how lean is ok?

[ADrewzki]

Recently did the 1g swap in my car. I kept getting the random misfire code so I did the 10k potentiometer mod and it's gotten rid of the CEL. However, logging with the pocketlogger, it shows that I'm running lean. If I don't run as lean as I'm running though, the CEL comes back on. I was wondering how lean I can keep the engine. Is it ok as long as the ECU is able to compensate? I'm planning on getting a dsmlink in the next month or so and I just need it to 'til then. Thanks.

 

[dave99gst]

Untill you get to much knock the ECU starts to yank timing - at the point ya should be ok.
Its when the ECU cant pull timing anymore that you can blow stuff up.

 

[ADrewzki]

Alright. So if my timing is still around 5-8, I'm ok? Reason why I ask is because short term fuel trim shows 17% and long term shows 12%. Just made me a little worried that I might be running it too lean. I'd hate to mess up the motor with only 1k on it. Thanks for the quick response.

 

[slickster]

Can you be too lean and have no knock at the same time? Or is it safe to say, they go hand and hand?

 

[SpoolnTsi]

Can you be too lean and have no knock at the same time? Or is it safe to say, they go hand and hand?

I guess its possible with a bad knock sensor but i think you would have knock all the time if it was defective. But anyway i dont believe thats the case here cuz it would be impossible to tune with a defective knock sensor. And with a good knock sensor, if you manage to go to lean, you will have knock, so no you cant go too lean and at the same time have no knock. The object is to go as lean as you can WITHOUT knock

 

[psychlow]

5-8 is BAD.

5 is the lowest timing can go - that's base timing.