[Joemckna]

Haven't posted in awhile. First off, just want to thank all of you for the wealth of knowledge from members that's on this site. I've advoided countless inflated dealer repair costs by following threads and doing it myself. Thanks :thumbsup:

I've been dealing with the MAF sensor problem that I'm learning/reading is a hot topic. I have the same issue.. I cleaned the sensor and removed as much oil from the system a year ago when I first started noticing poor engine performance and an engine light. Took the car to do the dealer and was given the OBD codes and was given a big estimate for the repair which includes replacing the PCV valve and basically the entire MA system. Doing it myself, luckily the cleaner worked, light went off, car ran great afterwords, and the car was trouble free for another year.

Light came back on months back and rather then returning to the dealer, I took it to a shop for OBD codes(see if they were the same from last time) and to see if it would pass VA emissions. It failed.. OBD codes are;

P0170 Fuel Trim Malfunction(Bank 1)
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
P0300 Random/Multiple Cylinder Misfire Detected

I cleaned the MAF sensor again(oil was on sensor again) and cleaned as much of the oil out of the system as I could. Car ran much better, check engine light did not go off. This time around, I forgot to disconnect the battery. Haven't ran the car much since the repair. How long might it take? Should I follow the procedure for disconnecting the battery to reset the light? If it persists would you guys recommend replacing the MAF sensor?

What about the root? Has it been determined that the presence of oil in the system is in fact due to a bad PCV valve? If so, how difficult is it to replace the PCV? Anyone done it and if so do you have instructions? I have not used K&N filters by the way.. Thanks in advance!

 

[marvinstockman]

If car is a 96, you might have a bad wiring harness.

 

[Andrzejek]

I would recommend getting a good OBDII scanner, that will read and reset your codes. Check all vacuum lines. Clean the PCV. One of the lines must be blocked, as you should not be getting oil in your air box. I have not seen a drop of oil in my air box, with 170K miles on the odometer. A bad MAF sensor will throw a misfire code under medium/heavy acceleration. -- guess how I know...

 

[bl665]

The fuel trip code could be a bad gas cap as The Monitor does check to see if the pressure has dropped.

Why is your car Misfiring ??? Maybe a coil out on 4 (if you have inline 6 There is a coil pack on 2 4 and 6)

1 goes to 6
2 goes to 5
and 3 goes to 4

My car use to shake it was a bad coil on 2

I'd suggest new wires too as these can cause random codes (not sure about yours though)

Also check in the chamber of spark plug. See if there is a pool of oil this has caused these misfires. On my friends crown vic as well as a few Mercedes. I have seen this.

I believe the last code stated matches with the two above it.


As for everything else It might be good to get a $132.00 scanner from Wally world (one year warranty)

That way you can see which monitors have run and which ones have not.

This way you can pinpoint the problem more adequately. Each system is set up into categories which relate to certain parts and sections to your vehicle.

If you have time try to change coil packs onto lets say 2 or six, reset battery and run your car until the freeze frame DTCS pop up (about 60 miles) and see if the code changes to cylinder 2 or 6 depending on which you choose.

Hope this helps Pm me if you have any questions about what I said lol

 

[Joemckna]

Whoa, information overload!!! Thanks for the food for thought. Do you have a link for a good OBDII?

After doing a lot of reading, a good starting point might be the mass air flow sensor. I ended up cleaning it again with MAF cleaner and this time I disconnected the battery to reset OBD/check engine light. Light finally went off, for about 80 miles. Car ran good. Light came back on... I reset OBD again by disconnecting the battery and took it down to the shop for a retest. Car didn't throw any OBD codes this time with the light off, although he wouldn't pass me because the evaporative system showed "incomplete" on his monitor He told me that I had to let the car sit with over half a tank of gas for 10 hours, drive 4-5 miles, and then bring it back in for a retest. Woke up the next morning got in the car and it ran like crap...

I found MAF sensors ranging from $75-$400. Why such a big gap in pricing? I was told to posibly replace the PCV valve. I haven't checked it, nor do I know how to get to it. I'm handy though.

The fuel trip code could be a bad gas cap as The Monitor does check to see if the pressure has dropped.

Why is your car Misfiring ??? Maybe a coil out on 4 (if you have inline 6 There is a coil pack on 2 4 and 6)

1 goes to 6
2 goes to 5
and 3 goes to 4

My car use to shake it was a bad coil on 2

I'd suggest new wires too as these can cause random codes (not sure about yours though)

Also check in the chamber of spark plug. See if there is a pool of oil this has caused these misfires. On my friends crown vic as well as a few Mercedes. I have seen this.

