Results 1 to 25 of 25

Thread: M119 low on power - suggestions?

  1. #1
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    M119 low on power - suggestions?

    Hello all

    My 500E is quite low on power and I am beginning to think there is something wrong with the engine. I've not had the codes read yet but the PO is a friend of mine (owned it for 8 years) and he said it was not producing near enough power compared to when he owned it. He now owns an E500, I've not driven his E500 for a while but seem to recall it is much quicker when I did a few months back. My E55 is a bullet in comparison but the M113 does have different character.

    There are no obvious mechanical issues other than I did have a rattle at cold start a few times. That seems to have gone away weirdly enough with no engine work done other than the rocker covers replaced.

    Hoping to take the car in tomorrow for a read of the codes and a compression test on each of the cylinders to rule out anything sinister. Any recommendations or areas to check while the car is in? I have replaced the MAF to a used but remanufactured unit and also the throttle body is dated 1997. I have not dropped the oil pan to check for guides. How about chain stretch? Again never really heard of them going bad. PO suggested the rattle is probably the chain tensioner.

    I have not replaced spark plugs or any of the ignition parts yet - plugs, distributor caps and rotor arms were changed around 1.5 years ago. Wires probably 3-4 years ago. Ignition coils never replaced in the last 10 or so years. Would ignition issues show up on diagnostics?

    Cheers,
    Bill

  2. #2
    E500E Guru Melville's Avatar
    Join Date
    Oct 2012
    Location
    Washington DC
    Posts
    862

    Re: M119 low on power - suggestions?

    Clogged catalytic converters?

  3. The Following User Says Thank You to Melville For This Useful Post:

    TerryA (09-15-2018)

  4. #3
    Senior Member LWB250's Avatar
    Join Date
    Feb 2018
    Location
    Tampa, FL
    Posts
    299

    Re: M119 low on power - suggestions?

    I would definitely look at ignition. Typical failure mode for the EZL will disable four of the eight cylinders. The car will (amazingly) still run and do so quite smoothly, as failure is evenly distributed between cylinder banks, but the car will be seriously lacking in power.

    Don't ask me how I know this....

    Dan

  5. The Following User Says Thank You to LWB250 For This Useful Post:

    TerryA (09-15-2018)

  6. #4
    .036 Hoonigan™
    E500E Boffin
    gsxr's Avatar
    Join Date
    Dec 2008
    Location
    Boise, ID, USA
    Posts
    21,518

    Re: M119 low on power - suggestions?

    Ignition issues almost never appear on diagnostics (unless it's a major failure), so if it's running smoothly on all 8 cylinders, ignition isn't your problem. If 4 cylinders are not firing, the idle will be extremely rough. Chain stretch is nice to check at some point but also won't cause a large power loss. Plugged cats will cause a high-RPM power loss.

    Is it low on power everywhere in the RPM band? How about part throttle vs full throttle? If the cam advance mechanisms aren't enaging, that will cause weak power in the midrange (2k-4k).


  7. The Following 2 Users Say Thank You to gsxr For This Useful Post:

    maw1124 (09-14-2018), TerryA (09-15-2018)

  8. #5
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    It's decatted so that counts out cat issues. Drives ok normally but give it full throttle and I don't feel all the power coming. Doesn't pull as hard as you would expect a 500 to. No idle issues, smooth as anything.

    Cam advance mechanisms throw a code? How can I diagnose those?

  9. The Following User Says Thank You to e500.org For This Useful Post:

    TerryA (09-15-2018)

  10. #6
    .036 Hoonigan™
    E500E Boffin
    gsxr's Avatar
    Join Date
    Dec 2008
    Location
    Boise, ID, USA
    Posts
    21,518

    Re: M119 low on power - suggestions?

    If power feels normal from 4500rpm to redline, it's worth ch ecking the cam advance mechs. There is an actuation test available via SDS / HHT-Win, when the solenoid is active at idle, the idle should get rough and drop in RPM (the test walks you through this). This would only cause a loss in midrange power though. Wouldn't hurt to also check MAF readings for grins.


  11. The Following User Says Thank You to gsxr For This Useful Post:

    TerryA (09-15-2018)

  12. #7
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    Thanks Dave! It's a replacement MAF but of course could still be faulty as it was used. I'll try and get the readings and post here.

