Main question: Is this worth buying and fixing?

Sorry for the story, but here it goes:

So I went to check out a 2003 c230 supercharged 4cyl tonight under the impression that it had one misfire code (p0304). So I get there and car starts up and has an odd idle for a few seconds and then levels out. Normal idle, albeit, rough, but pretty steady. So I plug my scanner in and there's some pending codes. The car has no power and can barely go over 30mph before it no longer has enough power to keep pushing. Guy wanted $1400 before I went to check it out. After test driving, while I tried to accelerate, there was a rattling noise that was audible for a quick second at which point I let off the gas and it stopped immediately. Supercharger seems a little noisy at idle, not a good noisy. But it's not super loud. Under normal acceleration, shifting around 2-3k rpm, everything sounds normal. Anywho, here are the codes that I got.

p0101 "Mass or Volume Air Flow A Circuit Range/Performance"
p0108 "Manifold Absolute Pressure/Barometric Pressure Circuit High"
p0638 "Throttle Actuator Control Range/Performance Bank 1"
p0301 "Cylinder 1 Misfire Detected"
p0302 "2"
p0303 "3"
p0304 "4"

Could a bad MAF be causing all these issues?? When I clear the code, the idle smooths out for a little bit before returning to rough after the check engine light comes back on, usually after revving it a little bit. I cleared it a few times and will also post the sequence in which the codes showed up after a fresh start. Also, the owner said he changed out the Throttle Actuator to see if that would help anything, but now that is throwing a code as well and kills the accelerator in the middle of driving it or when you try to take off from a stop.

First scan at idle before first clear:
p0301
p0302
p0304

Second scan at idle after first clear:
p0101
p0304
p0301

Third scan after clearing and driving about 1000 feet:
p0101
p0638
p0108

Any help would be greatly appreciated.

I went to look at this car to make a purchase but just worried about what the issue(s) may be. The guy only wants $1400 because he said he wasn't going to put any more work into it. Mileage is 171,xxx all stock minus some hard piping.

 

Try replacing spark plugs, cleaning MAF, cleaning throttle body, looking for obvious vacuum leaks, and disconnect battery for 10 minutes..

 

Try replacing spark plugs, cleaning MAF, cleaning throttle body, looking for obvious vacuum leaks, and disconnect battery for 10 minutes..

 

Well I would have to buy it first to do that. Do you think it's worth buying? Anyone?

 

Don't buy it. Sounds like timing chain jumped teeth.
Expensive repair, sprockets, valves...who knows?

 

Yeah I thought about that, but that doesn't explain why when I clear the codes, the idle is smooth and responsive. I would think it would remain rough if it was timing since it's all mechanical and clearing codes would only affect electrical components.

 

Ok, so here's what happened, in a nut shell. I bought the car for $1000. I towed it home and dove right in. First things first, finding out why I had random misfire codes. Pulled the coils with the idea of swapping the coils around and seeing if the codes followed. After pulling the coils, I noticed a lot of debris down in the spark plug hole. Cleaned it all out and still moved the coils around since they were already off. Misfire codes were gone. Still a rough idle and limp mode (can't rev above 4k rpms). Pulled codes again and go front o2 sensor and a MAF code (can't remember the code). I had the car running and proceeded to pull the MAF connector off just to see what it did. It did nothing. Car runs the same with or without the MAF connected. Isn't the MAF what controls the air coming in meaning if you disconnect it, the car should die? Anywho, I checked the connector for power and I'm getting 11.5 which is within range of what it should be. So I started to pull the intake stuff off to get to the MAF to inspect and clean it. After pulling it and inspected, I came to the conclusion that it was fine. Just when I was gonna put it back together, I figured it wouldn't hurt to clean it. While I was spraying the maf cleaner, a little piece of the metal that meters the airflow, on the sensor, broke off. So I just put it all back together. Started it up and runs just the same except now I have a code saying the MAF is completely bad (obviously). And the old MAF code (something about not having the right amount of air or something) is gone. Any input on this? I'm gonna find a MAF online and buy it since they are ridiculously expensive from the dealer and parts store that carry OE benz parts.

As for the o2 code, I found a leak in my header on the seam just before the o2. So I'm guessing that's what that code is for. So I'll get that repaired and clear that code.

As of now, I can drive the car and if I shift early, without boosting too much, it runs like normal. Idle stays between 800-1200 sometimes peaking to 1500 for a second or two. Just stays jumping around at idle no matter what.

 

$1000 car....put a thousand into it, waddaya got?
a 2 thousand dollar $1000 car.

Regarding MAF's. I recently purchased a Bremi (claims to be the OEM for many mfg's_
and so far, so good. I have 2.3L it was $100.
Stay away from ebay MAFs.

