artsym

Hi all,

My CLK320 (W209/2002/Petrol/Coupe) story:

1. Suddenlycar lost all of the acceleration on the motorway.
2. After a few seconds all lights came on on the dashboard with checkengine, battery etc.
3. The car cutoff.
4. When I tried to start it again it has been starting but switching off straight away. No error codes and no check engine...
5. Once battery got worse the car stopped starting at all.
6. Theman from recovery said his diagnostics tool showed him that the problems are comming from the crank sensor
7. I have replaced crancshaft sensor myself at home (it was very hard to reach...) and recharged battery. The car started for 2 seconds and cutoff as before. Then wouldnt start again (my battery charger is not the best.)
8. As a result - crankshaft sensor replacement made no difference.
9. I have iCarsoft MB2 diagnostics tool.
   1. There are no ODB2 errors.
   2. There is an error in other system when I do diagnostics but i don't think this is related to the issue (for example "low voltage to circuit 87" p2600)

Please help and advice what could be causing car not starting?
Or how could i determine what is the issue using my diagnostics tool//Multimetr etc?
There are a lot of options to read live data with iCarsoft MB2 but unfortunately i don't know what to choose and what the returned numbers mean..

Fatz

While you're waiting for someone more knowledgeable than me regarding car maintenance;
How much gas is in the fuel tank? I assume you and the "recovery man" checked that you have fuel, but if the fuel gauge indicates about 1/2 then it could be the pump in your fuel tank that redistributes the fuel; assuming you have the "saddlebag" type tank. If the gauge is at about 1/2, you can add 3-5 gallons of gas and see if it starts.

I have read of issues with the crankshaft position sensor but I thought the car would generally start after cool down.

artsym

Thank you for your reply. I will try to add more petrol, but I think chances are low...

Fatz

Don't bother adding fuel if the fuel level indicator is greater than 60% full or indicates less than 40%.

Derek Likos

I'm pretty sure it's your altenator, i had the same symptoms you did when it ended up being mine. Also might be your voltage regulator or both! When you said your car cut off acceleration its because your car went into Limp Mode (Although there are dozens of reasons for it to go into Limp Mode) which is also a symptom of a bad altenator. I might be wrong but you sure do have the exact symptoms I had when my altenator was shot dead. Hope you find out the issue, good luck!

artsym

Thank you for your reply. I gave the car to the garage. They said the issue is with fuel pump and fuel pump relay. They are changing these tomorrow. If that will not resolve the issue then will try alternator

artsym

Both fuel pump and fual pump relay replaced and the issue is now resolved. I am happy mb driver again

artsym

After replacement of the fuel pump the car has worked fine for 3 days and then just did not start. Got the car back to the garage. They said the fuel sender unit inside the tank did not send fuel from one side of the tank to fuel pump.. They replaced fuel sender unit. Got the car back and the same day it cutoff on the motorway the same way as before.. The garage now guesing that the fuel pupm / sender unit has to be genuine. If genuine parts will not work I suspect the garage will give up..

Fatz

Depending on what "non-genuine" parts are being used, what your garage said may be true. You don't show your location. Is getting OEM or OEM manufacturers' parts problematic? The problem could also be with the installation of the replacement parts. Perhaps someone else on the forum can speak to the likelihood of or if trash in the tank could be causing failure of components.

Rudeney

Did you ever replace the CPS? They often fail in extreme temps. And when the ECU gets no signal from the CPS, it shuts down the fuel pump.

artsym

I am located in the UK. The garage put 140£ and 120£ on the receipt for fuel pump and fuel sender, so I suspect they have chosen the cheapest option in store like eurocarparts.com or similar. They ordered what they call "genuine and expensive" parts now, to try. Should be delivered tomorrow.
I replaced CPS before giving the car to the garage, however replacement did not made a difference and only after fuel pump replacement the car started. Not for long though..

