• Bosch LSU4.2 WBO2 Sensor
Holley replacement WBO2 sensor. #554-101
The actual wire (cable) length is 25", not including connector or sensor body.
http://www.not2fast.com/instrumentat...03mar21eng.pdf (Bosch LSU4.2 WBO2 Sensor Specifications)
• NTK L2H2 WBO2 Sensor
Holley replacement WBO2 sensor. #554-100
The NTK WBO2 sensor is slightly more accurate, withstands higher
exhaust heat (forced induction) and is compatible with methanol/race fuels.
The actual wire (cable) length is 25", not including connector or sensor body.
FYI: The NTK WBO2 sensor is now the same length as the Bosch WBO2 sensor.
• Holley WBO2 sensor 4' long extension harness
For Holley's Bosch LSU4.2 and NTK L2H2 wideband sensors. #534-199
• If a miswired wideband O2 sensor harness connector is suspected, verify it with the PIN-OUT below.
Seven wire Bosch WBO2 sensor connector:
C...brown - Calibration resistor in a shell, 2" down from connector. (Early Bosch sensors didn't have these two brown wires.)
D...brown - Calibration resistor in a shell, 2" down from connector. (Early Bosch sensors didn't have these two brown wires.)
Seven wire NTK WBO2 sensor connector:
C...brown - Calibration resistor in a shell, 2" down. (Early NTK sensors had a shorter harness without these two brown wires.)
D...brown - Calibration resistor in a shell, 2" down. (Early NTK sensors had a shorter harness without these two brown wires.)
Eight WBO2 sensor wires from ECU, at sensor connector (Bosch & NTK):
Eight WBO2 sensor wires at the ECU P1A connector (Bosch & NTK):
WB1 HTR +......A34...orange
WB1 HTR -......A9....yellow
(Optional 2nd WBO2 sensor wires are pinned the same, at Dominator ECU P2A & at sensor connector.)
"HTR" ....= heater
"COMPR" = compensating resistance
"IP" .......= pumping current
"VS" ......= voltage source
"SHIELD" = drain wire
"HTR+ & -" ....= sensor's heater
"COMPR1 & 2" = calibration resistor
"VS-/IP-" ......= common ground
"IP+" ............= current source to sensor
"VS+" ...........= voltage input from sensor
Wideband O2 Sensor Notes:Originally Posted by Holley Tech Dept.
• If configuring a new Global Folder or changing to a different wideband O2 sensor type (Bosch/NTK), be sure to leave the WBO2 sensor(s) disconnected, until you've programmed the correct "Wideband O2 Sensor Type" in the EFI software - Engine Parameters (in System Parameters). According to the warning label on new WBO2 sensors, if the ECU is powered on with the wrong WBO2 sensor selected, damage will occur. Aside from correct software programming, ensure there are no ignition misfires or exhaust leaks upstream of the WBO2 sensor(s).
• Large duration (race) camshafts will exhibit a fluctuating AFR/false lean condition at idle & low RPM, due to their significant amount of overlap. This also happens if there isn't a sufficient length of exhaust piping beyond the WBO2 sensor(s), due to the WBO2 sensor being near an open exhaust pipe (ambient air contamination). To rectify this, enter the Closed Loop Parameters (in System Parameters), and set the "Enable RPM to Enter Closed Loop" high enough to ignore this idle/low RPM condition. You'll then need to manually tune the idle area in Open Loop mode.
• The Advanced Control (1-5) sets how fast the Closed Loop control operates. 1 is the slowest and 5 is the fastest. (The Avenger & Terminator hand-held controller calls this the "Closed Loop Speed".) This depends heavily on where the WBO2 sensor is located in the exhaust system. The further away the WBO2 sensor is (away from the engine), the lower the number should be. If Advanced Control 4 or 5 is selected, one must ensure the ECU isn't oscillating the Closed Loop operation. Viewing a datalog is helpful. I experienced a condition where the actual AFR often "lagged" momentarily, behind the Target AFR. I fixed it by changing the Closed Loop Advanced Control to 5. My WBO2 sensors are located in full-length header collectors.
