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Thread: @Xulfiqar Sb: Bought c180 98 model (my 1st Merc) Help with startup maintenance/repair

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    Default @Xulfiqar Sb: Bought c180 98 model. Need help with maintenance/repair.

    @Xulfiqar Sb:
    I have seen lots of threads and lots of posts and am deeply impressed by your knowledge of vehicles. I am trying to browse through but things are so spread about that it is confusion. Moreover, perhaps every case is different and need specialized help, at least for the first time.

    This Monday, I bought a c180 98, Elegance Model with 93K miles (allegedly) on the odo. In driving for these 3 days I have jotted up a list of my observations, some serious, I believe. I need your expert advice on it. Here is the list of serious observations:

    [Post Edited with problems listed as solved/unsolved. The details of how a problem was solved is spread all over the many pages and posts. Please delve into the thread for details.]

    SOLVED PROBLEMS WITH CAUSES AND REMEDIES:
    ---------------------------------------------------------------------------
    1. Vibration in D, Cause: One engine mount was cut, replaced.
    2. Temp gauge does not get to half point, Cause: T-stat valve was jammed, replaced.
    3. Fluids replaced = Engine Oil and Transmission oil.
    4. Vibration in steering at all speeds, Causes: Mountings (changed), warped rotors, machined, balancing and alignment done. New steering shock installed.
    5. Rear Left Window does not close with button on door, Cause: Button faulty, replaced.
    6. Random HVAC blower speed: Ordered HVAC control unit from eBay. Fitted and working fine. No more issue.
    7. Broken Cruise Control: Ordered from eBay. Fitted and working fine.
    8. SRS AIRBAG Warning Light in Dash, Cause: Star scan tool (at Papu ustad, Pindi) told about two crash sensors (one under each front seat) to be faulty (or their connection is faulty). Shop gave a price of Rs.7,000 for 2 but I see that used are cheaply available on eBay. Would order two soon.
    9. Left handbrake shoe friction sound. I fitted new handbrake shoes and thought it needed adjustment. However, it turned out, after 5 tries at it, that the lug nuts on the wheels were of slightly varying length. The longer ones would brush on the handbrake clip that expands the mechanism. Older one was damaged. Got it replaced. Sound started coming after few days. I swapped some lug nuts from other wheels. It is peace ever since!
    10. Intermittent Windows -- Passenger and Driver side windows would not operate after few days of reset in any order. I suspected the rear-left window control module, opened the door cover to find that there is no window control module there! So this must not be the cause.
    Recently, I cleaned all the electric ground points in the vehicle. The issue of intermittent windows had reduced a great deal. More so, because before starting the vehicle, I operate all windows (first point in ignition).
    11. COOLANT VANISHING -- I needed to add 1 L in like 2 weeks (driving 300 miles). The cause was a leaky radiator. In summers the problem increased until I saw coolant drops beneath an idling car. Previous radiator was corroded with use of wrong coolant. Radiator replaced with a good condition exact part (Behr) from a half-cut. Coolant used would definitely be as per spec or MB.

    UNSOLVED PROBLEMS that are being debugged:
    ------------------------------------------------------------
    12. Relay clicking type sound behind key:
    The sound can start anytime but luckily not too often. Usually in peaceful driving it would be calm. Sometimes when I take some action like press brake pedal, turn on indicator, it will start clicking. I can feel the throbbing when I touch the key. Would start and stop itself.
    I have found out that whenever that clicking sound is heard, horn won't blow. Conversely when the horn does not blow, there are chances of those clicking sounds. When the horn blows, there won't be any clicking sound in that drive. Still trying to solicit the cause in a deterministic way.
    13. Sudden Downshift Jerk: Sometimes after driving the vehicle for a long time, like one hour, when slowing down because of mild braking (to a speed for which 1st gear may be needed) the car shifts into 1st gear very hardly.
    Kindly please advise. I am a keeper since I am a busy person. The car I was driving before this is with me for 9 years. For once, I want this car to be in a state that I know how things are. Thank you in anticipation and sorry for trouble.

