Lower than normal dwell readings

[CFI]

I just checked my FV dwell readings after a two hour drive. It’s varying from approx 28% - 38%. Am I running too rich or too lean?

[Bitsyncmaster]

I just checked my FV dwell readings after a two hour drive. It’s varying from approx 28% - 38%. Am I running too rich or too lean?

Your still running at the proper 1.00 Lambda. It's just that the setting is not centered so your cold start and running until it goes closed loop will be leaner than if you had it centered as designed.

[CFI]

Your still running at the proper 1.00 Lambda. It's just that the setting is not centered so your cold start and running until it goes closed loop will be leaner than if you had it centered as designed.

Thanks. That would explain the rough cold starts lately. I’ll try to bump it up a little.

[David T]

The mixture screw adjustment is VERY sensitive. A tiny bit of a turn is all that is needed. Then plug the hole with a piece of electrical tape and wait till the reading settles down. When you are done put a proper plug in. The adjustment should only be done on a freshly tuned up motor with everything working perfectly and warmed up.