  13. The Following User Says Thank You to e500.org For This Useful Post:

    TerryA (09-15-2018)

  14. #8
    Site Honcho
    Klugscheisser
    Ich bekenne mich
    nicht schuldig.
    gerryvz's Avatar
    Join Date
    Nov 2008
    Location
    Annapolis, MD
    Posts
    17,822

    Re: M119 low on power - suggestions?

    Quote Originally Posted by LWB250 View Post
    I would definitely look at ignition. Typical failure mode for the EZL will disable four of the eight cylinders. The car will (amazingly) still run and do so quite smoothly, as failure is evenly distributed between cylinder banks, but the car will be seriously lacking in power.

    Don't ask me how I know this....

    Dan
    My direct experience with M119 EZL failure was the exact opposite. One entire bank (four contiguous cylinders, being Nos. 1-4) of the engine went dead.

    Yes, the engine still operated, but it ran extremely roughly and sounded like a Subaru flat-four engine. I had to drive it for a bit and was sweating bullets about poisoning the cats with unburnt gasoline.

    One other obvious way to tell (and I've seen this both with failed M119 EZL and a failed coil pack covering two cylinders on the M104) is that you get a very strong smell of unburnt gasoline out the exhaust pipe.

    From everything I know and have seen, the EZL failure is either the entire thing (all eight cylinders) or one bank of four attached cylinders is taken out. But not an even distribution of non-firing cylinders.

    Cheers,
    Gerry

  15. The Following User Says Thank You to gerryvz For This Useful Post:

    TerryA (09-15-2018)

  16. #9
    "Nit-Picky and
    Bitter Mechanic"
    jhodg5ck's Avatar
    Join Date
    Jul 2009
    Location
    Lilburn, GA
    Posts
    2,234

    Re: M119 low on power - suggestions?

    what do your plugs look like? Obviously lean or rich?

    Even with the actuators pinned in place the cars dont feel terribly weak...and for both to fail simultaneously seems a might bit unlikely.

    I'm thinking more of a mixture issue. A wideband stand alone O2 sensor and gauge is always a handy diagnostic tool.

    Compression issues Typically manifest themselves in smoke...be it @ idle/accelerating/starting in the morning etc, etc, etc...

    jono
    Blue Ridge Mercedes Jonathan Hodgman
    Mercedes Repair Atlanta
    http://www.blueridgemb.com/
    08 E63 05 E55 Estate 95 S600 94 SL700 93 500E Brumos/RTech 92 500E T/R 93 500E (122)
    91 560SEC ECE 87 Hammer Coupe, Sedan and Wagon 6.0L 32V 86 560SEL AMG 6.0L 32V

  17. The Following 3 Users Say Thank You to jhodg5ck For This Useful Post:

    gsxr (09-15-2018), maw1124 (09-14-2018), TerryA (09-15-2018)

  18. #10
    E500E Guru maw1124's Avatar
    Join Date
    May 2011
    Location
    FL & MI, USA
    Age
    46
    Posts
    1,548

    Re: M119 low on power - suggestions?

    Since caps and rotors have been done, I second Jono’s suggestion of plugs. And I’ll add fuel pumps. Are they original? My S55 ran fine on light throttle, but as soon as I went 1/4 throttle into it, she sputtered and what not, running lean. No CEL, but no power either. So if the plugs have been changed within the last few years but the fuel pump is original, I’d look there too. You say she’s idling smoothly, so I think that rules out computers and compression. I’d go at it with a fuel pressure gage first, and if she’s starting and running fine on low fuel, that has the silver lining of telling you everything else is probably fine (computers, MAF, compression, plugs, etc.)

    GL

    maw
    Last edited by maw1124; 09-14-2018 at 05:36 PM.

  19. The Following User Says Thank You to maw1124 For This Useful Post:

    TerryA (09-15-2018)

  20. #11
    Senior Member LWB250's Avatar
    Join Date
    Feb 2018
    Location
    Tampa, FL
    Posts
    299

    Re: M119 low on power - suggestions?