Disconnecting MAF was a good troubleshooting idea...no, actually the car will run without it connected but of course throws a code. It uses some default map when it doesn't see it, so it's often suggested to disconnect it to see if problems go away.

Regarding $1000 cars, I've recently seen 2 C Coupes, (both 2002) for UNDER a grand, one says it has issues with the 'key' meaning oh crap, the EIS, which can't be fixed by a mere mortal and another with a blown head gasket.
I was tempted by the one with the blown gasket, but the guy never got back to me.
But then, that would likely be just the beginning. Throw an engine in for a grand...
and yup, a thousand dollar thousand dollar car.

I'm at 234K and no CEL's and NO MALFUNCTIONS shows on the MFD.
The AC works, even the sunroof....
a neglected car will have so many issues besides the obvious ones.
So I keep driving...
btw not sure where you live, but lately I've managed to get some bits from the Picknpull or cheap. Otherwise, she's probably be at the junker. Recirc air valve and shift module. New the parts woulda been $2200, paid like $60. Running good again.

 

lol $1000 dollar car!

I actually just bought an OEM MAF. Hopefully I'll get it by this weekend to test it out. I've checked the wrecking yards and there's no c230's available at the moment. The dismantling yards (where they pull the part for you) either don't have it in stock or don't sell it because they don't want to warranty it. Dumb, I know. I'm gonna also pull the cover tomorrow to check timing marks just so I know. I needed a MAF regardless since it was physically broken. I had a coupe before and wanted a sedan, but couldn't afford it. They go for $6,000+ here all day long. Typically 150k miles too. But I wanted the car to play with for awhile. The funny thing is, I have a cousin that works for Mercedes, but he's usually MIA and hardly responds lol

 

Just a quick update: my MAF should be here Saturday. So I'm looking forward to slapping it on and seeing if it'll fix my issues. Also, I checked my timing and all the marks are dead on. No slack in the chain either. So hopefully it's just the bad MAF that was causing problems.

 

Yet another update... New maf came in. Maf code is gone now. Idle is normal sometimes, doesn't shake at idle now but still jumps around from time to time. Definitely smoother acceleration, but still limited to 4k rpm while idling. Had the p0120 code so I ended up changing with gas pedal with no luck. BUT while driving today I noticed I could go a little above 4k. At that point (~4200 rpm) I heard a rattling coming from the intake side of the engine. So I'm led to believe my still standing p0120 may just be a bad throttle body. I'm going try to get the throttle body tomorrow if I get out of work early enough (complete 2003 c230 at the wrecking yard). Has anyone ever experienced the throttle rattle? I can't have someone rev it while I search for the noise because it doesn't do it without actually driving. On a side note, if I clear my codes the cel stays off. As soon as I rev it or drive it I get a misfire code, from one cylinder to all cylinder misfiring. Still driveable, just rough. I simple restart will go back to normal until I try to accelerate over 4k rpm. What I'm gonna do is have someone floor it with the key on, not started, and see how far the throttle actually opens.

 

1st off Id invest in one of those Icarsoft code readers.
Reading generic codes on a Mercedes... just don't cut it.
I pulled my hair out with a too lean code, P0171 finally read it with SDS (and payed $40 just to do that) and it said the MAF was SHORTED. I did have a couple bad hoses too but in the end it really was the MAF.
I discovered there's this ICarsoft thing for like 100 bucks that reads the Mercedes specific codes. You can't change settings like SDS. I do need one of these....

Have you replaced the plugs yet? Sounds like whoever had this just didn't do the maint. Also kinda sounds like a plugged cat. But until you do the other stuff.....

 

thanks I'll check into the icarsoft. So far here is what I've done and found: replaced maf, replaced throttle actuator, replaced gas pedal (tps), checked plugs (haven't changed them), checked cat on both ends (used a camera), checked pre cat, and checked coils (pulled individuality to see if they changed idle). My cat looked good, I was able to pass smoke through them, no broken pieces that I could see. I found a missing vacuum line come out of the supercharger by the throttle body, reconnected that. I also found "cl fault" on my scanner live data last night. When I first drive the car it'll go above 4k rpm followed by a major loss in power in 2nd usually accompanied by misfire codes on all 4 cylinders. Restarting the car fixes this. If I shift at 3k rpm or under, it drives fine with little power loss until I get into higher gears. It seems like each upshift renders more power loss. Gonna do another smoke test hopefully today and see if there are more vacuum leaks and also look into the cl fault.

