93LX5.0L5SpdConv

Since I plugged the BIG vac leak in the intake manifold I've been running 16psi vacuum (which is a bit low isn't it?).

Recently the CEL came on so I checked the codes - 41. I thought it was odd to have just 41 w/o 91, so maybe still vac leak. I swapped them to the other sides, after cleaning each with carb cleaner (I also burned them with plumber's torch) and cleaning the contacts with MAF cleaner and reassembled both with dielectric grease on the contacts.

Of course that threw (I reset the computer at each step) both codes 41 and 91 - and I went from 20mpg on tank to 15.8, almost all of both were taking it real easy on the highway in O/D.

Today I built a better smoke tester and found another small leak where the charcoal canister plugs into the manifold. Addressed it, no noticeable change in the vac reading - still 16. I also saw smoke that looked like it was coming from the top of the TPS, or maybe the EGR, but that was inconsistent so it may have snuck over from elsewhere, and of course eventually the intake filter in the fenderwell.

Hooked up the battery, drove it for 15 minutes, just enough for the CEL to come back on - now it's showing me KOEO codes 11o, 91c, 41c, 1c, 10 and 30. I know that 11 and 10 are pass and spacer codes, but WTF is 30?!? BTW, the air bag idiot light has been on, with varying patterns of flashing, most recently just staying lit, for at least several months now.

Before I throw $100 I don't have at O2 sensors I probably don't (I put these in at some point, and I've had the car for just over 10 years and 100k now) need, what am I missing? Did any (all...) of my O2 cleaning tactics cause or worsen the problem?

Thanks

mjr46

you don't clean o2's if that's what you mean, if no vac leaks exist and maf is clean and good, replace o2's and retest

93LX5.0L5SpdConv

They didn't even look like they needed cleaning, both are almost uniformly white. Could I have damaged them cleaning them like that?
Is 16 vacuum way low or OK?

mjr46

like i said you don't clean o2's nor contaminate them with any type of liquid that is silicone based or has such in it and 16-19 depending on engine worthiness is fine for a 302 as long as no vac leaks are present, make sure o2 ground on back of head is still attached

93LX5.0L5SpdConv

Thanks MJR, I'm glad to know there's a ground to check before I throw $ at parts.
I took apart and wiped some of the excess dielectric grease off (that I put on) the connectors, then got just a code 91. The CEL consistently takes at least a good 10 minutes, well after it's warmed up, to come on whether I've just rest the computer or not.
The last reset and 20 minute drive didn't blow a code at all. I'm thinking this is a pin or ground connection issue, some of the pins were a bit greenish when I swapped the O2's side to side.