Switched ACV now runs way too lean.
#1
Switched ACV now runs way too lean.
OK so in the proscess of trying to get my 87 Turbo to pass emmisions. I've been messing around with my ACV. I put it back on a while ago, and i could not get the O2 sensor to read any better then about .6 volts. My wideband was fine running about 14-13 at idle. I picked up a spare and popped it in there today. NOW the O2 sensor low enough but so does my wideband. With the combo of adjusting my veriable resistor, and my rtek, i can get the thing to idle at about 16-15 with everything tured way up, obviously that isn't really great. Even with it idleing with 15.5 AFR it will, drop to full lean at 2k rpm.
So what is causing this?????
So what is causing this?????
#2
HAILERS
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The ACV sends air directly to the sleeves inside the exaust ports.
The exaust ports are prior to the 02 sensors.
So if you had no ACV before or one that was not working right and NOT sending air to the exaust port sleeves, then that explains why things are lean NOW.
I forget right now. But I believe if you pull that small vacuum line off the top of the ACV (the only nipple that sticks straight up) off and plug the HOSE, then I thnk the relief valve will open and send the air out to the right fender instead of the exhaust ports, making for a Real reading of the mixture.
Driving down the road at WOT ...........no changes to the ACV works needed.
So a 16afr is NOT the real mixture value at idle because of the airpump air/ACV.
The exaust ports are prior to the 02 sensors.
So if you had no ACV before or one that was not working right and NOT sending air to the exaust port sleeves, then that explains why things are lean NOW.
I forget right now. But I believe if you pull that small vacuum line off the top of the ACV (the only nipple that sticks straight up) off and plug the HOSE, then I thnk the relief valve will open and send the air out to the right fender instead of the exhaust ports, making for a Real reading of the mixture.
Driving down the road at WOT ...........no changes to the ACV works needed.
So a 16afr is NOT the real mixture value at idle because of the airpump air/ACV.
#3
Yeah I was guessing i wasnt getting the real reading. I've never been able to idle at less then 17 afr before. I'll play with the nipple and see what that does.
So am I safe to drive right now? I'm not going to boost at all I just need to get to the test place.
So am I safe to drive right now? I'm not going to boost at all I just need to get to the test place.
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trickster
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07-01-23 04:40 PM