I believe the last code stated matches with the two above it.


As for everything else It might be good to get a $132.00 scanner from Wally world (one year warranty)

That way you can see which monitors have run and which ones have not.

This way you can pinpoint the problem more adequately. Each system is set up into categories which relate to certain parts and sections to your vehicle.

If you have time try to change coil packs onto lets say 2 or six, reset battery and run your car until the freeze frame DTCS pop up (about 60 miles) and see if the code changes to cylinder 2 or 6 depending on which you choose.

Hope this helps Pm me if you have any questions about what I said lol

 

[Joemckna]

I would recommend getting a good OBDII scanner, that will read and reset your codes. Check all vacuum lines. Clean the PCV. One of the lines must be blocked, as you should not be getting oil in your air box. I have not seen a drop of oil in my air box, with 170K miles on the odometer. A bad MAF sensor will throw a misfire code under medium/heavy acceleration. -- guess how I know...

How do I clean/check the PCV and check the lines? I was told the PCV valve might be a good starting point and is the root of the problem. I'm still trying to get my bearings mechanically with this car. I'm used to repairing carb engines and farm equiptment. If you point me in the right direction, I'm sure I can figure it out. Each time, I've cleaned/removed oil where I could including the mass sensor and re-installed, the car stopped throwing codes and ran a hell of a lot better. Although this time, I'm not having any luck. Light keeps coming back. Found a wide range of mass air flow sensors on-line, various prices. Found one new for $75. Is there a difference in quality? Should I go with a Bosch sensor for $200? Thanks!

 

[marvinstockman]

First, have you thought about getting the Bentley or the Mercedes manual for your car?

If your PCV is OK, you're probably going to have to run a heavier grade of oil, say 20W50, or maybe add a can or two of STP to see what happens with the blowby.

 

[Mercedes mechanic]

Each time, I've cleaned/removed oil where I could including the mass sensor and re-installed, the car stopped throwing codes and ran a hell of a lot better. Although this time, I'm not having any luck. Light keeps coming back. Found a wide range of mass air flow sensors on-line, various prices. Found one new for $75. Is there a difference in quality? Should I go with a Bosch sensor for $200? Thanks!

Don't buy a sensor just yet. There are procedures for checking your parts. Like a ohm test for the plug wires, resistance test for the coils and a whole battery of tests.


For example:

1. Check flow out of the vent hose on the valve cover to make sure vent in valve cover isn't blocked, causing excessive flow out of the crankcase vent. That could be causing oil vapors to be pushed into the air intake system.

2. Check the fuel pressure, spec is 54-60 PSI.

3. Check for false air leaks, vacuum leaks or boost leaks.

4. Read the Mass Airflow (MAF) output on scanner data stream while driving. At idle in Park/Neutral (P/N), the output should be 3.0-4.5 grams/second (g/s) or 8-13 kilograms/hour (Kg/H). At 2000 RPM in P/N, 8-12 g/s or 25-40 Kg/H. Drive vehicle at 40 MPH, then apply wide open throttle. Reading on the scanner should immediately go to 120 g/s or 440 Kg/H.





But, and here is the bad news, your kompressor is leaking oil on the inside seals, flooding the MAF with oil. Thats why you cant keep it clean.

 

[Andrzejek]

Just my two more cents here regarding the MAF large price differences -- I did buy one of those cheap MAF sensors a year ago, and it's been working just file. Short/long term fuel trim is running close to zero with this MAF.

Also, I highly recommend getting a decent OBDII code reader that shows codes /pending codes / readiness codes / live data. That way, you will not have any surprises when you visit your smog shop.

 

[Joemckna]

Don't buy a sensor just yet. There are procedures for checking your parts. Like a ohm test for the plug wires, resistance test for the coils and a whole battery of tests.


For example:

1. Check flow out of the vent hose on the valve cover to make sure vent in valve cover isn't blocked, causing excessive flow out of the crankcase vent. That could be causing oil vapors to be pushed into the air intake system.

But, and here is the bad news, your kompressor is leaking oil on the inside seals, flooding the MAF with oil. That's why you cant keep it clean.

