rilonprime

Disclaimer: I will send a free pizza to who ever can help me figure out what's wrong.

Hey There!

New to the forum, and a new w211 owner. I purchased the vehicle from a family friend, it's an 03' e320. Had regular service done by dealer, etc. However, when I got it, the engine mounts were totally dead, so I fixed that. Then, I started getting a CEL that (I forget the exact error code) said "Evaporative emission leak - very small leak". Figured it might be the gas cap, but after replacing it, the CEL still came on. Then, I end up ordering a new gas pump and seals for both sides of the tank. After installing that, the code went away, and I passed Smog!!

Several weeks later, I start getting another error code: "Oil level too high - remove oil"... this scared me. So I purchased a dip stick, which when I got it, showed the oil was too low. I put more oil in the engine, and run it for about a week, but the oil level warning was still there. Finally decide it's a faulty oil sensor, and when I go to install it, figured I might as well do it oil change.

This is when things start going wrong...

I remove 9 and 1/2 quarts of oil out of the engine. That was way too much. It turns out, the oil stick I bought was for a different engine!!

I measure out the correct oil, fill her back up, no "too much oil" warning anymore.

BUT THEN

I get a CEL. I check the codes, and THERE'S 9 CODES!!! WHAT THE HECK!

p0446 Evaporative emission system vent control circuit
p0335 Crankshaft Position Sensor A circuit
p0410 Secondary Air injection system
p0412 secondary air injection switching valve A circuit
p0444 evapoative emission system purge control valve circuit open
p0403 exhaust gas recirculation control circuit
p0135 02 heater circuit (bank 1, sensor 1)
p0141 02 heater circuit (bank1, sensor 2)

Some of these codes don't really make sense to start showing up at the same time, however I'm sensing the common denominator is something electrical.

I poked around the engine bay looking for loose wiring, and even unplugged and re-plugged the ECU. Still getting codes instantly, even after clearing.

I don't even know where to go with this... any ideas?

cetialpha5

How are the batteries? You have a main one and the backup SBC one. Low voltage can cause all kinds of weird problems or it could be the alternator/battery control module. Otherwise maybe a loose ground somewhere.

MattieIce

I agree. Maybe the alternator isn't fully charging the batteries. I would look there first.

rilonprime

Thanks for the lead... I'll take a look at the batteries later today. I know there is the main battery in the trunk, and another smaller battery under the cabin air filter. I'll see if I can test those.

I did pull out the big orange 40amp fuse in the SAM fuse box, and the ends looked toasted (however, the fuse was still intact)... I wonder if this is derivative of something else. I do notice that the air pump does not turn on at cold start, but the pump definitely works (I put leads from another battery - spun right up). I'm thinking it possibly could be a bad relay.

Thanks for your help here guys, I'll let you know how I fare.

rilonprime

Tested the batteries yesterday, they read 12v (and 14v while on), and replaced the 40a maxi fuse. CEL came back on, almost an hour after clearing.

jimbo1763

Same set of codes?

Plutoe

I'd start over--first clear all faults, run the car around---what faults return. Then post the returned faults.

MattieIce

I'm just spitballing here... What if the too much oil actually cooked the sensors or shorted a wire that fried all of the other sensors? Maybe replace one of the easier sensors, clear the code, and rescan to see if it pops up again. If it reappears, you know you have a different/bigger problem. If it goes away, you know the sensors just need replacing.

rilonprime

Yes, same codes. :/

rilonprime

Thanks for the responses, everyone. I've cleared my codes multiple times, and have been driving it daily. Still getting the same 9 codes as before.

I've been searching throughout the forums and online, and it seems that there's not one right solution to this... I've concluded that the air pump may be ground zero for everything else. I tested the airpump (thanks to a near-by battery), and the pump runs. However, the pump will not start when the engine is cold. I've checked the fuses and relays, and they all check out. I then thought it might be something wrong with the engine temperature sensor (thermostat?), but the water temperature gauge works on my dash, so I don't know if it would be that sensor.

bbirdwell

Put it on a Xentry or Star diagnostic system. The tests there will point you to the problems. You'll thank yourself later.

cetialpha5

Yeah, if you're been working at it for this long, try picking up a cheap code scanner that does MB specific codes. I got an X431 Launch EasyDiag Plus, about $58 on eBay. You probably have a bunch of other hidden codes.