2013 cdi Multiple engine codes

[noswad]

Hello all , i really would appreciate some help please . I have had my 2013 c class cdi plugged in to obd as the engine light came on and it was running a little rough . slightly erratic idle , reduced acceleration , more than usual smell of fumes and untimely gear changes . The car hasn't gone into limp mode but I can no longer use the manual function of the gearbox . 4 codes have come up (see pic) . I have done an on car dpf clean which chucked out a good amount of gunk from the exhaust and have changed a sensor on the black intercooler air hose (not the red hose the opposite side) as i previously broke the clip on one side whilst replacing the hose as it split and this has made a slight improvement in regards to acceleration. My main concern are the last 2 codes . I've googled the codes and have seen alot of the time it just needs cleaning due to excessive build up of gunk , ive googled and tried watching YouTube videos but cannot for the life of me find a definitive location of either the throttle body or throttle sensor . Im lead to believe that the dpf itself doesn't need to be replaced as from what I have read the car would be almost undriveable if it was knackered completely. I want to try cleaning or replacing said parts personally as 1.i enjoy learning about my car and 2. Funds dont really allow me to spend x amount on a mechanic if its not needed. So any help would be so much appreciated , Thankyou .

 

[Steve@Avantgarde]

The fault is an air leak or a sensor that measures manifold pressure. You need to smoke test the system to see where that leak may be. Most likely a snapped bolt on the inlet manifold.

The DPF fault is there purely because the engine is going into limp and its turning off its regeneration cycle, so the fill time will be out of whack.

 

[noswad]

The fault is an air leak or a sensor that measures manifold pressure. You need to smoke test the system to see where that leak may be. Most likely a snapped bolt on the inlet manifold.

The DPF fault is there purely because the engine is going into limp and its turning off its regeneration cycle, so the fill time will be out of whack.

Thankyou for your reply . I was guessing the next stop might be a smoke test . I checked as many hoses that I could reach and couldn't find any splits etc . Was contemplating maybe a bad MAF sensor at the airbox ??

 

[noswad]

Thankyou for your reply . I was guessing the next stop might be a smoke test . I checked as many hoses that I could reach and couldn't find any splits etc . Was contemplating maybe a bad MAF sensor at the airbox ??

Also can you tell me the location of the throttle valve control motor please . I've read numerous posts about throttle bodies , some say its to the left of the engine and some say it's to the right and others say my car doesn't have one

 

[Steve@Avantgarde]

MAF sensors rarely fail and if they do, it effects the EGR and throws a code for that as well. A failed MAF wouldnt bring up an leak fault code, thats measured in an algorithm looking at the metered air that comes in compared to what it sees going into the manifold.

The throttle valve is underneath the inlet manifold. You'll see it from underneath rather than from above.

 

[noswad]

I see , that makes sense. I read somewhere that I would need to remove the fire wall to get to the throttle valve , do you know if this is true ?

 

[ALFAitalia]

Its not really a throttle valve of course....CDI engines don't have them.....engine speed is controlled purely by injector pressure and duration....what they are referring to when they say throttle is the shutter valve (AKA anti shudder valve).....99 percent of the time its wide open....it only shuts to make it smooth when you turn the engine off instead if getting that thud you did on old dervs....and sometimes it shuts a little bit to increase vacuum and flow through the EGR. Some derv tuning places remove them completely for more flow....not recommended through and they can help stop a diesel engine runaway.

 

[noswad]

Ive just been watching videos as im intending to do an off car dpf clean and during this particular video i found this , Is this the "throttle valve" that that can get gunked up ?

 

[noswad]

So I've just completed a smoke test at home after receiving the smoke machine and initially the leak was coming from this hose connected to the turbo (see pic 1) so I took it it off and gave it a clean as it was a little mucky and replaced it . All fine until I see a small amount of smoke coming from this connection (see pic 2) . It doesn't look like this part is replaceable ?

 

[noswad]

My apologies for a probable stupid question but is this the cat or the dpf please ?

 

[mioba]

DPF

 

[noswad]

Thanks haha . I can't seem to get it out from the top or bottom . If I try from the top I'd have to remove that bit above it but there are 2 hex bolts that i cant really get to and there's a control arm connected and dont want to displace it . If I try from the bottom I'd need to remove part of the steering shaft

 

[noswad]

Also , while its already off the car can the cat be cleaned internally too with dpf cleaner ?

 

[alexanderfoti]

You have to split them and rotate one out from the bottom, it's a bit of a faff.

The top unit is the cat, the lower unit is the dpf.

You have to inject smoke/pressure into the turbo inlet, rather than the intake pipe to the turbo. It is expected that smoke will come out from both the turbo inlet and exhaust as it flows through the system

 

[noswad]

Sorry , i dont understand , mioba said the part in the picture , what you say is the top part (connected closest to the turbo) , is the dpf and your saying its the cat ???

 

[alexanderfoti]

Upper component 20 is the catalyst, lower component 40
is the DPF

 

[noswad]

Are you 100% sure ? It's just i want to give both a clean but read that soaking the cat in dpf cleaner can damage the cat so want to grab a seperate cat cleaner

 

[alexanderfoti]

Yes, if in doubt, its the metal can with the 2 pipes that lead to the pressure sensor!

 

[noswad]

Well this is the thing , each can has one attached to it haha

 

[noswad]

See pics