time, and even though I fixed 0 out of the four errors on the OBDII in round nr 1, for round nr 2 I know at least what a switch-over valve and what a shut-down valve is.... or an O2 sensor with circuit malfunction... camshaft censor... etc, etc, and though we wannabes may be extremely frustrating to you old vets, I am just SO chuffed by what I have learned in the last month - with basically zero dollars to help out.

Strainger

I apologize: every time I insert a link to a video, it shows up with this huge frame. How do I refer to a link without doing that, just put the address in normal text?

Strainger

Still seems to me a fair question: will cheap OBDII show up errors like misfiring fuel injectors, etc?

Russell Ormerod

No. Ecu can only check the electrical circuit to the injector. If the injector doesn't open mechanically or is blocked the ecu will not detect it.

112233

Two remarks (I'm searching a rough running on the same engine myself right now): The video is not the 111.955, its the earlier model with the M62.
Misfire is detected by measuring the acceleration of the crankshaft from the CPS between each ignition. Its throwing a code when something is really broken not only worn.

Strainger

Ok, thanks, understood. Perhaps something like a P0302 - "Cylinder 2 Misfire Detected"? I accept it wont specify 'fuel injector' or what have you.

Please let me explain how I get to this, if you are interested to read. My engine symptoms started out with CEL, lack of power (sc not engaging, flap staying open), car will not start on first crank, and the following OBDII:
p0102 Mass or Volume Air Flow Circuit Low Input
p0010 Mass or Volume Air Flow Circuit Malfunction, Hot-film mass-air sensor ME-SFI – fault code description.
p0135 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
p0414 Secondary Air Injection System Switching Valve A Circuit Shorted

Cleaning the MAF would allow power to come back, but eventually that didn't make a difference either. Everytime I checked the MAF, it had some oil in it.

I tried to fix the problems - my first ever mechanical endeavor - and I will describe everything if required, but I only ended up with a misfire. All the OBD readings and other symptoms remained, but something I did obviously caused, or accelerated, some problem.

Then a new reading showed up: p0340 Camshaft Position Sensor Circuit Malfunction.

I scoured the internet for info, and found the trend of leaky cam sensor -> oil in harness -> oil in O2 sensors and/or ECU (or at least ECU connectors) - and in general, this causes some cylinder to misfire. https://www.benzworld.org/threads/oi...-leak.1557833/, https://www.benzworld.org/threads/oi...-leak.1557833/

The magnet cam sensor on the front of my engine is definitely spilling oil like a river, and the first harness connector is full of oil. I did not find any oil in the post-cat connector, haven't checked the pre-cat yet, because I could not find it . Cleaned everything with electronic cleaner on the way.
Could not make out much on the ECU connectors, eyesight like a rhino, and just because I am a stupid a**, I pulled out the ECU while I was there. Sprayed every connector with cleaner, but I have no clue how to open the ECU.

I realize you probably think I am a fool, but I would like to clean and check the ECU - there are enough info on the net to point in this direction.

Strainger

One more question: Torque Lite interprets p0010 as "Mass or Volume Air Flow Circuit Malfunction, Hot-film mass-air sensor ME-SFI – fault code description."
The most common interpretation I find, though is "The technical definition of P0010 code is ‘A’ Camshaft Position Actuator Circuit Bank 1."

Sort of big difference there, so does DAS give the second definition, Russell?

Strainger

Ag, wait, it seems like Torque Lite is confusing p0100 with p0010. P0100 is Mass or Volume Air Flow Circuit Malfunction.

Which proves your point about DAS, Russell... however, I cannot afford a new cam sensor, nor even a new MAF, so... Torque Lite will have to do for now