 

Replace the plugs! May look good but....
Every time I start getting misfires, I replace the plugs and all is well again...
I spent a lot of money replacing coils in the past, but in the end it was the plugs.
They don't last as long as advertised, will look fine, but seem to short or something and put a strain on the coils.
Also are any codes related to the Secondary air blah blah...
normally asipirated benz's have an electric pump, but ours has
a 2nd throttle body for the supercharger which apparently on the 1.8 sit under the supercharger.
Called a recirculating air valve.
Sometimes you have to do a reset which is easy on the 2.3, it's accessible by removing the air cleaner.
On yours you will need SDS to do it.

What are current codes?

 

Ok, I'll order some spark plugs and change those out asap. I just assumed because they were all the same and correct color (engine running good according to spark plugs) that they were fine. But I'll definitely just change them out. Here are the list of my current codes, but keep in mind the codes change a lot. For awhile I only had misfire codes on all 4 cylinders. Now I have 5 codes, only 3 of which are misfire codes...

Stored codes:
P0301 "Cylinder 1 misfire detected"
P0304 "Cylinder 4 misfire detected"
P0108 "Manifold Absolute Pressure/Barometric Pressure Circuit High" (Replaced a bad MAF, now I get this code)
P0303 "Cylinder 3 Misfire Detected"
P0130 "O2 Sensor Circuit Bank 1 Sensor 1" (I assume this is because I have a cracked header)

Pending codes:
P0120 "Throttle/Pedal Position Sensor/Switch A Circuit" (Replaced the pedal TPS and the throttle actuator)

 

Oh also I noticed that when viewing my live data, I have "CL Fault" on Fuel system. I started the car cold and checked it this morning again and when I started it, it was in "OL" (Open loop), then about 20 seconds later it went into "CL Fault" (Closed loop fault).

I'd be more than happy to post any or all my live data info if it'll help.

 

Just a shot in the dark here - have you checked the infamous $12 hose? There is a recall on this so if it was never done you may be able to have the dealer take care of it for free.

Here's a DIY if you want to check it out for yourself:
https://mbworld.org/forums/c-class-w...placement.html

 

Thanks. I actually saw that recently and checked it while I had the air box off. Looked good and didn't see any tears. I also just did a smoke test and a fuel pressure test. No vacuum leaks and my fuel pressure held at 54psi with fuel pump on, not running. After starting it, fuel pressure stayed the same. Revved it to 4k rpm (limp mode rev limiter) and pressure jumped a little but still 54-56 psi. Psi drops to 50psi at about 25-30 min when I turn the key off.

 

So thinking I have bent valves... Compression test netted me 115-127 for all cylinders.

 

Any other ideas?

 

What's your budget and time-frame for this car?
How much do you have left in your budget?

 

No budget and no time frame. But if the budget proves to be more than the car is worth, I'll just sell it for scrap.

 

The basic resale value of that car is not worth the needed cost to fix it. It never was.
Imho, simple searching before you bought the car would've indicated that the engine very likely needed a rebuilt/new cylinder head.


The "value" of the car is the "value" to a person.


To me, the value of my 2005 C230K Red Coupe with the body/frame/interior all in Very Good to Great shape, *GREATLY EXCEEDS* the "value" of a 100% brand new car, from the factory, with the full warranty, that costs ~$15,000. There are a few good new cars in that price range.

Yes, I'm putting my money where my mouth is. I'm not that far from that now. And, I haven't even touched the wheels/tires/etc.

To me, replacing the cylinder head, and doing a restore/enhancement is part "yawn - done that a zillion times" and part "NEW TOY/STUFF/PLAY-THING - LET ME AT IT!".


Fwiw, try Seaform. Do a search. Imho, nothing to loose at this point.
Imho, unless someone has a "thing" for a car just like that (like me and my search for my Red C230K Coupe), then that car/engine is only good for parting out items, and then scrap metal.

 

Makes sense. I have no problem replacing the cylinder head. Hell if that has to be done I'll just rebuild the entire thing. It's the not knowing for sure part that is bugging me. I was actually excited to do the head swap + all the internal parts. Had my guy at the machine shop ready for me to buy a head and drop it off. But now I'm not sure the head is even the problem. That's all I wanna know at this point lol.

 

I don't know how the valves could be bent without jumping the chain, but the 03-04
1.8L had an issue with the head, that caused carbon buildup, and then
low compression. People have litterally fixed the cars with a seafoam treatment, but if left too long in this state the valves get burnt.

Well, a can of seafoam should be next on your list. Well before delving into the expensive stuff.
Next project, pick up an 02. Bigger engine, more power and less problems.
They are noted for leaking at the #4 cylinder, which mine started doing 80K miles ago...
sadly I haven't fixed, no place to work on it, but the car keeps running.
If I keep it, I may just throw another engine in.