Hey all,

I have a problem which i cannot figure out for some time now.

1999 w210 E55 AMG with 116k miles

Replaced spark plugs 30k miles ago.
Replaced MAF 30k miles ago.
Replaced Air-filters 30k miles ago.
JUST replaced the spark plug wires and tried to clean the MAF with MAF cleaner.
JUST did an oil change.
JUST did a tranny fluid change.

Here is my problem that started about 2 months ago and has gotten worse. It used to only happen pretty rarely, now its every time...

Engine idles okay. As the engine RPM goes past around 3500-4000 RPM under load, my engine throws misfire codes. but nothing else. Even when i put the trans in first, then slowly reach 3500-4000 rpm (practically no load) i have the same problem. My engine then runs really poorly (fewer cylinders) until i stop and restart the engine.

I unplugged the MAF and experienced the same issues. When i cleaned it i didn't notice anything different.

Things I'm looking at:
Coils,
O2 sensors,
a new MAF,
knock sensor,
camshaft sensor,
crankshaft sensor (prob not the last 3).

Any help before i have to throw more money into this thing???

Thanks in advance,
-nick

 

It's possible it might be the coilpacks. Although i would just take it to an independent shop who has a DAS machine and really take care of it instead of burning more benjamins on it. Just my 2 cents.

 

Could it also be my injectors?

And if it is the coils, is there a way i could test it? it seems like i have a failure at High RPM indicating a high load on the coil. So i don't think i would be able to see anything wrong by measuring resistance when engine is off. BUT i'm willing to try. does anyone have resistance numbers for our coils?

 

+1 sounds exactly like a coilpack
from what i remember i think it does give you the exact cylinder # misfire with a OBDII code, once you have that you can further test it by moving the bad coilpack around in a different spot and see if you get misfire at the "new" cylinder

code reader first though, it's men's best friend

 

The coil packs retainer clips on these cars get brittle from the heat over time. It is common that they can even break off. While the clip that powers the coil pack may still be connected even with its broken. Over time it can come loose.

Symptoms of this are.. Normal driving at low RPM's and slow speeds (not all the time though). Then when you get into it the car sputters and shakes. You would think you messed something bad up. It can feel that bad.

to check this all you have to do is check the wire that runs to the top of the coil pack. Make sure they are pushed all the way down. Check and see if you have any broken retainer clips of the power wires.. OBDII will tell you where the misfire is, cylinder wise . I would also look at any parts recently replaced too. Sometime these plug wires are a pain to seat down all the way.

 

Yeah, I'll double check the connecting clips, but I didn't have any that were broken. I ended up taking out the coils when i did the spark plug wires. I went ahead and ordered 2 coil packs from autohausaz.com and will be messing with those when they get here-- probably early next week.

When I got the codes read, it was a bunch of 03xx codes (random misfires) on like all of my cylinders. so I'm not sure which ONE is the culprit, hopefully its just 1 at the moment. I got 2 coil packs for future replacement for a second failure.

BTW, anyone know where to get the screws for the coil packs (the T27 bolt?) I lost one some time ago somehow when i was doing a spark plug job 2 years ago.... i know, i'm a moron. I'm hoping that i haven't damaged any wires from the vibration, although whenever i pop my hood the coil is still in its seat.

For now, i just drive like a grandma... and I get passed by ford pintos lol.

 

or is it a t30 bolt, i forgot. anyone?

 

ok bad news (for me at least). Its not the coils. What do you guys suggest next? I listened to my injectors and can hear each one individually firing so i think those are fine.

any clues?
-nick

 

Can you post the exact string of codes? Which cylinders are misfiring exactly?

How does the car run, other than the codes? Rough, slow, stuttering, fast?

Does it ever stall? CPS seems like a possibility.

 

from the last time i got the codes read, all but cylinder 2 was misfiring. but i believe that was due to me trying to drive in traffic with the engine running in limp home. and i could tell i was making it worse.

I feel like the problem has stayed the same over the past week. cant go over 3.5k-4k rpm. a bit rough idle. Power is definitely gone. Never stalls tho.

what would be the symptoms of the Crankshaft position sensor and the Camshaft position sensor. I hear a lot about the CPS, but not the camshaft one.

My car always starts and has no trouble, even when it is damn hot outside. i use the AC and temps get to about 218F sometimes and she starts just fine.