    @Xulfiqar Sb Bought c180 98 model my 1st Merc Help wi startup maintenancerepair -1636367

    PS: Car is with me for 6 months now, with 99,000 miles on Odo. (21 May, 2016)
    Aamer

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    Quote Originally Posted by Marschall View Post
    Sir i dont have his no. but yes Noman is good But Mr Behram is too shrewd.Did you get the window sorted out??? You can also try my Mechanic he is very good and listens to you unlike Papu ustaad and his crew
    Thank you.
    Please give information about your mechanic -- contact no and location.
    Window issue: I think I have solicited the problem but since it is not an issue that troubles the drive of the car, I am not very concerned about it.
    More important right now is, horn (today the car infront rolled back and hit me and I could just sit and watch! ), coolant vanishing and the sound of clicking from probably EIS!
    This reminds me, you were to buy some EIS and key etc. How did that project go and if successful what are the costs?

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    03215054125 Majid near kamran market saddar.He is better compared to Papu.That EIS project is on hold as the uk freq keys are different from Jap model FOBs
    "Stand by your glasses steady and drink to your comrade's eyes.
    Here's a toast to the dead already and hurrah for the next to die."

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    Did u install new sparkplugs?? if yes kindly tell me which brand? Bosh or Hella?
    "Stand by your glasses steady and drink to your comrade's eyes.
    Here's a toast to the dead already and hurrah for the next to die."

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    What's the expenses tally, parts + labour so far?
    Be polite on the road. Always give way to others, particularly ambulances and pedestrians.

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    Quote Originally Posted by Marschall View Post
    Did u install new sparkplugs?? if yes kindly tell me which brand? Bosh or Hella?
    The spark plugs the car got, during the first mechanic visit after I bought the car -- a time when I was not much into knowing things myself, were OWS spark plugs with 1.0 mm electrode gap.
    I read somewhere, probably on OWS website that this particular model requires a gap of 0.8 mm so I re-gaped them.
    However, seeing how the car behaves (responsiveness and mileage), my guess is these plugs are not appropriate. So I will soon be going with BOSCH or NGK. When I got the car, the plugs were 3 tip BOSCH (platinum I guess). Pretty used.
    I am hoping some good quality spark plugs (as close to factory specs as possible) will improve the car's mileage figures of around 9.2 km/L for within city drive.

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    Quote Originally Posted by autophile View Post
    What's the expenses tally, parts + labour so far?
    I got the car for 10.25 lac. Since Nov 2015, I have parts, lubes, tyres worth Rs.2.1 lac and labour Rs. 0.35 lac.
    That is not much considering that whatever I have changed is probably being changed when those parts were due to be changed due to age (18 years) or are maintenance items.
    The car is a daily driver, and Alhamdulillah, till now, I am satisfied at how she is handling.
    As stated previously, for once at least, I need to get the car to a state where I can say, there are no 'known' issues!
    I hope I will be there soon, InShaAllah.

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    Quote Originally Posted by x2 View Post
    I got the car for 10.25 lac. Since Nov 2015, I have parts, lubes, tyres worth Rs.2.1 lac and labour Rs. 0.35 lac.
    That is not much considering that whatever I have changed is probably being changed when those parts were due to be changed due to age (18 years) or are maintenance items.
    The car is a daily driver, and Alhamdulillah, till now, I am satisfied at how she is handling.
    As stated previously, for once at least, I need to get the car to a state where I can say, there are no 'known' issues!
    I hope I will be there soon, InShaAllah.
    That's great. You have put in a lot in this car and it's good that you are enjoying it.
    Be polite on the road. Always give way to others, particularly ambulances and pedestrians.

