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Product # 4378

  • 2-1/16" (52.4mm)
  • Digital Digital
  • 6:1-20:1 AFR
  • Digital LED
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Knowing the exact air/fuel mixture running through your engine is the most important factor to extracting the highest levels of performance and durability. Not all wideband gauges are created equal. AutoMeter utilizes an advanced calibration method that automatically calibrates your gauge on every startup to assure you of the highest degree of accuracy over the entire lifespan of your sensor (no free air calibration is ever necessary). Compatible with nearly all fuel types, the AutoMeter Pro Wideband has a configurable display to pinpoint the exact range you want to keep an eye on. An advanced peak recall function and lean warning system make sure you’re safely making power, whether on the track or on the street. An automatically dimming display tailors light output for any condition. Data logging output is included for one wire or two wire systems in both lambda or AFR. Our specially designed O2 sensor and wiring harness are included for ease of installation. Quite simply, there isn’t a more accurate or easy to live with wideband gauge available on the market.

Feature Points

  • Gauge kit includes custom tuned .1 AFR Resolution Bosch LSU4.2 Sensor, 8ft. wiring harness, 304 stainless steel weld-in bung, mounting hardware, and detailed instructions for installation
  • 0-4v data output feed for ECU, data acquisition unit, or Laptop tuning
  • User programmable range for Rich/Stoic/Lean conditions
  • Peak recall/memory
  • 10:1 to 20:1 AFR range for gasoline applications
  • 12 and 16 volt compatible, compatible with nearly every street car or race car electrical system
  • User Programmable Warning Function
  • Display data in Lambda or numerical A/F ratio

Sending Units

  • 2243


  • M18X1.5 Fitting and Plug

Wire Harness

  • 5232

Mounting Hardware

  • 2230
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Does this work with other fuel like e85

Asked by: Colorado Steve
Thank you for your question. You can use this with Gasoline, Methanol, Ethanol, LPG, CNG, and Nitrous.
Answered by: Steve from AutoMeter
Date published: 2019-12-12

Do you need to buy a program for your laptop 

Asked by: Badrag93
Thank you for your inquiry. All normal functions of then 4378 are controlled by the push buttons on the dial face. No connection to al laptop is needed. The gauge does have an analog output, which can send information to a data acquisition device.
Answered by: Jim from AutoMeter
Date published: 2019-12-02

Just want to confirm this comes with the lsu4.2 sensor or lsu4.9? If it is 4.2 can it be changed to 4.9?

Asked by: Simbad
Thank you for the question. This unit comes with the 4.2 sensor and is only compatible with that 4.2 sensor. It cannot be used with a 4.9 sensor. If you want a gauge with the 4.9 sensor, I would recommend our Pro Plus models, such as #4397: https://www.autometer.com/2-1-16-wideband-pro-plus-w-sensor-sport-comp-6047.html
Answered by: Zach from AutoMeter
Date published: 2019-11-05

Is this comparable with 16 volt battery system

Asked by: Riko
Thank you for your question. Yes, this will work on both 12v and 16v systems.
Answered by: Zach from AutoMeter
Date published: 2019-07-09

What’s the difference in the air to fuel gauges between the plus and just the pro?

Asked by: Chief sparkey
Thank you for your question. The Pro gauges use the old Bosch 4.2 O2 sensor, the Pro Plus gauges use the newer Bosch 4.9 sensor.
Answered by: Zach from AutoMeter
Date published: 2019-07-09

Hi, what are the afr vs voltage outputs [ultralite wideband] for connecting to an ecm please eg. 0v 10 afr 5v 20 afr

Asked by: Grant Pratt
Thank you for your question. It is the same as your BGD range. Your BGD low setting is your 0v output and your BGD high setting is your 4v output. If you change your BGD high or low, it will also change your 0v and 4v output. The 0v and 4v can be set, everything in between those two settings changes to keep maintain a linear output.This is also explained under the BGD Range settings section of the instructions here: https://www.autometer.com/media/manual/2650-1143.pdf
Answered by: Zach from AutoMeter
Date published: 2019-04-05

Where can I find the Data Logger signal output chart for this product?

Asked by: mavrick
Thank you for your question. I believe this article may answer your questions: https://www.autometer.com/resources/index/faq_view/id/83
Answered by: Zach from AutoMeter
Date published: 2019-01-04

What's the difference between the pro model and the pro plus?

Asked by: Alex14.7
Thank you for your question. Pro uses a Bosch LSU 4.2 sensor and Pro Plus uses and Bosch LSU 4.9 sensor.
Answered by: Zach from AutoMeter
Date published: 2018-10-15
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