I should be getting my own OBDII reader tonight and hopefully i will be able to get more details from my car.

 

I also posted in the general w210 forum and Ohlord mentioned that it might be plugged cats. When i rev my engine, it does sound different from before when it ran well. it now, actually, sounds deeper, more growly, but the power isn't there. really dont know what that is about.

I couldn't diagnose if my cats are in fact plugged. I had some one rev my motor while i felt the pressure of my exhaust. but both banks seemed to have equal pressure. So they are either BOTH plugged or not.

I ordered new o2s but that was for future service. I might try and run without my o2s plugged in and see if im getting fouled readings from them.

 

When was the last time the fuel filter was changed? Have you pulled plugs and looked at them? If so, what do they look like?

 

yeah, fuel filter was changed 30 k miles ago same with plugs. I pulled one plug, it looked clean, the gap was .040 from what i measured. but i didn't pull the rest. I think i will sometime this weekend, but i dont have time in the immediate future.

 

update:

So ended up getting a nice OBD II reader which gives live data output. Figured out that my bank 2 cylinder set (drivers side) runs lean as RPM goes up under load causing bad spark knock which is definitely audible with the windows down or up. the numbers seem to be within reasonable bounds when engine rpm is around 2k.

from idle, both short term and long term fuel trims are at around -3.5 (dont know the units) on B2, whereas B1 is around -0.7 - 0. indicating a RICH idle on bank two. However, when i accelerate both fuel trims on both banks go up as they should (to widen the injector time), but a huge delta grows between b1 and b2 as follows:

B2 B1
-3.5 -.7<---idle
2 4
3 7
4 9 <---~3500 rpm

This gap tells me that B2 runs extremely lean in comparison to B1. and you can hear the spark knock (not rod knock) just before the knock sensors catch it and throw the code. if im' on the gas too long, it will flash the CEL and run on 4 cylinders.

I replaced my aged and fouled O2s and now things definitely run better, but the main problem still exists. I def have better power, even with my engine running poorly.

I pulled the plugs and they all look fine, if anything ALL of them seem to be running a hair on the rich side. Not ONE plug (or set of two) appeared to be in bad shape.

Furthermore, i tried seeing which misfire code popped up first, which was tricky. I had to let off the gas as soon as i saw the light come on, else i would get lots of other random misfires. Cylinder 6 came up 4 times in a row. So i'll be taking a closer look there. Since i'm running lean (short term and long term fuel trim do not go as positive as bank 1) i'm thinking my next step is faulty injector(s).

Gah this car is driving me insane...

 

I had similar misfires until i bought a new MAF and reset the ME and EGS adaptations thru CarSoft...Problem solved. Cars runs like new...gas mileage went down but car pulls like a champ now and idle is very smooth. A MB mechanic gave me that tip. Always reset the ME when replacing the MAF. The misfire seems to creep up every 2 years or 25-30k. I am on my second MAF and my car has 62k on the clock.

I believe if you unplug the battery overnight, it will reset the fuel trim mappings just like carsoft.

Anyway...This has been my experience I thought I share with you.

GL

 

Ok i'll try disconnecting the battery tonight.

I used to have a bad MAF 30k ago. when I unplugged it back then and ran the car it was perfectly fine. never misfired without the MAF. the only thing that my car did without a MAF was sometimes stall when stopped.

Now, when i unplug my MAF, nothing changes. I even drove it around to see if it was going to stall, but it never did either. I still have the exact same symptoms described above. So im hesitant towards buying a new MAF. I may go that route if i'm still stuck by the end of this weekend.

 

Battery DID reset the fuel trims. But alas,the problem is still there. I'm going check the injectors and pull the intake manifold this weekend. Wish me luck lol

 

Hmmm. I'm still not convinced that your MAF is not completely fouled. I've read above you used MAF cleaner on the current MAF... That could compromise the sensitivity of the MAF or even render it useless.

PM me your address and I'll send you my last MAF which did not throw any codes but did produce a random misfire and rough idle. Disconnect battery overnight and put in my MAF to see if the problem exists or at best acts differently than your current MAF. To me, if you car acts the same with or without a MAF, I would say it is not doing anything at all The ECU could be in a default MAF mode because it's not registering any measurements.

Ain't this fun!!!

 

pm sent!

 

If you haven't already sent the MAF, i wouldn't send it. I'm beginning to think it isn't the MAF because only HALF of my motor is running poorly.

