sprinter 312d turbo not kicking in

[ki_saj_ng]

hi all,

this is my first post so please help the newbie :Oops:

i have a 1997 sprinter 312d with 200k on the clock.

recently the turbo has decided it will only work when it wants to. 9/10 times when i put my foot down in any gear, the turbo spools and whistles as it should but when the revs hit 2500 it wont climb any further. but the other 1/10 times it works just fine and the truck pulls like a train.

i have just serviced the truck, new oil (15/40), new oil filter, air filter & fuel filter (original merc). i have used the best diesel flush also to help keep the system clean.

i know sprinter can suffer from some sort of braking failure and usually this can cause the turbo issue to arise, i have looked over all the bulbs and wiring and it all seems spot on. BUT on idle if i press the break pedel the revs drop by 300 approx, im not sure if this is connected somehow?

also if im just idling and press the accellerator, it will rise to 2500 and stop, the exhaust at this point is chucking out loads of white smoke but when im driving and hit the 2500 limit in any gear, theres NO smoke???

i think iv covered all the scenarios but please ask and i can provide further details.

i have spoken to a few mechanics, some suggest the turbo is knackered (why does it work sometimes? why doesnt it smoke?) some just havent got a clue.

this is my work truck so without this i dont make any money, i could take it to mertrux to get it diagnosed but thought id try my luck on the forum before.

any help will be much appreciated.

thanks

SAJ

 

[Quick Silver]

hi all,

this is my first post so please help the newbie :Oops:

i have a 1997 sprinter 312d with 200k on the clock.

recently the turbo has decided it will only work when it wants to. 9/10 times when i put my foot down in any gear, the turbo spools and whistles as it should but when the revs hit 2500 it wont climb any further. but the other 1/10 times it works just fine and the truck pulls like a train.

i have just serviced the truck, new oil (15/40), new oil filter, air filter & fuel filter (original merc). i have used the best diesel flush also to help keep the system clean.

i know sprinter can suffer from some sort of braking failure and usually this can cause the turbo issue to arise, i have looked over all the bulbs and wiring and it all seems spot on. BUT on idle if i press the break pedel the revs drop by 300 approx, im not sure if this is connected somehow?

also if im just idling and press the accellerator, it will rise to 2500 and stop, the exhaust at this point is chucking out loads of white smoke but when im driving and hit the 2500 limit in any gear, theres NO smoke???

i think iv covered all the scenarios but please ask and i can provide further details.

i have spoken to a few mechanics, some suggest the turbo is knackered (why does it work sometimes? why doesnt it smoke?) some just havent got a clue.

this is my work truck so without this i dont make any money, i could take it to mertrux to get it diagnosed but thought id try my luck on the forum before.

any help will be much appreciated.

thanks

SAJ

Turbo boost control unit . I had exact same symptoms on my Vito 110CDI and had done just about the same mileage.Its about the size of a matchbox with two vacuum pipes connected to it but don't know where it is situated on a Sprinter .On a Vito its just below the windscreen on the drivers side under the bonnet .Its a quick and cheap fix too as only takes a few minutes to change and not expensive .

 

[ki_saj_ng]

hi,

thanks for the reply, i know this is in the same place on the sprinter.

so it just fails and causes these silly problems?

i hope this is the fix and i can get back on the road.

thanks for your reply mate, will post back tomorrow once iv changed it!

anyone else got any suggestions?

cheers

 

[ki_saj_ng]

hi again,

today i fitted a new brake light switch to eliminate that from the equation, the outcome - FAIL!

the one fitted didnt seem like it was the original from 1997 so it has probably been changed at some point before.

another question to all sprinter/vito owners, does your truck/van rev past 2500 when standing still in neutral? mine doesnt and chucks out white smoke.

the boost control unit was £80 so i didnt buy that just yet, can anyone confirm thats what i need for sure or should i get a diagnostics done?

is there any way to do a manual fault code check on the sprinters?

cheers

 

[Quick Silver]

hi again,

today i fitted a new brake light switch to eliminate that from the equation, the outcome - FAIL!

the one fitted didnt seem like it was the original from 1997 so it has probably been changed at some point before.

another question to all sprinter/vito owners, does your truck/van rev past 2500 when standing still in neutral? mine doesnt and chucks out white smoke.

the boost control unit was £80 so i didnt buy that just yet, can anyone confirm thats what i need for sure or should i get a diagnostics done?

is there any way to do a manual fault code check on the sprinters?

cheers

The brake light switch has no relevant connection with the Turbo boost pressure.Yes my engine does rev past 2500rpm offload . The white smoke is unburnt Diesel which if your turbo boost was working you would have sufficient air/fuel mix for proper combustion and no smoke . In reality you are compensating for lack of boost pressure by stamping the gas pedal to the floor causing overfueling and because the engine cannot combust the fuel efficiently (lack of air) you will get white smoke and no increase in power .