I see three lines coming off of the oil separator, one of which looks to be coming from the valve cover. I noticed that there was oil on the outside of the oil separator and on the lines connected to it. I pulled the oil separator and it was full of oil. The oil separator hose(that also receives a rubber line from the dipstick) broke while I was removing it. I found a replacement on-line luckily.

Do you have a picture or an exact location of the crankcase vent valve? I'd like to check this part, but have been unable to locate it based on the descriptions given. Anyone have a picture?

How/why is the Kompressor leaking oil on the inside of the seals? I thought the root(as you were saying) was involved with the vent hoses & valves?

 

[Mercedes mechanic]

How/why is the Kompressor leaking oil on the inside of the seals? I thought the root(as you were saying) was involved with the vent hoses & valves?

Age, lack of on time oil changes, milage take your pick. That part is all a guessing game.


Someone will put up the location diagram, but I dont have one ATM.

 

[bl665]

Whoa, information overload!!! Thanks for the food for thought. Do you have a link for a good OBDII?

This is the one I got with a year warranty. It works fine. Read the manual before using though !!

Equus 3100 Innova CanOBD2 Engine Diagnostic Tool - Walmart.com

After doing a lot of reading, a good starting point might be the mass air flow sensor. I ended up cleaning it again with MAF cleaner and this time I disconnected the battery to reset OBD/check engine light. Light finally went off, for about 80 miles. Car ran good. Light came back on... I reset OBD again by disconnecting the battery and took it down to the shop for a retest. Car didn't throw any OBD codes this time with the light off, although he wouldn't pass me because the evaporative system showed "incomplete" on his monitor He told me that I had to let the car sit with over half a tank of gas for 10 hours, drive 4-5 miles, and then bring it back in for a retest. Woke up the next morning got in the car and it ran like crap...

I found MAF sensors ranging from $75-$400. Why such a big gap in pricing? I was told to posibly replace the PCV valve. I haven't checked it, nor do I know how to get to it. I'm handy though.

I can say that to check hoses like the rubber ones. Squeeze them and see if they are stiff. (have engine cold) Most likely i'm sure if they have a little of elasticity they should be ok. Unless they have giant cracks or are super stiff and hard, which would be obvious.

The vacuum lines that run off EGR, shutoff valve, etc. Are about 1/2 thick and most of them should be plastic. Really brittle plastic. you buy hose at Auto zone for cheap and might as well replace while your involved.

Give me your E-mail and I can send you A Vacuum diagram. Just to make sure everything is going to the correct place.

Don't buy a sensor just yet. There are procedures for checking your parts. Like a ohm test for the plug wires, resistance test for the coils and a whole battery of tests.

For example:

1. Check flow out of the vent hose on the valve cover to make sure vent in valve cover isn't blocked, causing excessive flow out of the crankcase vent. That could be causing oil vapors to be pushed into the air intake system.

2. Check the fuel pressure, spec is 54-60 PSI.

3. Check for false air leaks, vacuum leaks or boost leaks.

4. Read the Mass Airflow (MAF) output on scanner data stream while driving. At idle in Park/Neutral (P/N), the output should be 3.0-4.5 grams/second (g/s) or 8-13 kilograms/hour (Kg/H). At 2000 RPM in P/N, 8-12 g/s or 25-40 Kg/H. Drive vehicle at 40 MPH, then apply wide open throttle. Reading on the scanner should immediately go to 120 g/s or 440 Kg/H.


But, and here is the bad news, your kompressor is leaking oil on the inside seals, flooding the MAF with oil. Thats why you cant keep it clean.

Exactly stated lol Go and get the right equipment to test your parts. Also I'd personally like to know what model your working with since above it sated you had a kompressor. I'm not sure what I'm helping with exactly.

Another thing you could do to help us would be to take plenty of pictures and post them so we know exactly what were dealing with.

 

[Joemckna]

Car is a 1999 C230 Kompressor

Got some time under the hood last night. I found a deal on a bundle of parts and was able to snag a new MAF sensor, oil separator, crank case vent valvle. and a few pre-formed lines. I checked as many of the vaccum lines as I could. I also checked for cracked-brittle lines, and also made sure that all the air/breather hoses were connected properly. I didn't know this until last night, but I popped the air cleaner box open and a found a small gray filter inside around the output tube. It was heavily deteriorated and full of oil. It was a pain to get off, but I replaced it.