    Quote Originally Posted by gerryvz View Post
    My direct experience with M119 EZL failure was the exact opposite. One entire bank (four contiguous cylinders, being Nos. 1-4) of the engine went dead.

    Yes, the engine still operated, but it ran extremely roughly and sounded like a Subaru flat-four engine. I had to drive it for a bit and was sweating bullets about poisoning the cats with unburnt gasoline.

    One other obvious way to tell (and I've seen this both with failed M119 EZL and a failed coil pack covering two cylinders on the M104) is that you get a very strong smell of unburnt gasoline out the exhaust pipe.

    From everything I know and have seen, the EZL failure is either the entire thing (all eight cylinders) or one bank of four attached cylinders is taken out. But not an even distribution of non-firing cylinders.

    Cheers,
    Gerry
    My 1995 W140 S500 coupe failed an EZL and that's exactly what it was doing. I don't recall the idle quality, but I know it ran decently at speed but was completely gutless. And you didn't want to light a match or have open flame around the exhaust for sure...

    Dan

  21. #12
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    Thanks all for the suggestions. I was out in the car last night and basically if I'm going 60kmh and I give it full throttle it doesn't go like a 500 should, it's very lazy and climbs up the rev range slowly. I'll get a video up if that helps?

    I think I need a new Voltage Regulator or Alternator too. I had battery issues, replaced the battery with the one out of my E55 then ran it. Day 2 evening after driving the car all day, switch off and try and restart and it's dead. I suspect battery drained and alternator not charging it. After reading on this forum last night and speaking with Joe (JC220) we think the VR is faulty and needs changing in the first instance. I will check the voltage at fast idle today and report back.

    So need to sort that first then consider the above. Certainly value in changing the spark plugs, fuel pumps and also the ignition coils (not replaced in last 10yrs) and o2 sensor (again not replaced in st last 10 yrs).

    No blue or otherwise smoke from the exhaust. Exhaust does smell like fuel but i thought that would be down to the decat?

  22. The Following User Says Thank You to e500.org For This Useful Post:

    TerryA (09-15-2018)

  23. #13
    Site Honcho
    Klugscheisser
    Ich bekenne mich
    nicht schuldig.
    gerryvz's Avatar
    Join Date
    Nov 2008
    Location
    Annapolis, MD
    Posts
    17,822

    Re: M119 low on power - suggestions?

    I think your issue is bad coils.

  24. The Following User Says Thank You to gerryvz For This Useful Post:

    TerryA (09-15-2018)

  25. #14
    Member
    Join Date
    May 2014
    Location
    Finland
    Posts
    82

    Re: M119 low on power - suggestions?

    Hi,

    Absolutely the best way the debug this kind of issues is to put the car on dynamometer and connect the exhaust gas analyzation and ignition oscilloscope. And the most important, have the mechanic who knows how the engine should behave. With these tools you’ll get several measurements of the ignition and combustion over the whole area of operation (from min to max rpm with different load). As a bonus you’ll get performance curves.

    Years ago I had annoying power loss situation with my W123/M110. Finally I took the car to a professional mechanics who tuned racing cars for living. He used these methods to investigate the car and finding out the slight misbalance between injection sprays.

  26. The Following 2 Users Say Thank You to Efraim For This Useful Post:

    gsxr (09-15-2018), TerryA (09-16-2018)

  27. #15
    postwhore posterchild Klink's Avatar
    Join Date
    Feb 2014
    Location
    Abstract Plains, USA
    Posts
    4,062

    Re: M119 low on power - suggestions?

    To avoid confusion as you are attempting to diagnose these things, it is important to note the following with these twin coil/twin distributor ignition systems on 119 motors:
    Each distributor/coil combination DOES NOT fire “a bank“ of cylinders, as in one through four, or five through eight. These are “true“ V-8 engines. They are not “two four-cylinder engines on a common crank” as with a so-called “flat crank“ V8.
    Each distributor fires two cylinders on each bank. That’s why there are four spark plug wires that run across the motor,
    two from the left distributor to the right bank, and two from the right distributor to the left bank, and not simply four wires from the distributor straight back to the cylinders of a bank that a distributor is on...
    Putting the fun in dysfunction...

