A140 W168 will crank but not attempt to fire ???

[bas...A140]

Hi all, got some confusion here, My wife has a t reg A140, it has manual gearbox.

Anyway a few days ago went out all as normal, popped in a friends house, came out about 45 mins later and car would turn over but no attempt to fire or start,
kept trying and the same thing, went inside and rang AA man, waited 25 mins and i tried it again, started first time as usual, ran it for a few mins, all good, turned it off and started it a few times, everything fine.

So we cancelled the AA and set off on our way home, 300 yards later it died mid drive, pulled over and tried to start it for about 15-20 mins and nothing, same again turns over but no attempt to fire, not even a splutter, no warning lights or anything to say their was a problem.

AA again, this time it started after about an hour, but i waited for AA, problem gone, AA followed me home (about 10 miles) back on drive, revved it turned it off and on 5-6 times and all good, he couldn't give me any clue as the fault had gone.

Turned car off, while he sorted out paper work, maybe 5 mins and then same again would start, turns over fine but nothing.

So it seems to start after its been left for an hour, start first time in the morning, but after a run, even if you leave it an hour, wont start, wait another hour after the failed attempt and off she goes, just like normal.

Ive tried to give all the info i can, but if you need more, ill do my best.

It hasnt gone to a MB dealer yet as i got stung for £1600 for a faulty indicator, which turned out to be the cluster, £850 inc fitting the rest was them trying to find the problem, so i'm not totally convinced they have much of a clue their, i would like to go in with half an idea of what it might be.

thanks for your help

 

[Howard]

Crank Position Sensor ?

 

[bas...A140]

Crank Position Sensor ?

after reading throw a lot of threads, i thought this to, but a local garage has said, they are not usually intermittent, its a case of work or not ???

Again i have no clue about this so its just what i got told

 

[AndyPCD]

I would say crank position sensor too.

The fault is intermitant on these as it is caused by heat so they will cut out and after a period of time the sensor cools down and then this is why it will start again

 

[bas...A140]

I would say crank position sensor too.

The fault is intermitant on these as it is caused by heat so they will cut out and after a period of time the sensor cools down and then this is why it will start again

the AA man said the same, but he said he couldn't understand why after running and turning off it will instantly start again, but if you leave it for 15 minutes, it wont start, he thought the same thing and tried to get it hot while he was here, but it didnt make any difference.

Tonight i started it fine as normal, ran it for a minute and turned it of, restarted it fine, left it for about 1 hour and then went to go to the shop and same thing non-starter, but this would of meant it was cold

 

[BlackC55]

Crankshaft sensor issue 100%

 

[andymerc]

crank senor

 

[bas...A140]

i thank you, from what you guys have said, its the crank shaft sensor

So any ideas on a rough price to have one fitted, or is it a simple thing i could do myself, i'm not a mechanic but i did maintain my sons mx bike, so have a little bit of savvy.

Just looked, please tell me this guys wrong
CRANKSHAFT Sensor Replacement

 

[Howard]

Read this . Doesn't look horrendous.

Bert Rowe's-Mercedes-Benz 'A'-class information. Engine sensor locations

FWIW the best site for A class info is Albert 'Lofty' Rowes. Link below.

http://www.aclassinfo.co.uk/mypage.1.htm

 

[bas...A140]

Read this . Doesn't look horrendous.

Bert Rowe's-Mercedes-Benz 'A'-class information. Engine sensor locations

FWIW the best site for A class info is Albert 'Lofty' Rowes. Link below.

Albert Rowe, Lofty's homepage

Thank you m8, doesn't seem to bad (famous last words )

 

[bas...A140]

Read this . Doesn't look horrendous.

Bert Rowe's-Mercedes-Benz 'A'-class information. Engine sensor locations

FWIW the best site for A class info is Albert 'Lofty' Rowes. Link below.

Albert Rowe, Lofty's homepage

Thank you, doesn't seem to bad (famous last words )

 

[bas...A140]

Just a little update, got it to a garage and plugged it in, turned out to be the cam sensor ?

the garage fitted it for free (as i broke down outside )

Just wanted to say, THANK YOU all the helped

 

[Howard]

No worries.

Stick around , you'll like it here.

 

[bas...A140]

Looks like i spoke to soon, alls been fine, runs better.

But today went shopping all good, come out of tesco, started fine, into garage again started fine.

Got home and staled it getting on out tight drive and guess what NON started again

left it 15 mins and it fired up fine again.

Could i have got a new faulty cam sensor or maybe could the machine have read it wrong or maybe the crank sensor aswell ????

Or could this be a symptom of something else ???

 

[Howard]

Crank Position Sensor ...

Its weird , but not impossible that both could fail.

With the faults you have described , its almost certainly the crank sensor.

Did the garage read it on a STAR or a generic code reader ?

 

[bas...A140]

Crank Position Sensor ...

Its weird , but not impossible that both could fail.

With the faults you have described , its almost certainly the crank sensor.

Did the garage read it on a STAR or a generic code reader ?

No just a normal code reader i think, but i couldn't be sure on that, they were not a merc specialist, so think it was just a normal machine.

but they did try it 3-4 times, and cleaned old sensor and tried again, still showed cam sensor fault, after fitting new one, faults were empty, started and waited then plugged in and tried again, still nothing on the machine with any faults.

 

[AndyPCD]

I still think it will be a crank shaft sensor as the way you describe the fault is exactly the type of fault a crank sensor will produce,

Also sometimes it will not show a fault code in the system either

 

[Howard]

Pleased to hear that you replaced the CPS in the end and it has solved your problems.

 

[bas...A140]

Just a quick update, after installing the cam sensor everything was fine for about 3 days.

Then the problem returned so got the codes checked again and what do you think came up, yes crank sensor.

i will keep this short, but after a long long time of trying to extract the crank sensor after it snapped

i finally had to admit defeat and get a local garage to get the crank sensor out, anyway that was tuesday this week and since then all has been fine, fingers crossed this has solved the problem.

So a big thank you to everyone who replied, i do believe you were all correct on the crank sensor, thinking that maybe the cam sensor was faulty aswell, but the non-starting and stalling was defiantly the crank sensor.
:bannana::bannana:

bas

 

[trapperjohn]

Thanks for the feedback bas.

Heres hoping for smooth running from here on in.