Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Well, that's a ray of hope. I saw that it remained in alcohol content learning mode for around 7-8 miles last time I was monitoring and it settled fairly accurately. This time it was learning for only 2, maybe 3 then stopped and with the content at 56%, just as it was before. I drove about 80 miles today but wasn't monitoring. I wanna spend some time tomorrow troubleshooting that speed sensor issue. If I can manage that, I'll pull another fuel sample.
Do you know if the PCM responds quicker and learns sooner with the physical sensor?
I used Denso 234-4668 (which I now see also shows up as "Denso 12594452" ). I thought Denso provided sensors for AC Delco and, therefore, were OEM. Would the physical sensor remove the O2 sensors from the equation for calculating alcohol content?
It probably isn’t a coincidence and the sensors I took out were different in appearance from the ones I put in. I chalked it up to a design change or something. I just raised the point that many of us are running the denso sensors. Had I even had a suspicion they wouldn’t be as good as originals I would have spent the $$. We were all under the impression they were good.
Yes, the physical sensor calculates the AC% near instantaneously but do not remember if it later "spot checks". I learned this from a guy over at Silverado/Sierra who installed the sensor on his 900 pickup.
Chris, that sensor part number is not for our motors. 12583804/213-3866 for Downstream and 12609457/213-4229 for Upstream.
On the "smart page" for the sensors on the ACDelco website is an interchange list. 10 different numbers are listed for other manufacturers but I do not know if they would throw off the alcohol content or not. Never got that far to record part numbers of the sensors that caused problems.
View attachment 396420
I know George. This is a recently revelation after years of discussing this.
Thank God it did.Surprised the cap was able to hold the pressure in