I'm helping a buddy across the country & he doesn't have a W/B. He smells fuel on cold start, and it wants to die when he puts it into gear @ colder temps in OL.....it's fine when warm & in CL; & the logs look good.

Would it be most direct for me to shorten the cold CL timer so I can get a look at the reported BLMs at colder temps since OL forces a 128/128? I don't want to play with the TF too much yet.........is my thinking on the right track? I had planned on using the "Open Loop AFR ratio % change vs. coolant temp" table shown below.

Thanks for any comments!

 

The engine may not like running at 14.7:1 when cold. I've run into this where I needed to raise the CL enable temperature just a few degrees.

Many times it just takes some playing with the after start (choke) fuel & SA, along with the CTS compensated fuel & SA.

RBob.

 

Thanks, I have tweaked the colder timing a bit & if I understand you correctly you're saying the fuel table I have listed is also something I want to look at..........good.

I absolutely agree about the colder temps needing more fuel, my question was more along the line of how can I determine where it's at without a wideband. I think forcing an early closed loop is the ticket.

Thanks again!

 

For the O2 sensor to read properly, I think it must be at a certain temperature, no? You could try getting a heated O2 like I did and closed loop comes on earlier.

 

Good idea, it does have a heated O2 though. In the absence of any other suggestions I think I'll just shorten the cold closed loop timer so I can see what the BLMs are doing sooner.

Thanks for the thought!!