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    Quote Originally Posted by Marschall View Post
    03215054125 Majid near kamran market saddar.He is better compared to Papu.That EIS project is on hold as the uk freq keys are different from Jap model FOBs
    Thank you. Based on what is the work I need to get done, I will decide whom to visit. Despite the hearsay that Papu Ustad is expensive, he charged very nominal from me.
    Nonetheless it is good to have a second opinion and multiple options at hand. You never know when someone stops being helpful and start extorting money!
    For example, Papu ustad's son, diagnosed that the radiator in my car is leaking (although it was the AC person who threw a bucket of water on the AC radiator that he saw actually) and tried to sell me a used radiator for Rs.18,000! I, however, said I will make up my mind and then see. As mentioned in a previous post, new Bremen radiator is being sold for Rs.18,300 (prices taken from Indus Autos a few days ago).
    The two crash sensors (used) were quoted for Rs.7,000 as special price to me, but I am able to find an Euro 1 per sensor price on eBay! Though I am not buying that but I can get two for less than 10 pounds!
    So my guess is, these cars must only be own by people who know about cars or have so much money that they do not need to know anything! Unless you do not know what is the problem, you will most probably be looted on the spot by instilling fear/panic (just like doctors do) into the user to act quickly.

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    @Xulfiqar:
    Is this black thing the 'clock spring' behind the steering wheel? Image in next post.
    What is the part number for this model?
    Any website where I can find correct part numbers?

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    Clock Spring?

    @Xulfiqar Sb Bought c180 98 model my 1st Merc Help with startup maintenancerepair -1669513

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    Well, well, well!

    Yesterday, I thought to do a Power-Reset of the car since I felt quite a few things were not working in the car and rather than blaming the specific circuits, to be sure it is not part of the 'Electric Ghost' problem.

    Remember, I had removed fuse number 17 (rear passenger side window) in an attempt to catch the controller causing CAN Bus troubles. It is probably over a month now, since I had removed it. Both front windows would intermittently go bad before doing that, within a few days after Power-Reset. This time, the windows are working till now. However, down the line, the following things went bad:

    1. Front interior light operation with opening of door (light glows at the press of button but not when opening door). Only rear interior light will glow when door is opened.
    2. The RF receiver of the car. So to lock-unlock the car, I had to point the key towards door handle, to use the IR signaling, I believe. It won't work from within the pocket.
    3. Horn - after showing some intermittent behaviour, the horn finally completely died, as mentioned in previous posts.

    And guess what! After the reset, all these three things are working again.

    So for now, I guess, my only next to-do is what Xulfiqar has been suggesting all along, i.e.,
    1. to check and clean all the grounding points of the vehicle, and
    2. check the X30 connector and clean its connections.

    And if this does not resolve the problem, and given that there are random infrequent repeated clicking problem from behind the key (probably EIS), can the real culprit be EIS -- since it is the gateway of the CAN Bus! Can it do, all these things?

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    ... and today the passenger side window is not working!
    This brings me back to square one! So allegedly, rear passenger side window controller is not probably the 'only' problem controller!

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    @Xulfiqar:
    I teach at the EE dept of a local university. We give undergraduate final year projects providing engineering solutions to common problems. Can we develop our own OBD-II scanner to read all kind of diagnosis? I wish to know,

    i) If the OBD-II protocol details are public or not? If public, can you help me lay hands on them. If not, how to access them.

    ii) My idea is, rather than reading a fault code off-line, why not develop a cheap solution to generate a message right when the fault code is generated. Moreover, to provide a snap shot of how the car is performing in real-time. I am sure, there will be lots of such tools already available but students learn a lot even when re-doing existing things.

    iii) What additional functionality would be too good to have. Especially if it is not already available.

    iv) What would be the challenges faced when doing this?

    One strategy is, to buy a scanner and develop a T-joint that reads all the communication to understand how the OBD-II scanners operate, i.e., if the protocol is not publicly available.

    I would your comments on this.

    Others are welcome to comment sensibly too.

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    Quote Originally Posted by x2 View Post
    @Xulfiqar:
    I teach at the EE dept of a local university. We give undergraduate final year projects providing engineering solutions to common problems. Can we develop our own OBD-II scanner to read all kind of diagnosis? I wish to know,

    i) If the OBD-II protocol details are public or not? If public, can you help me lay hands on them. If not, how to access them.

    ii) My idea is, rather than reading a fault code off-line, why not develop a cheap solution to generate a message right when the fault code is generated. Moreover, to provide a snap shot of how the car is performing in real-time. I am sure, there will be lots of such tools already available but students learn a lot even when re-doing existing things.

    iii) What additional functionality would be too good to have. Especially if it is not already available.

    iv) What would be the challenges faced when doing this?