 

[ki_saj_ng]

The brake light switch has no relevant connection with the Turbo boost pressure.Yes my engine does rev past 2500rpm offload . The white smoke is unburnt Diesel which if your turbo boost was working you would have sufficient air/fuel mix for proper combustion and no smoke . In reality you are compensating for lack of boost pressure by stamping the gas pedal to the floor causing overfueling and because the engine cannot combust the fuel efficiently (lack of air) you will get white smoke and no increase in power .

from my understanding, a faulty brake light switch could result in the turbo not functioning correctly, i know it wouldnt affect the boost but totally stop it from kicking in.

iv read that if you have the foot on the gas whilst driving and tap the brakes with your left foot the turbo kicks out, if in the case the brake light switch was knackered. maybe im wrong.

even if it didnt fix the turbo issue, i was hoping it would cure the revs dropping 300rpm issue that im also having but it didnt.

back to the drawing board, maybe il give the boost control unit a shot.

would i cause the engine/turbo any damage by driving it in this state or can i still do short runs in it?

thanks

 

[Quick Silver]

from my understanding, a faulty brake light switch could result in the turbo not functioning correctly, i know it wouldnt affect the boost but totally stop it from kicking in.

iv read that if you have the foot on the gas whilst driving and tap the brakes with your left foot the turbo kicks out, if in the case the brake light switch was knackered. maybe im wrong.

even if it didnt fix the turbo issue, i was hoping it would cure the revs dropping 300rpm issue that im also having but it didnt.

back to the drawing board, maybe il give the boost control unit a shot.

would i cause the engine/turbo any damage by driving it in this state or can i still do short runs in it?

thanks

No you will not cause any damage but you will need to compensate for any lack of power when pulling onto roundabouts etc and give yourself a bigger safety margin especially as you say this is intermittent and not constant .

 

[ki_saj_ng]

hi,

i have changed the boost control unit with a new one from merc but still the same issue.

anyone else have any ideas? injectors?

thanks

 

[ki_saj_ng]

hi again,

just an update for you guys eventhough iv had no response from anyone other than Quick Silver, thanks mate.

ok having changed some parts and still no positive result, iv had the sprinter diagnosed and no faults were found, no fault codes whatsoever.

however, the diagnostic man said there was a huge delay in getting the live diagnostics. in a normal case where the ecu should report back to the scanner it takes 2-3 seconds but in my case it took 3-4 minutes.

he reckons there may be an ecu fault but we can not be sure on this, any suggestions?

also once we got the live diagnostics results up, all the runnings/temps/readings were spot on apart from the following two:

oil level switch - NOT OK

brake lamp switch via CAN - ON (always on with or without brake pedal)

these werent detected on the fault codes but just in the general running of the engine. could these two problems be my problem? any feedback on this would be appreciated.

i have taken out the ecu to make sure its not damp or anything like that, otherwise i may have to get that inspected. does anyone know if i can just replace with another one or are they coded specific to each van???

thanks

 

[ki_saj_ng]

Been working on the truck again today!

Noticed that if I feather the accelerator pedal,it revs fine past 2.5k but if I just floor it there's a good chance it'll hit the 2.5k wall!

I'm starting to think maybe this is the turbo getting stuck? Is there any chance this could be the case?

Help please!

 

[ki_saj_ng]

bump, any suggestions? anyone....

 

[nickcc101]

Not sure on a sprinter but the problem could be related to the air inlet hose collapsing. Try dropping the hose off and see if it cures the problem. Inlet hoses can get contaminated with oil internally which causes them to collapse under load.

 

[ki_saj_ng]

hi,

Do you mean the hose that leads to the turbo from the filter or the one from the intercooler to inlet mani?

Iv had a brief look at them all and they look fairly clean,only a little oil residue which is normal!

Cheers

 

[nickcc101]

Just drop the hose off nearest to the turbo, if this cures the problem then its one of the hoses that is closing up. Used to be a common fault in years gone by.

 

[ki_saj_ng]

hello,

It's not the hose,doesn't make a difference whethers it's off or not.

The turbos not sticking,I can see the blades spining when the pipes off,even when the engine stops at 2.5k.

I think turbo seals have gone,had another mechanic look at it and he said eventhough the turbos running fine,it's passing oil hence the smoke!

If this is the case,how would the ecu know to put it into limp mode and limit it at 2.5k???

Confused on what to try next? New turbo £300 or rebuild this one?

Thanks for everyones input so far.

 

[ki_saj_ng]

hi all,

this things making me go nuts, no idea what to try next?

i went to Damas (chesterfield) in the sprinter to see if they could sort it out, they reckon the turbo is spooling and boosting fine but is letting oil through which is causing the smoke so a new turbo is needed.

how would the ecu know if the turbo is letting oil through? and as a result cut off the turbo? anyone shed some light on this?

whilst driving today, it was driving fine and i had reached 3k+ rpm in 2nd and all of a sudden turbo dropped and the sprinter decelerated back down to 2.5k rpm. this cant be a result of oil passing through in the turbo can it??? surely this is an electrical fault???

HELP!!!!

iv got the diagnosis man coming out tomorrow again to see if theres any new error logs.

cheers

 

[ki_saj_ng]

update,

fitted a new turbo today and am still having the same problem.

during driving, if i hit the 2.5k rpm limit theres no smoke but when standing if i hit the 2.5k limit theres clouds of smoke.

i need help, someone please help as i dont have any other ideas now.

???????????????????

cheers

 

[nickcc101]

Just guesswork without looking at your vehicle. Could be the fuel injection pump. Suggest taking into Diesel specialist (not MB) as you could end up changing parts "just in case" a very expensive way to go.

 

[mitch23000]

did you check the clutch pedal sensor, this can also cause the limp mode problem, try reving your engine at idle the try pressing the clutch pedal if this allows the revs to raise this is probably not the problem but if there is no change then its not working and its only an easy and cheap replacement so should be an easy fix hope this helps, wish i new this before i changed my turbo, boost pressure sensor, pipes throttle position swith brake switch etc was the last and cheapest but did work hope this helps
gaz...

 

[zeddar1000]

bump, any suggestions? anyone....

don't know if you still have that problem but it could be your belts and pulleys. try to spray anti belt slip on them and see if it improves. if it does, change them.
that worked on mine