O2 sensor or possibly bad gas?

[Aron]

As most of you know, my car has been sitting since October with a broken trans. That is the last time I put gas in it that I remember. I also replaced the left O2 sensor around that time, due to a misfire/SES. Car drove fine after that.

The trans is now repaired and while driving home from the shop I noticed it has a misfire and the SES came back on. There was about 1/4 tank of fuel, and I thought maybe it was bad, so I stopped and put $20 of Shell Premium in (approx. 7 gallons). Still misfiring. Checked the SES and it's the left O2 sensor again - "DTC 44, left O2 sensor lean condition". I haven't had a chance to look at it yet.

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[sideways]

i had bad gas once








and then i took a shit

 

[wolfe]

Opti spark FTL, or it's just a bad O2, take it back

 

[Aron]

99% sure I found my problem. I'll post later

 

[Aron]

Ok, so here's the deal. I was doing some thinking yesterday and it occurred to me that besides the misdirected, the new trans was shifting extremely hard. So I checked the line for the vacuum modulator for the trans, and it was disconnected, causing a huge vacuum leak. I plugged the leak with a bolt and took the car.back to Hans. There was still a minor misire, so I datalogged the drive there and found that the oxygen sensor on the left side (the new one) was lazy, so it went bad already. I found an awesome deal on a new one on Amazon.com so it should be here next week.

Anyway, Hans found that the vacuum line had slipped off and the end was a little loose so he made me up a new line and threw it on.

I can't wait to get this thing running right so I can see how it runs with the new converter.

Big thanks to Hans for helping me out on short notice.

 

[wolfe]

You should still blame the optispark, as an LT1 owner that is your responsibility. Everything wrong with the car is the optispark.

 

[Aron]

You should still blame the optispark, as an LT1 owner that is your responsibility. Everything wrong with the car is the optispark.

Actually I've never had any problems with optis. I replaced the original stock one somewhere around 200k as preventative maintenance when I was installing the headers and electric water pump. Never had as much as a hiccup. I put another GM one on, for about 30k. When I put the new engine in, I had to upgrade to the newer vented style opti because of the cam. I didn't want to spend a fortune on a new one, but I just happened to have a filthy, nasty looking one that I got in a crate of parts from a kid I bought an engine from. Cleaned it up the best I could and threw it on. It worked fine and is still on the car 3 years later now.

 

[wolfe]

Damn, that's impressive. I hope it continues to treat you well.