  28. The Following 6 Users Say Thank You to Klink For This Useful Post:

    Bogeyman (09-15-2018), Eno (09-16-2018), gsxr (09-15-2018), JC220 (09-15-2018), maw1124 (09-17-2018), TerryA (09-16-2018)

  29. #16
    .036 Hoonigan™
    E500E Boffin
    gsxr's Avatar
    Join Date
    Dec 2008
    Location
    Boise, ID, USA
    Posts
    21,518

    Re: M119 low on power - suggestions?

    I would not expect weak/failing ignition coils to provide smooth operation with low power... but rather an intermittent misfire.

    Plugs wouldn't do it either, I believe Jono meant to read the plugs and see if they are badly fouled (rich mixture) or bright white (lean mixture) instead of the normal light tan color. This will let you know if the mixture is way off.

    Fuel pumps is another good idea though. Lower-than-normal fuel pressure will cause a power reduction (severe at times, if pressure is low enough) with smooth running and no misfire. This is difficult to diagnose, as it could possibly be a fuel feed issue from the tank as well, in which case new pumps wouldn't cure it. Only way to pinpoint this is temporarily connecting a fuel pressure gauge that can be viewed from the driver seat while driving, to see if pressure is normal when the power loss occurs. See post #83 here for the components I used when diagnosing my E420... in my case, the power loss was intermittent, and severe, after ~10 mins of driving. Pressure would drop to ~25psi or so.



  30. The Following 2 Users Say Thank You to gsxr For This Useful Post:

    maw1124 (09-17-2018), TerryA (09-16-2018)

  31. #17
    "Nit-Picky and
    Bitter Mechanic"
    jhodg5ck's Avatar
    Join Date
    Jul 2009
    Location
    Lilburn, GA
    Posts
    2,234

    Re: M119 low on power - suggestions?

    Quote Originally Posted by gsxr View Post
    I would not expect weak/failing ignition coils to provide smooth operation with low power... but rather an intermittent misfire.

    Plugs wouldn't do it either, I believe Jono meant to read the plugs and see if they are badly fouled (rich mixture) or bright white (lean mixture) instead of the normal light tan color. This will let you know if the mixture is way off.

    Fuel pumps is another good idea though. Lower-than-normal fuel pressure will cause a power reduction (severe at times, if pressure is low enough) with smooth running and no misfire. This is difficult to diagnose, as it could possibly be a fuel feed issue from the tank as well, in which case new pumps wouldn't cure it. Only way to pinpoint this is temporarily connecting a fuel pressure gauge that can be viewed from the driver seat while driving, to see if pressure is normal when the power loss occurs. See post #83 here for the components I used when diagnosing my E420... in my case, the power loss was intermittent, and severe, after ~10 mins of driving. Pressure would drop to ~25psi or so.


    Yup....reading plugs for signs of lean/rich.

    Sent from my SM-G960U using Tapatalk
    Blue Ridge Mercedes Jonathan Hodgman
    Mercedes Repair Atlanta
    http://www.blueridgemb.com/
    08 E63 05 E55 Estate 95 S600 94 SL700 93 500E Brumos/RTech 92 500E T/R 93 500E (122)
    91 560SEC ECE 87 Hammer Coupe, Sedan and Wagon 6.0L 32V 86 560SEL AMG 6.0L 32V

  32. The Following 2 Users Say Thank You to jhodg5ck For This Useful Post:

    e500.org (09-15-2018), gsxr (09-15-2018)

  33. #18
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    Here is a picture of one of the plugs a few months ago. Looks very dry / white.

    Thanks again all for inputs so far.
    Attached Images Attached Images

  34. #19
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    Another
    Attached Images Attached Images

  35. #20
    "Nit-Picky and
    Bitter Mechanic"
    jhodg5ck's Avatar
    Join Date
    Jul 2009
    Location
    Lilburn, GA
    Posts
    2,234

    Re: M119 low on power - suggestions?

