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Zac
06-12-2014, 13:52
hello all,I have this error on this smart 451, DTC 20781 bed with delphi, the car does not exceed 2500 rpm, what do you think ? I was thinking about the mass air flow sensor...

silven
06-12-2014, 14:10
But likely the egr stuck open partially if not take turns and does a bit of black smoke ? that

amen
06-12-2014, 19:51
To me ? success and was just the mass air flow sensor went.

Zac
07-12-2014, 11:57
Instead,always with delphi, but in the mode? support obd read error p1400

jolidj
07-12-2014, 12:15
p1400 should be the egr.

silven
07-12-2014, 12:28
Instead,always with delphi, but in the mode? support obd read error p1400
I confirm what I have already? said check the egr smontala or leak, disassemble likely to be locked partially open results in various errors in both mass air flow sensor that pressure turbo.
P1400 EGR Calibration: lower Position

Zac
07-12-2014, 13:12
you definitely will be the egr, it does not produce smoke as you say silven, for? f? a smell excessive gas.....

Zac
07-12-2014, 13:21
today afternoon I remove and I want to know.

silven
07-12-2014, 14:11
you definitely will be the egr, it does not produce smoke as you say silven, for? f? a smell excessive gas.....

? she ? you...you say that happens often on this car of my customers do not ? past harmless anyone..to this problem

Zac
07-12-2014, 22:24
I started to remove everything,it was that the collector with spiral inside full of deposits.... have not yet managed to pull the body of the egr why not go out.... there is a bracket behind and I guess I have to take it off....but we are working really bad there is not space...

Zac
08-12-2014, 11:44
I have taken apart and cleaned everything,there continues to be the error and the machine, and always block

Zac
08-12-2014, 13:16
but with the car in motion from a standstill,should not aspire to the tube of the egr ?

silven
08-12-2014, 20:59
but with the car in motion from a standstill,should not aspire to the tube of the egr ?

Which tube do you mean... I am smart I know of only egr valves and electronic control,doesn't it ? that you confused with the butterfly "stop"

Zac
08-12-2014, 23:02
the smart ? a 451 of 2011, the egr valve with a control by the solenoid valve, vacuum...

amen
08-12-2014, 23:14
So I would say that you would certainly have a suction from the tube, I would try with a syringe, unless you do not have the chance? try another solenoid valve, or maybe c ? some tube with a slit in the vacuum system.

Zac
08-12-2014, 23:16

baraldino
09-12-2014, 00:04
These errors are bastard
Graphic errors Mercedes
2087 - [1] to Check the component air Filter. Air filter dirty

silven
09-12-2014, 03:53


I can't see it why? I still requesiti but I understood what'?... I'm at the point I know that you need to check the turbo,lever tube air inlet and see that it is not loose, the impeller or blocked,if you say that you feel a smell incredible I would not be him that you're leaving...

Zac
09-12-2014, 23:06
as for me, I stink I was thinking that maybe it could be the fap that does not regenerate.... however, in the diagnosis, not by....

silven
10-12-2014, 21:35
as for me, I stink I was thinking that maybe it could be the fap that does not regenerate.... however, in the diagnosis, not by....

In diagnosis to see the fap if ? clogged you have to see the difference of pressure that c? between the upstream (before the cap) and the downstream (after) you should have the data on the tester,which basically reads the data from the sensor to the differential ? the one that started the regenerations when it clogs up. But according to me you have a problem with the turbo...

Zac
10-12-2014, 22:57
do you believe that you may be seized of the post command ? I own the turbo gone ?? the car has almost 70,000 miles...

silven
10-12-2014, 23:16
do you believe that you may be seized of the post command ? I own the turbo gone ?? the car has almost 70,000 miles...

On the smart usually you loose the shaft and the impeller wears on the body and is not able to do pi? pressure to explain in simple words... but you have experience disassembling the hose air inlet (the one that comes from the filter mass air flow sensor) could sneak a finger to check the slack on the shaft should be of medium milllimetro to the maximum if, instead, you feel a backlash of 2 mm or more? or do you feel it hard to turn ? gone...

Alessio93
11-12-2014, 11:51
I would check the tubes, injectors, and intake air and break off for about 15 minutes the battery

Zac
12-12-2014, 18:48
I made another diagnosis with the tex... error p2078 sensor (pressure difference)

Zac
12-12-2014, 18:49
the reason for the smell was why? non-regenerating the fap, and then will be intasatissimo here solved the mystery

silven
13-12-2014, 19:10
the reason for the smell was why? non-regenerating the fap, and then will be intasatissimo here solved the mystery

You are hoping that you have not shot much with the fap clogged, that is where the turbines suffered the same... for the back pressure that is created in the delicate post of the turbo.

Zac
13-12-2014, 19:50
You are hoping that you have not shot much with the fap clogged, that is where the turbines suffered the same... for the back pressure that is created in the delicate post of the turbo.

with the car not around I.... and then I was given from the very beginning, has come a long way

Zac
17-12-2014, 19:59
replaced sensor pressure difference of the particulate filter and all ok :cool:

silven
17-12-2014, 21:16
replaced sensor pressure difference of the particulate filter and all ok :cool:

Well..problem solved maybe next time make a diagnosis with a tool "serious" you avoid a lot of trouble...

Zac
17-12-2014, 22:40
well mine had given me the code.... without explaining what that was, however,

silven
18-12-2014, 01:44
well mine had given me the code.... without explaining what that was, however,

Only that, as you said initially, he put a 1 in the ir? in the end 20781, however, was 2078, it becomes a whole other thing...