    One strategy is, to buy a scanner and develop a T-joint that reads all the communication to understand how the OBD-II scanners operate, i.e., if the protocol is not publicly available.

    I would your comments on this.

    Others are welcome to comment sensibly too.
    Why build something that is already available in retail? I would suggest that students get a more deeper understanding of the "hows" and "whys" of such systems - it makes it easier to understand the build logic.

    OBDII has generalized almost all powertrain error codes which are recorded as Pxxxx type codes, deeper level like body, security etc is still a bit hit or miss - e.g. BMW are not like benz in this regard. They do have their B and A type codes but require a different interrogation.



    I also read you want to see the error code as it happens, this provision is already provided and is called "freeze frame data" - this data basically takes a snapshot of all the events that happened to the ECU at the time of the code, e.g. it will tell you, engine rpm, vehicle speed, coolant sensor value, air temperature sensor value, Air mass value, manifold vacuum value, throttle position, system voltage - more fancier cars will tell you gear position, body control values and also more stuff like applied throttle, fuel delivery etc..

    This really helps in diagnosis as you can sort of make a picture of the condition of the event that caused your error.
    ZRS - Zulfiqar Racing Systems ..... - professionals at work - at crackwheels.com

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    Quote Originally Posted by Xulfiqar View Post
    Why build something that is already available in retail? I would suggest that students get a more deeper understanding of the "hows" and "whys" of such systems - it makes it easier to understand the build logic.

    OBDII has generalized almost all powertrain error codes which are recorded as Pxxxx type codes, deeper level like body, security etc is still a bit hit or miss - e.g. BMW are not like benz in this regard. They do have their B and A type codes but require a different interrogation.



    I also read you want to see the error code as it happens, this provision is already provided and is called "freeze frame data" - this data basically takes a snapshot of all the events that happened to the ECU at the time of the code, e.g. it will tell you, engine rpm, vehicle speed, coolant sensor value, air temperature sensor value, Air mass value, manifold vacuum value, throttle position, system voltage - more fancier cars will tell you gear position, body control values and also more stuff like applied throttle, fuel delivery etc..

    This really helps in diagnosis as you can sort of make a picture of the condition of the event that caused your error.
    Xylfiqar sent y a private mesage. Pls read
    Loaded with SQ setup

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    Quote Originally Posted by Xulfiqar View Post
    Why build something that is already available in retail? I would suggest that students get a more deeper understanding of the "hows" and "whys" of such systems - it makes it easier to understand the build logic.

    OBDII has generalized almost all powertrain error codes which are recorded as Pxxxx type codes, deeper level like body, security etc is still a bit hit or miss - e.g. BMW are not like benz in this regard. They do have their B and A type codes but require a different interrogation.

    I also read you want to see the error code as it happens, this provision is already provided and is called "freeze frame data" - this data basically takes a snapshot of all the events that happened to the ECU at the time of the code, e.g. it will tell you, engine rpm, vehicle speed, coolant sensor value, air temperature sensor value, Air mass value, manifold vacuum value, throttle position, system voltage - more fancier cars will tell you gear position, body control values and also more stuff like applied throttle, fuel delivery etc..

    This really helps in diagnosis as you can sort of make a picture of the condition of the event that caused your error.
    Thank you for your reply.

    1. As to why would we want students to make something already available is this helps them get the confidence to do something. Undergraduate students, generally, are not meant to invent! Once they get their hands on experience working on things like understanding protocols and building modules to given specs, they break the ice to 'building' and 'making'. Later they can expand their expertise and can do something worthwhile.

    2. Reading the error code as it happens, as you say, will make the diagnosis easier. So problems like with my car might become easier to debug. So if we can have time stamped data along with all events, we can, sort of , replay and see what might have went wrong. I am hoping that through this project, I am able to diagnose problem with my car too!

    3. Is there something specific that can be and should be done as an undergraduate Final year project? We can work on multiple ideas with multiple groups.

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    I would suggest you get your students to understand how the control unit is recieving data and what are the "normal" and "abnormal" parameters for this.

