Lean tip in despite o2 clamp - Miata Turbo Forum - Turbo Kitten is watching you test compression.

messiahx · **Lean tip in despite o2 clamp**

Alright, I will admit I haven't checked the o2 clamp to make sure all is in order yet (I left it at the settings it came with and I will do this tomorrow), but...

I'm getting lean tip in. At any RPM that will make full boost. The easiest way to bring it out is to give it part throttle up to 4500 RPMs in second or third and then floor it. It spools up super quick (running ~8psi) and about half the time it will go lean enough to cause some ping (I can hear it) and then AFRs settle out.

How I've solved this is the past is to add in a lot more fuel below my target boost in the additional injection map (more than would be needed for a 12:1 AFR at those lower parts of the map). That solution is not working as well this time, and I'm not sure it will solve the problem. I have also tried the Acceleration map today, though I don't know if it's working, or if it's function is impaired since I wired my MAP sensor into the TPS input.

Does anyone have any suggestions on this? Basically every time I increase boost I spend more time trying to tune out this tip in than I do anything else. Thanks!

Prospero · 07-17-2009, 10:24 AM

Sounds like you need to set your O2 clamp to turn on earlier. Also, depending upon where you mounted it; make sure you don't have too long of a vacuum line or one that is too soft. I used a copper line a year ago when I just could not get the clamp to work right... the rigid line made a great improvement.

Cheers,
Matt

Quote:
	Originally Posted by messiahx Alright, I will admit I haven't checked the o2 clamp to make sure all is in order yet (I left it at the settings it came with and I will do this tomorrow), but... I'm getting lean tip in. At any RPM that will make full boost. The easiest way to bring it out is to give it part throttle up to 4500 RPMs in second or third and then floor it. It spools up super quick (running ~8psi) and about half the time it will go lean enough to cause some ping (I can hear it) and then AFRs settle out. How I've solved this is the past is to add in a lot more fuel below my target boost in the additional injection map (more than would be needed for a 12:1 AFR at those lower parts of the map). That solution is not working as well this time, and I'm not sure it will solve the problem. I have also tried the Acceleration map today, though I don't know if it's working, or if it's function is impaired since I wired my MAP sensor into the TPS input. Does anyone have any suggestions on this? Basically every time I increase boost I spend more time trying to tune out this tip in than I do anything else. Thanks!

messiahx · 07-17-2009, 12:55 PM

I actually asked that question in another thread (is my vacuum line too long?) and was told that was very likely not the issue.

My o2 clamp is next to the ECU and the vacuum line running to it is probably 8-10ft is length total since it is tee'd off the line for the boost gauge and runs through the interior. The MAP sensor is back there as well. It's just standard rubber hose.

I guess I'll first make sure the clamp is set properly and then move the sensor and clamp up to the dash which should remove 5ish feet of line if that doesn't work.