When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have a 2007 6.0L LQ4 in my jet boat with the GM PCM and EFI. When I built it I kept the O2 sensors by placing them in the risers which are water cooled. I removed the water jacket where the O2 goes through, but at idle it still cools them off too much, so they start adding fuel until the fuel trims go to +25 at idle, then the O2 sensor finally shuts off when the PCM realizes its too cold. I want to make it open loop at idle but I am not sure how to do that. Any thoughts would be appreciated, as so far these are the only solutions I have come up with.
1. Use the PE mode. The issue with this OS is that the TPS PE threshold has only 1 option instead of being setup to go by TPS and RPM. See attached image.
2. Edit the Hex code to extend the enable PE mode table so it also goes by RPM. I spent an hour and a half to realize that this is above my head at the moment.
3. Use the shift light output, a relay and resistor to trick the motor into thinking its to cold to be in open loop when below ~1500rpm. The issue is that it looks like the max on time is 410 seconds.
4. Switch to another Operating system. The issue is that I am using the 2007 van ETC throttle pedal and TAC which are 1 year only. I am fairly confident that they will not interface with the 2003 12579405 OS that I have access to. I don`t think the 2005 12592618 OS will work with that TAC either.
5. Use lean cruise to go open loop. The issue I am having is if I set it up to go into lean cruise at idle RPM and 0 MPH since I have no VSS I don`t think it will go back to closed loop at running RPM.
Any other ways to go open loop at idle?
Does your temp in your area vary so much you can't just run OL all the time? If it's in a jet boat I can't imagine you need to run CL using narrowbands anyways.
I don`t need to run CL but it annoys me that it does not work right. For a couple years I ran it closed loop and it would smell rich by the end of no wake zones. The end of last summer I noticed that when using the boat to power my fly-board it would have a surge as it cleared out around 3k RPM, so I changed it to running full time OL. It seems to work ok, it just annoys me that I cannot get the CL O2`s to work right. I do use the boat in air temps from 100 degrees down to the 40s.
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.
OS12613248 Need open loop idle 