    I have found that a good labscope can help in understanding the "how and what" of whats going on. It can also give you a looking glass view of a failure point (e.g. heated up solenoid coil going fuzzy)
    ZRS - Zulfiqar Racing Systems ..... - professionals at work - at crackwheels.com

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    Update on car:
    Got new front disc pads fitted. Pads are TEXTAR for Rs.4500 (one sensor included, additional sensor for Rs.200). The previous were noisy and these in comparison are way too quite. This has improved the ride quality. Got them from Waheed Autos.

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    @Xulfiqar - Re: hard 2 to 1 downshift.

    I thought this issue got resolved but I just found that this hard down shift comes into action after driving the car for like 1 hour and 15 minutes or more. It does not happen for a drive of less than 1 hour, whence things remain smooth and fine.

    My commute reduced to less than an hour so I did not notice it for quite a while until a friend came from abroad and I had to take him around in the city for some visits. After driving around for like 2 hours, the hard 2 - 1 downshift recurred.

    I wonder what causes this strange behaviour!

    My personal (layman) idea is that this has to do with the transmission-system 'heating up' beyond a certain temperature (what else can 'time' effect) triggering something to malfunction causing this erratic behaviour.

    Some of my searches on the Internet suggests that the issue may be with conductor plate (and speed sensing). The poster suggested that he got that changed and everything resolved.
    Transmission vibration - Mercedes-Benz Forum

    I guess, I need to check the transmission oil level. Then to check the transmission fluid cooling system (how to do that). What else?
    Would diagnostics help?

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    Quote Originally Posted by x2 View Post
    @Xulfiqar - Re: hard 2 to 1 downshift.

    I thought this issue got resolved but I just found that this hard down shift comes into action after driving the car for like 1 hour and 15 minutes or more. It does not happen for a drive of less than 1 hour, whence things remain smooth and fine.

    My commute reduced to less than an hour so I did not notice it for quite a while until a friend came from abroad and I had to take him around in the city for some visits. After driving around for like 2 hours, the hard 2 - 1 downshift recurred.

    I wonder what causes this strange behaviour!

    My personal (layman) idea is that this has to do with the transmission-system 'heating up' beyond a certain temperature (what else can 'time' effect) triggering something to malfunction causing this erratic behaviour.

    Some of my searches on the Internet suggests that the issue may be with conductor plate (and speed sensing). The poster suggested that he got that changed and everything resolved.
    Transmission vibration - Mercedes-Benz Forum

    I guess, I need to check the transmission oil level. Then to check the transmission fluid cooling system (how to do that). What else?
    Would diagnostics help?
    the 2-1 nudge you feel on downshift is not a "harsh bump" - to remedy it (as in lessen it) - you will need to remove the valve body and inspect the line pressure regulator valve - in old models of this gearbox (like you have) the pressure regulator spring breaks and will cause funny shifts. In almost all high mileage 722.6 gearbox the overlap valve sleeves will wear and be loose (lose pressure) as the valve body is very soft. - There are some replacement parts for this but all are aftermarket and are only sold in USA. (genuine mercedes benz parts will be loose and to remedy that MB says to buy a brand new cast valve body).

    leaking overlap pressure will cause a slight nudge when downshifting and about 100 rpm flutter on gearshifts (quite hard to detect for average user)

    In any case a warmed up gearbox runs far smoother than a cold one, a used high miles cold 722.6 gearbox will lurch shift and bump 2-1 and also 1-2 shift - It may even drag 1st gear when shifting from P to D. This is due to the torque converter clutch being applied (MB have a unique way to apply and deapply the clutch - they dont employ disengagement springs on it like every other manufacturer. a US company makes a torque converter where they have put in very light springs to take care of the cold drag (it gets really bad in frozen weather if you are using a cheaper ATF).

    The conductor plate is basically a fancy wiring loom - it has two speed sensors built into it - input/output - if they would malfunction your TCU will spare no time in shutting down the gearbox shifting program - those two sensors are what the TCU uses to identify what ratio the gearbox has and time the target gear shifts.
    ZRS - Zulfiqar Racing Systems ..... - professionals at work - at crackwheels.com

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