And this is the bit I don't understand. Once the car cuts off it would not start again. It starts again only after fuel pump/ fuel sender replacement. Do they "fill" the fuel into the pump during replacement manually and when it runs out it cuts out again?.. I would understand if due to high tempreture even new CPS would stop working, but then it should start next day after cooldown. Could it be ecu that stops sending signal to the fuel pump once it gets hot? But again it does not start after cooldown unless garade does some work on fuel pump/sender

Rudeney

You might be able to verify that it is/not the CPS. When it won;t start, pour ice water on the CPS. Also, there is an adaptation that you might want to run in SDS for the CPS. Usually it's not needed when replacing it, but sometimes it helps.

As for the possibility of it being the fuel pump, there is no priming - it sits submerged inside the fuel tank.

artsym

Putting ice would be problematic as in w209 cps in very, very hard place to reach. Wouldn't overnight stay do the same thing (after a day it still couldn't start). Also when cranking diagnostics tool shows live rpm - if it would be cps broken shouldn't it show 0 even when cranking?
Please explain more about what is adaptation and SDS as I am newbie with mercedeses? Thanks

Rudeney

Yeah, it is hard to reach, but you can use a funnel and a tube. The roadside assist guys use this trick to get failed CPS car moving so they can be driven to the shop without a tow. If live data shows RP during cranking, then it's not the CPS. SDS = Star Diagnosis, i.e. MBZ's diagnostic and workshop system that the dealers use (though you can buy a Chinese clone/copy for $300-$700). It has steps to properly adapt a new CPS.

artsym

Thank you! SDS sounds like a very useful tool to have. Probably I should have bought it instead of iCarsoft...
Today I​​​​​​ have got a call from the garage that genuine fuel pump fixed the issue. Hopefully they are right (hard to believe though) and I will not need to be towed yet another time (it would be the 4th time). Fingers crossed...

Rudeney

What brand fuel pump did you have installed before?

artsym

I don't know to be fair. The garage bought the pump and there wasn't specified a name on their receipt.

artsym

Mechanic said that "Bosh" parts did not work (not sure but probably both fuel sender and fuel pump) and that he couldn't figure out why. They seeked mercedes specialist advice and he adviced them to use genuine parts. Mercedes parts did work and so far car is working fine.

I have one last question: is it good for engine if i will use premium petrol (bp ultimate) all the time ? My priorities are as follows: healthy engine - highest, performance - medium, price - lowest

2MCHCAR

Is the new CPS currently installed on the car Bosch, OEM Mercedes (these two work in my experience) or other (I've heard nothing but bad things about non-Bosch/Mercedes CPS)? When my indy replaced the CPS the first time, he used a Bosch replacement and that lasted for about a year. The second time I replaced it myself using a OEM Mercedes CPS (which I think is manufactured by Bosch too) and it lasted about 3 years. My car is supercharged so it might be generating more heat than usual, YMMV.

Rudeney

I am pretty sure that Bosch is the OEM for the fuel pump and sender. However, you have to be very careful buying car parts these days. Amazon and eBay (and some deep discount sellers carry "fake" Bosch (and other name-brand) parts. It is quite possible that your mechanic bought from a supplier that is getting fake parts. It's a huge problem these days, and ironic because Amazon and eBay are all over fake "luxury" goods like Prada, Gucci, Rolex, etc. but they simply don;t understand auto parts, so it's the wild west out there.

artsym

Currently I have got Bosh CPS (replaced myself). After some googling I agree that Bosh is actual genuine manufacturer for fuel pump and sender for W209.. Therefore mechanic probably bought "fake" parts initially trying to save some money... As a consequence both of us ended up loosing a lot of time, money and nerves..

cm60k

"Bosch" & "Pierburg" are the OEM's fuel pumps,

they have almost lifetime contract with MB,

have to be careFULL to get any of them,,

aftermarket & Chinese flows around as..!,,

[--Fakey Fakey--]..

-;ZAYED;-

MacVidMB-V8

Sounds like you bought a bunch of parts you didn't need. Time for a new garage.

cm60k

Indeed..