Somehow or another, I finally found the elusive crank case vent valve. Yes, this car does have one. It's on the driver side, side of the engine right near the exhause manifold under the fuel rail. I somehow or another got my hand on it. Both small diameter lines that "T" off it, were brittle and sheared. I managed to the valve off. It was full of oil, but I'm not entirely sure if it was obsturcted? The poor state of the lines, I'm willing to guess this needs attention. I'm going to pick up new lines, and I'll see if I can literally get a new one on there one handed. 0 room to work with. I'll need a mirror to see the tips where the lines connect.

I'll keep you guys posted, thanks again. Joe

 

[bl665]

Along with the E-mail I sent I also wanted to mention to make sure all the lines are connected to the right parts

 

[Joemckna]

Didn't Work.....

I'm going to check out the OBD diagnostic tools at Walmart later on today. I took a look at the Equus line on-line that was recommended and they seem to go hand and hand with what I need. I'd be interested to see if the car is throwing the same codes.

I ended up getting the car back together and managed to slip a new crank case ventilation valve(PCV) on with new vacuum lines. It took an hour, with a mechanics mirror, long needle nose pliers, and a friend with a long skinny arm. I ended up jacking the car up and my friend was able to get his arm past the starter to where the tips are located on the engine. It wasn't easy...

Got the whole thing back together and the car started lagging/hesitating heavily from 1st into 2nd. It didn't work itself out and I was unable to put the needed miles on the car to work the new MAF sensor in. Something is wrong, again. After 20 minutes, check engine light came back on. I checked again for vaccum leaks but couldn't find anything. I crossed my T's and dotted all of my I's, but something is still off. I was curious to see what what would happen if I switched the new MAF with the old MAF. Car stalled and chugged when I re-installed the old MAF.

What's a good, simple way to test the MAF sensor? I want to eliminate the possibility of this one being defective. It was a cheap $70 replacement.

I took the car to my mechanic, they sat on it for 3 days and I was told yesterday "we have no idea as to what's wrong with your car." I was surprised to say the least. These guys can be selective and just became an emissions test location. Previously, they wouldn't touch emissions related issues. It's a Midas. They did check the fuel injectors and found no problems. They checked the coils and said there were no issues. They also told me they sprayed carb and choke cleaner on the connection where the vacuum lines are to see if they could locate a source of un-metered air, they didn't detect a spike and couldn't find a leak.

I'm going to triple check all of the vaccum lines again. Might pick up an OBD, and will look to see how I can check the MAF sensor. Should I be looking at other sources, o2 sensor? EGR valve etc... FYI: I seem to get somewhere in regards to the way the car runs and drives each time I get near the MAF. Thanks in advance :thumbsup:

 

[Joemckna]

Can't find any problems, and yet the car still chugs and hesitates. Didn't find any leaks. I don 't know how to test the MAF, since it's cheap it might be defective.

Anyone know of a good shop in Northern VA? I was told that E&M garage in Alexandria is pretty good. I'm tired of this car already. It's currently for sale..:surrender:

 

[Sunny_atl]

1999 MB C230 Kompressor Frustrating P0170 Code Please Help !!

Hey guys,

I have 1999 MB C230 Kompressor with 102k miles car runs perfect no driving issue or idling issues at all but last 3/4 days just dealing with P0170 Fuel Trim Bank 1 issue, after reading different DIY Benz forms i have done so far is below.

1- Check all vacuum pipe / hoses / harness / wires seems every thing fine. erase the code with OBD scanner after 35 miles CEL came back with same P0170 code.

2- I opened air filter box found little bit of oil on air filter clean it,erase the code with OBD scanner after 28 miles CEL came back with same P0170 code.

3- Clean MAF with CRC MAF cleaner including hoses connected with MAF, no oil on MAF but clean it thoroughly with CRC MAF cleaner i never touched MAF with q-tip etc. etc. erase the code with OBD scanner after 18 miles CEL came back with same P0170 code.

4- Cleaned throttle body including connected hoses with it, throttle body was little oily clean thoroughly with CRC cleaner as well, erase the code with OBD scanner after 25 miles CEL came back on with same P0170 code.

right now i have check engine light on i took LIVE DATE with OBD II scanner which is below for your expert opinion.

