I believe that I may need a new WBo2. I would like to get your thoughts.


The car has a BP4W stroked to 2.0L, Hydra 2.7. It was tuned by Jeremy at FM many years ago. When cold, the idle droop goes to zero. The car is jerky between on/off throttle.
I've attempted to calibrate the WBo2. The last step asks me to remove the hot sensor from the exhaust and slide the bar until it reads 21.5. I cant get it to 21.5. The highest it will go is 16ish.
Thoughts on this?

 

Need a new sensor or possibly your onboard controller is dead.

When driving, does the wbo2 signal show any sort of change or it is just kinda static?

 

I will data log it tonight. Im glad you suggested that it could be the on-board controller. A few months ago, when installing a hard dog roll bar, we pinched the alternator wire and fried the Hydra. Sent it to Phil at Nemesis. They repaired it. This could be a lingering issue.

 

Hydra WBO2s have a lifespan of a few years. I recommend getting the car together, driving it in closed loop through a full annual temperature range, then removing the WBO2 and setting the hydra to open loop. Replace it with an AEM or some other cheap WBO2 with a gauge so that you can monitor afterwards.

My experience is that if the WBO2 seems to lose range, then it's useful life is over.

 

Here's a data log. It looks like the oop wideband i-term value is flat at 15.3. You'll notice the revs going up and down but Im not modulating the throttle.

A while back, I fried this Hydra and sent it to Phil at Hydra to repair it.

Thoughts?

 

If the flat green line is wideband and the purple line isn't, then yeah something is definitely dead. Could be sensor, could be controller. Unfortunately it's hard to determine without putting another grossly overpriced sensor in to test. I guess make sure you have wideband "on" in Hydra first. Other than that... time to decide where you want to spend your money.

Does the sensor get hot if you were to remove it from the exhaust and turn key on? (i think this setup pre-heats even if car isn't running as long as key is on. If not, might need to run the car and see what happens if the sensor is free-air.)

 

I've gone through the same thing. Thought it was my sensor, it wouldn't respond or calibrate or even heat up. I swapped in a new sensor, it still wouldn't heat up or calibrate. Tried running in open loop and car ran extremely rich. Appears that the onboard controller went out. See my post "Hydra lean under low load". I'm going to reference it in a new thread. "New used Hydra"