• If you suspect a failed WBO2 sensor, and your Fuel Table is well tuned, you can disable Closed Loop (in System Parameters), and the engine should run fine until a replacement WBO2 sensor arrives. You can do this to determine if the WBO2 sensor is at fault (at least at idle), because in Open Loop mode, the ECU ignores the WBO2 sensor. So if the engine starts running good in Open Loop mode, you've found the problem. Just ensure that you don't disable Closed Loop mode while the Learn Table is corrupted from a failed WBO2 sensor. Clear the Learn Table (if the percentages are erroneous from their nominal values), or upload the last "known to be good" Global Folder. Also, if the ECU detects a WBO2 failure, it will go into Open Loop mode.
• If you experience a failed WBO2 sensor on a fairly new EFI installation (low miles), ensure the current WBO2 sensor location isn't causing damage by exhaust condensation thermally shocking the sensor at startup and/or during the warmup period. If you suspect it is, install a sensor bung at a better location, use a taller O2 sensor bung or use an Innovate Motorsports HBX-1 to move the sensor probe out of the direct exhaust stream. I've been successfully using HBX-1 Heat-Sink Bung Extenders for many years.
↑ This is referring to the "wet" gases flowing through the exhaust system while the engine is cold. On most vehicles, you can literally see water spitting out of the tailpipe(s). It's imperative to prevent this water from contacting the WBO2 sensor, because it will thermally shock the heated sensor. OEM engineers go to great lengths to locate the WBO2 at its optimum location. Anyway, a poor sensor location can actually blow water directly at the sensor probe. Look at the routing direction (angle) of the exhaust pipe just ahead of the sensor. Does it "direct" the water right at the sensor or away from it?
• Diagnose the following:
All sensor values correct on Data Monitor?
Failed WBO2 sensor corrupted Learn Table (unusual %)?
Exhaust leaks upstream of the WBO2 sensor?
Ignition misfire? (WBO2 sensor will read lean.)
Battery/charging system functioning properly?
Consistent fuel pressure? (Disconnect vacuum hose to measure static psi.)
Inspect wire harness/connectors for damage and ensure it's not near any high voltage components.
• At key-on (initializing) and heating, the WBO2 sensor "LED" status indicator is yellow.
Then there shouldn't be any "LED" status indicator at all (especially when engine is running).
The WBO2 sensor heating cycle will time-out (key-on/engine-off) if the engine isn't started.
When the WBO2 sensor heating cycle times-out (key-on/engine-off), it will display "init".
http://documents.holley.com/techlibr...__statuses.pdf (Sensor Diagnostics & Statuses)
http://forums.holley.com/showthread....8295#post48295 (Ensure battery is fully charged!)
Key-on/engine-off & cold, the NTK WBO2 sensor displays about 29:1 AFR. The Bosch WBO2 sensor displays about 35:1 AFR.
After turning the engine off, exhaust gases need to dissipate before seeing these full lean AFRs (key-on/engine-off & cold).
* Ensure you're using the latest EFI software & ECU firmware (Link); it has "Oxygen Sensor Control Updates" (Link - HEFI_1589.eep).
https://www.holley.com/document/tech...__statuses.pdf (Sensor Diagnostics & Statuses)
http://documents.holley.com/techlibr...10555rev17.pdf (Holley EFI Wiring Manual & Diagrams)
http://forums.holley.com/showthread....ist-Holley-EFI (Troubleshooting Checklist - Holley EFI)
http://www.youtube.com/watch?v=s3R8whD3ZWg (Interesting wideband O2 sensor diagnosis - it works!)
http://www.youtube.com/watch?v=onbjzEOZtMs (Another wideband O2 sensor test - same test procedure.)
http://forums.holley.com/showthread....1537#post71537 (Additional WBO2 Sensor Heating & Status Information)
If testing the WBO2 sensor key-on/engine-off, the sensor heater will time out, so you'll need to work fast.
If you need more time, the WBO2 sensor test can be performed with the engine running in Open Loop mode.
Originally Posted by Klaus Allmendinger, VP of Engineering, Innovate Motorsports