LIIVE DATA:

DTC_CNT: 1
FUEL SYS1: CL
FUEL SYS2: N/A
LOAD_PCT(%): 12.9
ECT (C): 90
SHRTFT1(%): 1.6
LONGFT1(%): 32.0
MAP(kPa): 32
RPM (/min): 755
VSS (km/h): 0
SPARKADV: -13
IAT (C): 37
MAF (g/s): 2.41
TP (%): 2.7
AIR_STAT: OFF
O2SLOG BIS12--B2S----
02B1S1 (V): 0.780
SHRTFTB1S1 (%): 0.8
02B1S2 (V): 0.520

FREEZE FRAME DATA:

DTCFRZF: P0170
FUELSYS1: CL
FUELSYS2: N/A
LOAD_PCT (%) 18.8

NOW my brain is completely drain of ideas, the only answer i can think of to resolve P0170 is change MAF sensor but before putting $200 in to MAF sensor i need your expert opinion about the issue i have, my TAG renewal is due CEL light is ON and EVAP monitor is incomplete and i doubt it will pass emission / smog test too ?? will it pass or no ?

Thanks in advance.

 

[Joemckna]

Sunny, you could try posting your own thread.. I didn't get anywhere with these guys here relating to my problem.

Hey guys,

I have 1999 MB C230 Kompressor with 102k miles car runs perfect no driving issue or idling issues at all but last 3/4 days just dealing with P0170 Fuel Trim Bank 1 issue, after reading different DIY Benz forms i have done so far is below.

1- Check all vacuum pipe / hoses / harness / wires seems every thing fine. erase the code with OBD scanner after 35 miles CEL came back with same P0170 code.

2- I opened air filter box found little bit of oil on air filter clean it,erase the code with OBD scanner after 28 miles CEL came back with same P0170 code.

3- Clean MAF with CRC MAF cleaner including hoses connected with MAF, no oil on MAF but clean it thoroughly with CRC MAF cleaner i never touched MAF with q-tip etc. etc. erase the code with OBD scanner after 18 miles CEL came back with same P0170 code.

4- Cleaned throttle body including connected hoses with it, throttle body was little oily clean thoroughly with CRC cleaner as well, erase the code with OBD scanner after 25 miles CEL came back on with same P0170 code.

right now i have check engine light on i took LIVE DATE with OBD II scanner which is below for your expert opinion.

LIIVE DATA:

DTC_CNT: 1
FUEL SYS1: CL
FUEL SYS2: N/A
LOAD_PCT(%): 12.9
ECT (C): 90
SHRTFT1(%): 1.6
LONGFT1(%): 32.0
MAP(kPa): 32
RPM (/min): 755
VSS (km/h): 0
SPARKADV: -13
IAT (C): 37
MAF (g/s): 2.41
TP (%): 2.7
AIR_STAT: OFF
O2SLOG BIS12--B2S----
02B1S1 (V): 0.780
SHRTFTB1S1 (%): 0.8
02B1S2 (V): 0.520

FREEZE FRAME DATA:

DTCFRZF: P0170
FUELSYS1: CL
FUELSYS2: N/A
LOAD_PCT (%) 18.8

NOW my brain is completely drain of ideas, the only answer i can think of to resolve P0170 is change MAF sensor but before putting $200 in to MAF sensor i need your expert opinion about the issue i have, my TAG renewal is due CEL light is ON and EVAP monitor is incomplete and i doubt it will pass emission / smog test too ?? will it pass or no ?

Thanks in advance.

 

[Joemckna]

Fixed it

I fixed the problem. I never got a conclusive answer from anyone here or the other 3 mechanics(including the dealer). Not that I care, I sold the damn thing and my nightmare with this car is over.

I replaced the PCV valve, myself. If you have a friend with skinny hands and long arms, as well as a mechanics mirror and a flashlight. You can do the job yourself. I also replaced the oil seperator(my best guess for the oil), I cleaned all of the oil out the entire intake system, and replaced the air filter.

I had purchased a cheap remanufactured MAF sensor for $75 to replace my faulty MAF. After spending weeks on this problem and getting no where( rough idle, backfiring, misfire OBDII codes), I still got no where. All signs pointed to the MAF. I sent it back and ordred a brand new Bosch MAF for right around $250.

Right after installing the MAF, the engine ran like a top. I reset the OBDII codes, and passed emissions the following day. Car ran like a top. If you have a high mile C230 and the original MAF is installed, check for oil, clean if needed, but consider purchasing a quality replacement. Makes a huge difference.

I sold the car immediately after and have washed my hands of this problem, the high priced repairs, and more importantly a high cost to own, highly depreciated MB. Bought another car, I'm happy. Hope some of this might help a few of you. Later all...