Is O2 sensor life short with FI application? Please, what is your experience? Is it wise to replace both, or, just one?(Replaced left bank twice in 3 years and just had another failure. App... ATI D1 15psi 383 LT1 modified engine.)

 

how do u figure they are dead?

 

No output from the afr gage when switched to left side. Rt sensor shows variable voltage activity. Usually when the sensor fails, there is zero output. The engine left bank #1 will not fuel correctly (low afr). I'm thinking heat is shortening the life of the left sensor. Maybe move it down stream in exhaust will help it live longer.

 

where are they located right now? O2 sensors are designed for high heat. are you running leaded race gas?

 

Denso o2 FTW

 

Leaded gas makes O2s die fast. A friend of mine killed both of his O2s recently with one night at the track running leaded 100 octane.

-Pete-

 

Not running leaded gas (93 with methanol/ h2o + intercooler). Good thing I got the auto-meter afr gage. Tells you if sensor has output. Guess there is some value having it. Changed sensor out, and, now there is activity identical to right side. I think It's too hot up there near the cylinder head on #7. A real pain to get @. Checked the plug and a good color. I have good success with the Zex plug (does not fowl as east as TR6 ngk). I have short headers (sensor in stock location). I think a long tube and O2 sensor placement would live longer (Sensor... gm Bosch type #15703). I tried a Denso before, but, it broke in less time. This winter I will change location of the sensor. Thanx for all your thoughts and support. B.

 

I'm running JBA shorty headers with the O2 sensors in near stock locations and never had a issue with premature failure of O2 sensors (AC Delco). I look at my O2 sensor signals all the time as I have a Scanmaster.

 

how close to the cylinder head do you have it?

 

Cannot remove #7 plug without removing O2 sensor. That is close. It does get hot in that area under hood, but, I have a large hood open to free air flow when moving. ANother reason for moving the O2 is #7 plug access. The slp short headers do offer good maintenance access (ground cleance also) to alot in that Motor Compartment area.

 

why would you put it that close to the cylinder? that very well could be the problem. move it to the collector where it belongs.

 

That is the design of the slp short header (O2 close to head). Their design criteria was a replacement for stock manifold. It is close to the identical location of the stock O2 manifold. I will eventually move it (weld a 2nd bung on the down pipe bank#1). Back in the day (1998) there were not many header systems available. Also, the amount of air (ATI DI) and fuel (from 72# injectors) probably adds more heat than NA. I got alot of cash in the exhaust system now, and, have been putting off long tubes. I've got alot of mods and would like to do another car project (something with lots of space). I do like the "Stainless Works" tubes for the LT1. B.

 

gotcha. I'm not familiar with the SLP headers so I wasn't aware thats how they are made.

 

Yes, just lost another Bosch sensor (bank#1/ sensor#1) on the left side. New sensor I had (maybe 2 years old). Do these things have a shelf life??? Anyway, I saw the output go intermittant and then zero (lean) today. Just made it home. Possibly the D1 is to hot for this sensor??? My only option is to move it down stream in the exhaust. Car will not run @ all without it. Thanx for any comments and suggestions. (97ss 383 - D1) B.

 

Maybe it was coated? Those stainless headers if coated the coating will flick off, if you had yours coated inside and out than maybe the aluminized coating is getting into the sensor LOL