Hey all!
Not new to the forum however I am a new member. Lots of knowledge on this site so I thought it was time to show off my build,
my headaches, and my victories with it so far..
hoping this will help others where I’ve struggled and maybe even help me with the build.

Car: 2005 C230k 6 speed.

long story short, purchased the car almost 2 years ago, car ran ok when I bought it.
mostly stock with the exception of a magnaflow cat back, and a POS junkyard welded downpipe that one of the previous owners installed, bc coilovers, wheels and wheel spacers.

After a while I noticed all exterior lights went out on the car. Eventually noticed that when the car would reach normal operating temp it would misfire. if left at idol at a red light for too long it would start to have a very rough misfire and persist until I restarted the car, and then come back. After very lengthy investigations by myself, multiple mechanics and specialists, 2 mb dealerships, a friend of mine was able to identify it was the sam modules (both front & rear) that where bad causing the exterior lights to go out with no fix for the misfire. Replacing both of the Sam modules fixed the electrical issue(temporarily). A few months passed by and the car sat in my driveway.. finally got time to work on the car and the lights did not come on again.

after going over the car front to back I found that the vent drains between the windshield and the hood where FULL OF SCREWS!! Leaves twigs And other debris, which caused water to pool on the dash and enter through the passenger side pillar and onto passenger side floor board affecting ALL of the grounds in that area- directly affecting my Sam modules.

with that problem solved after getting it all dried out, and fixing the electrical issues/connections, replacing the Sam modules AGAIN, and the ECU Something was still cutting fuel to that #4 cylinder or telling the ecm to cut fuel.…it still had a misfire.
using a borescope we examined the inside of the head and saw what we believed was carbon buildup or possibly a hairline crack on the head, causing the ecm to read improper volume, which in turn was cutting fuel. At the time I was also getting a bad o2 sensor code which I replaced and didn’t fix my issue.

Instead of dealing with the issue as is.. and spending who knows how much on parts, plus my own time tearing it down, I decided to purchase a used motor(under warranty) for less than $800.
Compression test was good so I decided to move forward with the swap.
throughout the process I’ve replaced
alternator, battery, ps pump, ac compressor, voltage regulator.
clutch was replaced with a new/oe and flywheel (for the sake of not spending an arm and a leg) was resurfaced instead of replaced.
i have removed the baffle in the main supercharger plenum and very lightly polished s/c inlet.
i also purchased a new aftermarket dp/ headers from Beckett exhaust which was listed as a direct fit but I believe either my flow master cat back has different connection points, or it’s the incorrect DP for the car because the headers fit, but the downpipe does not line up with a cat back.


Long Term Goal

Up until this point I have been planning to fully rebuild my old existing motor with the intent of doing a full race p&p, supercharger pulley/ lightweight pulleys & tune- assuming I can get the Becker exhaust to work with the car. I know the c230 was never meant to be fast, but around 200hp at the wheels (if possible) with the right suspension setup i think it would be a great competitor on the track against friend’s cars (Miata, e46/36 and other cars sub 250hp)

Short Term Goal

for now I’m just trying to get it through state inspection.
After having the swap completed, got all new fluids installed and ran the car a couple of miles. at this point the car is running & driving. Gears feel great, clutch feels great, the power in the car feels great as well. Had to reinstall the old headers/dp because the new 1 would not line up. But still had an o2 sensor code. Replace BOTH o2 sensors because why not? I’m already there and have the exhaust off.. might as well, and guess what? Still has an o2 sensor code. At this point I’m thinking it has something to do with that junkyard welded exhaust. Aside from throwing another o2 sensor at it or spending the cash for an OE exhaust manifold w/dp I’m not sure what else to do.
o2 sensor code is the only code I currently have in the car. Motor sounds good. Clutch it good gears are good (did change transmission gear oil as well).

If you stayed this long I appreciate you taking the time to ready my story with this car up to this point.
any criticism, assistance, knowledge, or motivation anyone could offer would be greatly appreciated.

PSA to all the tuners out there…
a friend of mine who is a MB specialist informed me that there is a possibility that the o2 sensor code could be programmed or tuned out… if this is true or even a possibility please let me know. To me it makes sense because any type of tuning for power would affect the readings at those o2 sensors anyway or so I would think correct me if I’m wrong? Or if anyone could assist with this message me please!

 

welcome to mbworld...

 

Hi @Anthony05c230 and welcome to the club! Thanks for the intro and the pics. Looks like you’re done heaps of work on your C230, and looks in great condition. All the best with it 👍

 

thanks man I appreciate that. It’s still a work in progress although I’m almost done with this engine. Still considering building my spare motor or swapping a clk front end to fit an m114… and I’ve only seen 1 person do it in California so I may be the first on the east coast if I decide to go that route. Any input is appreciated

 

Welcome!