Cylinders 5,6,7,8 are on Bank 2 which is the drivers side. I just realized this. i thought it was alternating with bank 2 holding the even cylinders, but it is not the case. this tells me that there is something on the drivers side which is contributing to my problem.

in no particular order:
1.Injectors
2. spark plugs
3. coils
4. spark plug wires
5. plugged catalytic converter
6. burned exhaust valve(s)
7. fuel system (55psi check)

not numbers 2,3,4,7 for sure since i'v checked those components and replaced them recently

Most likely NOT my injectors since i highly doubt more than 1 has failed bad enough to do any of what i'm seeing. and the plugs didn't reflect any of that.

might be number 6. but i also doubt it on this motor. or at least i'm hoping that isn't the case lol.

that leaves number 5. which seems plausible considering it all happens on one side of my motor. exhaust sounds funny/different from the last time i remember it running correctly. I'm experiencing slightly higher engine running temperatures, upwards of 220F+ which is about 15-20F higher and has not happened to me since my fan clutch failed 2 years ago.

my MAP is about 9 inHG at idle speed. of which i need to confirm with a reference somewhere. but it seems low. if anyone can tell me what their intake manifold pressure is that would be awesome. I got my reading from the OBDII, not from an actual gauge.

 

Ok I'll hold off.

 

After Battery disconnect and reconnect I got same problem as described in above post and have been working to resolve issue over past days.

Its always when passing 3800-4000 Rpm then car runs 5 cyl, when getting real HOT issue gets worse and the car is almost unable to drive over 20 mph until cooled down.

Carsoft returns error ME Error 0300 and 0301, this indicating issue is on cyl 1 and so it seem at first eye, when pulling plug from coil egine idle remains same... running 5 cyl, when pulling from any other coil it goes down to 4 cyl, so first assumption is ignition issue on cyl 1, however that is not so...

Started in following way

1) Changed all 12 Plugs to new Original MB plugs..(cost a fortune) and set to 0.40, after reset I reset all adaption values and reset error in ME.

No Change same ME error when getting real HOT (within 20 min after start)

2) Changed all 12 Cables to new Q after marked parts.after reset I reset all adaption values and reset error in ME.

No Change same ME error when getting real HOT (within 20 min after start)

ME error is indication issues on Cyl 1, tried pulling the plug of when error apears and egine idle does not change, so its confirmed that something is making Cyl 1 to stop working.

3) Changed Ignition coil to new Bosch Coil, after I reset all adaption values and reset error in ME.

No Change, actually feels like its getting worse. So same ME error when getting real HOT (within 20 min after start).

Now I received again same ME error however also 2 other errors:

a) ME Error 0300 and 0301 (the always repeating error)

b) 0130 and 0150 O2 Probe signal not OK, Right side, voltage increase to low (this is one of the two new errors)

c) 0110 Air intake temp sensor, verify voltage and connections.

I then went for a drive with above issue ... and if I use carsoft live data when driving my Right O2 sensor is not returning any values but left is seems okay with constan changing values.

Question is now...is the issue with the ignition just something the ECU is making the car do like some limp program, cause I have changed all ignition parts and is the Real issue O2 sensor?

Really Need your guys to help here running out of cash to keep changing part after part...

 

UPDATE:

So I went on a limb and unscrewed the drivers o2 sensor (bank 2) to see if I could eliminate the possibility of back pressure from a clogged/plugged cat... SUCCESS!

I was finally able to rev my motor down the street to just a little over 5k rpm with no misfires. Kinda scary as it was pretty loud and the fuel line is RIGHT there being cooked by the exhaust lol. Sounded awesome, even if it was just 4 cylinders haha.

So now the question: Where can I find a good pair of High-Flow Metallic Cats to replace my PRIMARY cats? I'll end up deleting my secondaries and most likely put in an x pipe in its place. Also deleting the resonator. I have searched the forum for a good reference but came up with this link for high flows:

http://cgi.ebay.com/ebaymotors/Pypes...#ht_2907wt_939

But I would like to gather some opinions on other choices if you guys had purchased some good aftermarket high-flows for the primaries.

Thanks guys for all the other inputs, but especially congrats to Ohlord who initially suggested that my issue could be my cat (in another thread).

Anyways, Links to good high-flow metallic cats below please!!!

 

anyone???

 

bump