Hi,
I am getting a check electronics light in my E300 Diesel with 214K. I scanned the codes and I am getting an Intake Air Temperature sensor performance problem, and also a throttle position sensor malfunction. I called multiple dealers and when i asked them about a Throttle Position sensor they all got confused because they could not find one for my model. They said that the gas models had them, but the diesel models they couldnt find anything on them. Does anybody have any suggestions? How about the Intake air temperature senosor, should i replace it or replace the filters and other parts. any suggestions? PLZ Help

 

Is it a W124 95 or a W210 96 and above? If 96+ post the code numbers.

On the W210 the TPS is on the drivers side next to the fuse box. On 96/97 it has some mechanical linkage, on 98/99 it is strictly fly-by-wire. Not a high failure part. Check that the throttle cable and electrical connectors are both good.

The IAT could be a bad MAF. The codes will tell.

 

The code for the IAT are P0111(IAT sensor 1 ckt Rng perform) and P0120(Throttle /pedal position sensor a ckt malfunction). I got a new IAT sensor today. I will replace it and clean the headers. I looked at the TPS and it looks ok to me. I havent check any electrical connections, I will try that as well. The MAF is also something to look into. I will try all these thing over the weekend and get an update. thank you for the post

 

By the way, it is a W210. A 96 model. When i purchased it 3 weeks ago, it kept on stalling and giving me glow plug and injector codes. I replaced the k40 relay and they have gone away and the car has not stalled yet. I left it running in the driveway for a few hours and it ran fine. I have not driven it on the road yet, since i did not want to get stranded. I also have an 81 240 D, and an 87 300SDL.

 

The Check Engine light wont go away. The check engine light is on because of the TPS and the Check engine electronics light is on because of the IAT sensor.

 

I'm not really familiar with either of those codes. Both are circut malfunctions though whihc usually means they are not reporting to the ECU when expected..

Try cleaning the MAF with a CRC spray cleaner made for that purpose and see if that help?

The TPS is a VERY low fail part. Maybe check that the throttle cable and mechanical linkage it activates aren't binding?

Sorry, is all I can think of right now.

 

I replaced the IAT sensor and that code went away. The only thing left to do is the TPS. I am not sure what to do about that.