Hi Guys, just before I take my van back to merc and get stung for £70+ per hour, have you any ideas what the probelm is, plz

 

Van is a 54 plate Merc Vito, it starts 1st time everytime and runs like a dream, but intermittently it just looses revs whenever it fancies, I can be driving at 30 and it just cuts out , all electrics stay on and engine doesnt stall, its like a rev limiter kicking in? Last week down the m6 it just lost revs and I had to drive home at about 15 mph, it then just decides to kick in again then off she goes, sometimes several times a minite, It has an electronic key and that sometimes get dust inside and the van wont start, once cleaned out its fine. just been to the shops in it now and it was fine

 

Its been to the local mechanics and he has ran a diagnoistics and nothing coming up, he replaced the air/fuel filters and said it may be an injector fault, so took it to an injector place and they said it was fine,they said try an auto electrician on the electronic ignition, he said all was fine??

 

so last ditch help before Merc if you have any suggestion where to start looking

 

CheerZ

hi bud,

 

if it limits to around 3000rpm then I would suspect a faulty MAF - if it is just a general lack of power then it is going into limp mode which shuts the turbo off - a variety of things can cause this - air leaks in the intake system, EGR valve faults, vacuum faults to the turbo regulator transducer, blocked cats etc which all affect the boost pressure.

 

really it needs a run with a diagnostic tool that can check live data to see what boost pressure etc is being seen by the ECU if no fault codes are stored (which would in itself be unusual if it is going into limp mode!)

CheerZ Paul, sounds like a trip to Merc then :crying: hopefully something minor, but they know how to charge

 

Thanks bud

ive got some vaseline i can send up for ya lol

 

must be a common thing to happen as my mate had a merc van many moon's ago and the same thing was happening, turned out to be a maf

Are there not any local non-dealer merc experts that would be able to plug into it with Star and roadtest it to see if anything shows up rather than as you say £70 per hour at the dealer.

I had this problem with a 58plate 311cdi. Turned out that even tho injectors came up as been fine, once they were replaced it ran perfect again.

Similar symptoms to yours, only mine was mainly when setting off(usually at most incovenient times). It had no power at all and then burst back into life.

Try and borrow a different set of injectors and see if it helps. Then if it doea you know what you need.

ive got some vaseline i can send up for ya lol

 

must be a common thing to happen as my mate had a merc van many moon's ago and the same thing was happening, turned out to be a maf

 

Got some KY jelly thanks Al :tt2: i bought it for JAE :tt2:

Are there not any local non-dealer merc experts that would be able to plug into it with Star and roadtest it to see if anything shows up rather than as you say £70 per hour at the dealer.

 

Yeh , the 1st mechanic who looked at it works for Merc, but not commercial, he is a very good mechanic with all the equipment but nothing comes up on the diagnostics, might take it round to him again and retry, thanks matey

I had this problem with a 58plate 311cdi. Turned out that even tho injectors came up as been fine, once they were replaced it ran perfect again.

Similar symptoms to yours, only mine was mainly when setting off(usually at most incovenient times). It had no power at all and then burst back into life.

Try and borrow a different set of injectors and see if it helps. Then if it doea you know what you need.

 

mmmm, intersting? will give my man a ring now, cheerZ for that

Scrap It!!!

 

 

 

 

 

:lol:

Does it still idle properly? Maybe making things up but sometimes vans have weird limiters on them to for example stop you flat shifting. So if it sees a neutral signal or a brake light switch or "not in gear" it might limit the power output to stop you ragging the crap out of it. But if the switch is faulty it might cause no power or very little power? I know in my astra if you try and left foot brake it takes the power away because it seems the brakes are on and thinks you are stupid...

Does it still idle properly? Maybe making things up but sometimes vans have weird limiters on them to for example stop you flat shifting. So if it sees a neutral signal or a brake light switch or "not in gear" it might limit the power output to stop you ragging the crap out of it. But if the switch is faulty it might cause no power or very little power? I know in my astra if you try and left foot brake it takes the power away because it seems the brakes are on and thinks you are stupid...

 

My van does this as well, bloody annoying!

Scrap It!!!

 

 

 

 

 

:lol:

 

:lol::tt2:

Does it still idle properly? Maybe making things up but sometimes vans have weird limiters on them to for example stop you flat shifting. So if it sees a neutral signal or a brake light switch or "not in gear" it might limit the power output to stop you ragging the crap out of it. But if the switch is faulty it might cause no power or very little power? I know in my astra if you try and left foot brake it takes the power away because it seems the brakes are on and thinks you are stupid...

 

 

Idle`s fine,but when in limp mode it only revs to 1500rpm, and your correct about the wierd limiters ,someone has already mentioned about the brake thing or some sort of sensor problem? too many electronic governing things AHHHHH.

does it reset if you switch the ignition off & on again?

Could there be an ABS fault pulling back the power as it thinks you are skidding?

does it reset if you switch the ignition off & on again?

 

Not really..No.... its hard to tell really..sometimes the same fault then other times its gone? wierd

Could there be an ABS fault pulling back the power as it thinks you are skidding?

 

 

Could be mate... sounds a good reason that, will ask my mechanic, cheerz

Well £277 later my problem is sorted.... a faulty ABS sensor and it was shutting the power to the engine down!! glad its fixed but 277quid to replace a sensor!! robbing t*ats

 

Thanks for everyones help and ideas

 

CheerZ

does it have traction controll??

does it have traction controll??

 

it does indeed :wink:

abs sensor does both dosnt it. proberly thought you were driving on snow all the time lol!!!

 

Glad you got it sorted :pint:

abs sensor does both dosnt it. proberly thought you were driving on snow all the time lol!!!

 

Glad you got it sorted :pint:

 

Yeh, thank Fook, I thought it was going to be a major problem with the engine or electrics, but still could have done without spending all that dosh :(

 

:thumbup1:

Technology is a wonderful thing until it goes wrong, have had that kind of fault a few times on the heavies, everything is linked nowadays and abs c an be the culprit for all kinds or weird faults, specially with auto boxes the likes. £277 isnt too bad for a dealer when there will be VAT on it but its still a nightmare and at least its sorted now.

 

Cheers John

Just a little update on this.....The problem wasnt the Abs sensor, the receptionist had the wrong file in front of her so infact the problem was an oil pressure sensor that had failed and it cost £201 inc vat, so happy days, van sorted and back to work again

 

CheerZ

I have a Mercedies e240cdi estate at the moment and the water temperture light came on yesterday so stoped the car checked the coolent and its fully topped up so give the sensors a shake and the light went out, I also find if you blow on them it helps to:biggrin:Just waiting for them to fail now lol