I been running 100oct for 5 times in a row until recenlty my car doesnt drive as fastmore. The gas is 100unleaded and I also changed the splark plugs to BR8ES and the idle is uncomfortable without ac turned on. Based on this, are the injectors fooked? or the o2 sensors?

 

Might be the gap on the spark plugs. I noticed a loss in performance when I replaced my stock plugs with some aftermarket ones and also spark them to the wrong specs. I fixed the gap but the car still feels slower than before....

 

Yea Im going to have some BPR7EIX and see whats up tomorrow then.

 

It depends on how much power you are making. Unless you need to 8 series plugs, they will hurt performance.

Put the 7 series plugs in at stock gap and see how it is then

 

Do a boost leak test

 

If you haven't already, don't buy those yet. Buy a set of BPR7ES copper NGKs, because they're only $1.40 each. You can gap those to .025, slap 'em in, and see how they work. If they do work, then you can decide if you want to put in BPR7EIX (expensive iridium that lasts longer) for the longer term.

My experience is that the BPR8ES work for me when on 116oct and 24-25psi at the drag strip in full out drag mode, but then when tuned back down to 93oct and 21psi, they don't work well at all, so I put my stock 7 series iridiums back in for daily driving...

 

im having the same problem with about 3 full tanks of 110 , you guys think the o2 sensor is shot ?

 

You might just be use to the power from 110

 

Three things.

1. You sound like you may have a boost leak.
2. If it is truely unleaded it won't affect the O2 sensor.
3. What is your engine management consist of?
If it is stock ECU only then the 100 is your learned fuel after so many tanks. If you dropped back down to 93 then the ecu is possibly pulling timing because it needs to relearn the fuel. Try reseting the ECU.