B16/14 exhaust temp sensor

[Exp21]

Ah, the engine light turned on again days ago. It's a strange behavior. But mine doesn't suffer from rpm limit. I can go above 2000 rpm with no issues.

 

[MikiBenz]

Ah, the engine light turned on again days ago. It's a strange behavior. But mine doesn't suffer from rpm limit. I can go above 2000 rpm with no issues.

Thanks a lot! Good for you.
I can drive my car without issues but the acceleration is not the same - it is delayed and the issue of rpm. Do you think the quality of diesel has anything do with this? Or the fact that I have driven the car mainly in a crowded city for months?!

 

[Exp21]

From my knowledge usually car goes into limp mode cutting rpms when there are dpf or egr issues. But there would be for sure some error codes. Did you do an obd scan on your own? Sometimes relying on what technicians say is not a good idea. If you can, check also the live values of the new sensor to see if they are plausible. About diesel quality for sure it could affect minor things, but I don't think it could be into limp mode because of diesel. Driving in crowd for months probably lead to a dpf clogging, but if it's not so severe it should be enough a long trip (at least 40-60 mins) at decent speed.

 

[MikiBenz]

From my knowledge usually car goes into limp mode cutting rpms when there are dpf or egr issues. But there would be for sure some error codes. Did you do an obd scan on your own? Sometimes relying on what technicians say is not a good idea. If you can, check also the live values of the new sensor to see if they are plausible. About diesel quality for sure it could affect minor things, but I don't think it could be into limp mode because of diesel. Driving in crowd for months probably lead to a dpf clogging, but if it's not so severe it should be enough a long trip (at least 40-60 mins) at decent speed.

According to the automechanics, both dpf and egr should be fine. They've checked. The obd diagnose is the same as yours in this thread: b16/14. The new sensor got checked too - seems fine.
It is weird, nobody has a concrete clue what could be the defect. They say it might be the circuits. It might - meaning, they have to check every wire. Crazy!
Thanks for your replies, very kind of you!

 

[Exp21]

you're welcome. It's already the third time I hear of this error code and nobody is able to diagnose it. Unbelievable. Probably there are some wires subject to damage during years, or there's to replace the cdi ecu. How many miles has yours? If you have news please let me know

 

[Exp21]

According to the automechanics, both dpf and egr should be fine. They've checked. The obd diagnose is the same as yours in this thread: b16/14. The new sensor got checked too - seems fine.
It is weird, nobody has a concrete clue what could be the defect. They say it might be the circuits. It might - meaning, they have to check every wire. Crazy!
Thanks for your replies, very kind of you!

Hi, yesterday I replaced the B16/14 sensor. But today I checked the old one (with a multimeter) and it seems fine. So I'm in your exact situation. New sensor but probably the issue is still there. Next days I'll check live data while driving to see if there are improvements. I also checked the 5V to the connector pins and I read 4,96V so it should be ok. I really don't know what to do

 

[Exp21]

According to the automechanics, both dpf and egr should be fine. They've checked. The obd diagnose is the same as yours in this thread: b16/14. The new sensor got checked too - seems fine.
It is weird, nobody has a concrete clue what could be the defect. They say it might be the circuits. It might - meaning, they have to check every wire. Crazy!
Thanks for your replies, very kind of you!

Hi, did you find the solution? I replaced sensor but trouble code 169100 is still there. Also on youtube and a french forum nobody is able to diagnose it. Thank you

 

[MikiBenz]

A little update:
My B200 seems to be fixed.
There was nothing wrong with the EGR temperature sensor. I have been driving in the city for months and the car obviously needs high speed and long runs to self-regenerate.
So, I stopped the diagnose in the computer in order to get rid of the limp mode and be able to drive above 2000rpm. Went highways for hours without pausing. Afterward, I did the DPF regeneration. All set, all good. Ultimately, the EGR system was clogged.
Good luck everybody!

 

[Exp21]

My problem is still there. EGT sensor is brand new, 5V seems to get to the connector. Does someone know what could I check next? Thank you!

 

[mioba]

I think you need get to your car to a merc indy garage or reputable dealer.
You need the car checked over properly and diagnosing correctly and fixed. 1.5 year problem seems to say chucking bits at your car isnt getting your far.

You mention the causes of going into limp mode above. nonsense. a car goes into limp mode to prevent over revving and further damage. causes of limp mode can be ALOT of things.

Just reading the post its clear the temp sensor works or you wont get a reading. Something connected to the sensor is failed hence the reading you get.

 

[Exp21]

Hi, next step will be going to the dealer, as I always do. I was just trying to get to the problem by myself for personal interest, I like diy. Car run also perfectly, so it's not an urgent problem.

Anyway I was thinking about the internal CDI module resistor, it could have failed? But testing it shouldn't be so easy I suppose.

There are many people trying to solve this trouble code in forums around europe. Nobody was able, even going to garages..

 

[mioba]

No one can diagnose the code by a forum without the car being on a code reader and live data and the operator being competent.
Exactly my point. you are trailing forums across Europe for an answer. that answer if correct will be luck.

internal CDI module resistor -
never heard of one. But please change it and tell is how you got on.

 

[Exp21]

By internal resistor I mean the fact the an EGT sensor should simply be a resistor in series with another (the internal one). If the internal one fails, theoretically you could have problems like these (and I think you have to replace the entire module).

Supposing the internal resistor has failed, and instead of 2.2 kOhm is now 5 kOhm, it could perfectly explain the non plausible values of the sensor from diagnosis.
Honestly I don't know if the cdi module can be opened and repaired.

 

[Exp21]

I found where the "Z connector" with the ground of the sensor is. It's the ground also for all egt sensors, light/rain sensor, coolant sensor, etc. So it's a vital importance component. But getting access to it seems to require removing the entire dashboard of the car (crazy job).

Do you think it's possible to build an alternative ground wire going to another ground in the engine bay?Just to get around the problem. Thank you

 

[Exp21]

Today I measured the voltage at the connector. It's 4.963V. The ground pin is at 0.037V relative to another ground on the chassis. Could this be the problem? The voltage that is not exactly 5.00 V? Thank you

 

[Exp21]

I solved the problem. I built a new ground wire for the sensor's connector. The 4.96V voltage I read was not correct and made me suspect a bad ground. So I bring the new ground to a factory ground point in the engine bay and now all seems to work. Voltage at connector is now 4.997V. Bye!