ssheets

iTrader: (1)

I got a 135 and a 155 DTC this morning which is both O2 sensors...what could cause both of them to go out all of the sudden? Maybe this is why my car is having problems with the tune?
I have another set of O2s on the bench, what can I use to clean them without hurting them?

Will running real rich foul them out?

The ones I took out are black and full of soot.

wait4me

iTrader: (10)

They where probably killed when you had your MAJOR vacum leak and drove it around for so long while it was leaking that fresh air. In response to that, the engine sees that fresh air and starts dumping in alot more fuel in order to fix a "lean condition" that did not really exsist..

ssheets

iTrader: (1)

The problem is, I wasn't driving on those sensors. I changed them out after I found the vacuum leak as you recall, I called you to tell that it was running great after I had torqued down the throttle body and only had a question about slightly different LTFTs under transitory conditions. After that I swapped the O2s and it was running perfect for about a week and then all of the sudden it went back to high idle and a few days later I got one code and then about another day I got the second code.

So will running rich take out the O2s? If the just soot up can you clean them? If so, with what?

I drove it a little bit today (back to the factory PCM with Predator tune) and watched the mv signals and both sides seemed to be responding to changes fairly evenly and quickly. I wish I had a better scanner to read and log parameters.

Well it ran great for a week and now it's snowing...I'll swap the O2s when I get a chance. I don't feel like crawling on my back for now though. Looks like a lot of people clean them with electrical cleaner and some heat. I'll give it a try on the ones I pull out. The 135 and 155DTC are for the test on startup. I believe it is set if the sensor fails to bias the mV signal within a predetermined time, two startups in a row. If they're sooted up it may be attenuating their ability to read and change as quickly as they should, but it wouldn't hurt the actual TC junction.

ssheets

iTrader: (1)

I drove it to the office today...about 6 miles each way. I'm still on a reset of the DTC codes, but it runs strong on the factory PCM with the predator tune. It may be a tad rich and has a little bit of an issue with hot re-starts, but the LTFTs are between 0 and 2.

I may swap back to the W4Me PCM and see how it goes. The two PCMs run about the same, but the W4Me tune is better at the hot re-starts and has the random misfires programmed out.

Viper

iTrader: (6)

" If the just soot up can you clean them? If so, with what?"

Use a $10 propane torch from Lowes, put the O2 sensor in a vice and hit 4 sides with the torch for about 30-60 seconds. Cleans them right up.

ssheets

iTrader: (1)

I'll give it a try, I have an extra set on the bench. Although these haven't had any failure codes, but they are the ones that sooted up. I haven't looked at the ones that are popping the 135-155 codes.