Mercedes-Benz Parts Catalog Mercedes-Benz Accessories Catalog Mercedes-Benz Technical Articles Mercedes-Benz Tech Forums
 
Follow Pelican Parts on Facebook Follow Pelican Parts on Twitter Follow Pelican Parts on Instagram Follow Pelican Parts on YouTube Follow Pelican Parts on Pinterest Follow Pelican Parts on Tumblr
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Intake Air Temperature Sensor Replacement
 
Bookmark and Share

Pelican Technical Article:

Intake Air Temperature Sensor Replacement

Steve Vernon

Time:

15 minutes15 mins

Tab:

$10

Talent:

*

Tools:

Hands

Applicable Models:

Mercedes-Benz 260E (1987-89)
Mercedes-Benz 300CE (1988-93)
Mercedes-Benz 300E (1986-93)
Mercedes-Benz 300TE (1988-92)
Mercedes-Benz E320 (1994-95)

Parts Required:

New air intake temperature sensor

Hot Tip:

Check type of connection before ordering part

Performance Gain:

Proper air to fuel ratio

Complementary Modification:

Clean MAF sensor

There are three air temperature sensors on the car; one for the engine air intake, one for the climate control system and one that shows the outside air temperature in the dash. This article deals with the engine air intake temperature sensor.

The sensor measures the temperature of the air as it travels into the induction system. The information is used by the ECU to help determine the fuel air mixture to keep the engine running correctly; whether it is below freezing or is over 100 degrees outside. The sensor is inexpensive and easy to replace; the only issue is that they made two types, a single and dual pin connector. Make sure you check the type of connection your sensor has before ordering a new one.

NOTE: The 1986 300E does not have the EFI related temp sensor. It does have an ambient air temp sensor that's used for the climate control, but not for the EFI. EFI/EZI in this car senses engine temp only.

The sensor is located in the air intake tube on the left side of the engine just above the intake manifold (red arrow).
Figure 1

The sensor is located in the air intake tube on the left side of the engine just above the intake manifold (red arrow).

Release the small clips on the end of the connection (red arrow) and pull the plug from the sensor.
Figure 2

Release the small clips on the end of the connection (red arrow) and pull the plug from the sensor. You will want to do this before you order your new sensor as Mercedes made two different types of sensors over the run of the W124. This sensor is a dual pin (yellow arrow) but they also make a single pin connection. Double check before you order.

Squeeze in the tabs (red arrows) on the sensor and pull it straight back out of the intake tube.
Figure 3

Squeeze in the tabs (red arrows) on the sensor and pull it straight back out of the intake tube.

With the sensor out you can see the wires and resistor (red arrow).
Figure 4

With the sensor out you can see the wires and resistor (red arrow). These wires will get coated with oil over the course of their lives. Some people have reported success with cleaning them with MAF sensor cleaner, but since the cleaner is more expensive than a new sensor I recommend just replacing the sensor to start with. Installation is the reverse of removal.


Bookmark and Share
Comments and Suggestions:
Vollumscope Comments: I'm looking over the 1986 300E service manual and I don't think that the 1986 300E has this EFI related temp sensor.

It does have an ambient air temp sensor that's used for the climate control, but not for the EFI.

EFI/EZI in this car senses engine temp only.
November 4, 2015
  Followup from the Pelican Staff: Thanks for the additional info. We appreciate it. I will have the article updated.
- Nick at Pelican Parts
 

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

 

[Home] [Customer Service] [Shopping Cart] [Project/Wish List]
  [Privacy Statement]  [Contact Us] [About Us] [Shipping] [Careers]

Copyright © Pelican Parts Inc. -    DMCA Registered Agent Contact Page

Page last updated: Wed 12/7/2016 03:01:16 AM