    way to much flash and I can't get a good read/look at the ceramic.. does appear to be some contaminate on the electrode though...not much wear so I'm guessing they don't have a lot of miles on them

    that said, if they are STARK white then yes, they are burning Lean... At the very least I think it's safe to say she's not running overly rich!
    Blue Ridge Mercedes Jonathan Hodgman
    Mercedes Repair Atlanta
    http://www.blueridgemb.com/
    08 E63 05 E55 Estate 95 S600 94 SL700 93 500E Brumos/RTech 92 500E T/R 93 500E (122)
    91 560SEC ECE 87 Hammer Coupe, Sedan and Wagon 6.0L 32V 86 560SEL AMG 6.0L 32V

  36. The Following User Says Thank You to jhodg5ck For This Useful Post:

    maw1124 (09-17-2018)

  37. #21
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    Yeah sorry about that. Screenshots from a video I took a few months ago. I'll get some proper pictures this week. Thanks for the input - and yes you are right plugs don't have many miles at all.

  38. The Following User Says Thank You to e500.org For This Useful Post:

    TerryA (09-16-2018)

  39. #22
    .036 Hoonigan™
    E500E Boffin
    gsxr's Avatar
    Join Date
    Dec 2008
    Location
    Boise, ID, USA
    Posts
    21,518

    Re: M119 low on power - suggestions?

    Sample photos attached of "normal" used plugs, with a new one on the far right for comparison.

    Attached Images Attached Images

  40. The Following 2 Users Say Thank You to gsxr For This Useful Post:

    emerydc8 (09-15-2018), TerryA (09-16-2018)

  41. #23
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    Quote Originally Posted by gsxr View Post
    Sample photos attached of "normal" used plugs, with a new one on the far right for comparison.

    Thanks Dave. My plugs are certainly white at the tip - I would say they have 5-6kkm on them. I will remove them this evening from both banks and post back.

    With regards to the charging issue, I recharged the battery from my E55 and put it in the 500E. At idle the battery voltage reads 14.2V. This seems to tell me that the alternator is working. I will try give it throttle action and see if the voltage fluctuates - if it does I think that means the Voltage Regulator is faulty.

    BTW alternator was new around 12-18 months ago but again not too many miles put on it.

  42. The Following User Says Thank You to e500.org For This Useful Post:

    TerryA (09-16-2018)

  43. #24
    E500E Guru e500.org's Avatar
    Join Date
    Nov 2012
    Location
    Dubai, United Arab Emirates
    Posts
    515

    Re: M119 low on power - suggestions?

    All - what is the purpose of the knock sensor? The wiring for this seems to be slightly degraded and I have a knock sensor with the car. It seems like a big job as the wiring goes under the engine mounts. Been quoted 200 GBP to replace it.

    Before I do that - would the knock sensor throw a code on STAR?

  44. The Following User Says Thank You to e500.org For This Useful Post:

    TerryA (09-16-2018)

  45. #25
    .036 Hoonigan™
    E500E Boffin
    gsxr's Avatar
    Join Date
    Dec 2008
    Location
    Boise, ID, USA
    Posts
    21,518

    Re: M119 low on power - suggestions?

    A faulty knock sensor would normally trigger a code, probably on the EZL / DI. The purpose is what it sounds like, to sense knock/detonation, and pull ignition timing. If it was causing the EZL to pull a bunch of timing, yes, that would cause a low power scenario. Replacing the sensor is a miserable job as the motor mounts AND brackets must be removed. £200 sounds downright reasonable.


  46. The Following 2 Users Say Thank You to gsxr For This Useful Post:

    e500.org (09-16-2018), maw1124 (09-17-2018)

Similar Threads

  1. VMI Request, any suggestions?
    By J-Sauce in forum Off-Topic Discussions
    Replies: 14
    Last Post: 04-05-2017, 06:14 AM
  2. Wheel suggestions for 124.051
    By JoeB in forum Wheels and Tires
    Replies: 0
    Last Post: 09-14-2016, 06:31 PM
  3. Suggestions on getting a PPI in Boston
    By cmaghami in forum Eastern/Northeastern US
    Replies: 0
    Last Post: 07-25-2016, 11:35 AM
  4. Wheel Suggestions
    By supernova in forum Wheels and Tires
    Replies: 5
    Last Post: 09-24-2012, 01:19 PM
  5. E420 M119 Power/Torque Diagramm
    By Christian_K in forum 400E / E420 Discussions
    Replies: 0
    Last Post: 06-23-2011, 09:30 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •