[ddarkslayer]

okay so today I got a check engine light pop in my dash on my way to a friends house. I parked my car and ran a KOER test and only got code 41

heres the breakdown: new fuel filter, 11 month old BBK walbro 255 lph fuel pump, new ECT, new EGR, new O2 sensors by bosch, new purge solonoid. I'm running an offroad x-pipe and 24 pound injectors with a calibrated 73 mm MAF. manifold pressure is at -20 at idle, timing is at 12 degrees running 91 octane. fuel pressure is unknown (I don't have a fuel pressure tester.)

what do you guys think? I was starting to climb a hill when the MIL lite.

[ddarkslayer]

anyone?

[fogged306]

Swap o2 sensors from drivers to passengers. If you get a code 91 then your o2 is shot. If you get the same code then you have something wrong with your connector or your wiring.

You can also try heating the tip of the o2 with a propane torch to see if you can bring it back to life (if you determine that it's bad). Sometimes running rich will coat the o2 with fuel deposits and it won't function anymore.

[ddarkslayer]

Originally Posted by fogged306 Swap o2 sensors from drivers to passengers. If you get a code 91 then your o2 is shot. If you get the same code then you have something wrong with your connector or your wiring. You can also try heating the tip of the o2 with a propane torch to see if you can bring it back to life (if you determine that it's bad). Sometimes running rich will coat the o2 with fuel deposits and it won't function anymore.

thanks fogged. strangely the code just randomly went away

[fogged306]

That's usually a sign of the o2 on it's way out from what I've experienced. They sometimes don't just die instantly, they'll throw an intermittent code for a while before they fail completely. If it pops back on there's a good chance the o2 is bad.

[ddarkslayer]

I bought bosch O2 sensors. I only hear there sparkplugs are pretty bad, but whats there rep on there O2 sensors?

[ddarkslayer]

I only had there O2 sensors for 6 months

[WickedSnake00]

Here's the way to test oxygen sensors. You'll need a propane torch, DVM, and basic hand tools for removal.

Of course when you remove it you will want to look at the coloration of the tip. Lead, excess carbon, and even antifreeze can contaminate and poison the sensors.

Remove the O2 sensor. Clip the leads of the DVM to the correct leads of the sensor that read oxygen content. I've only done this for 4-pin heated ones, and I don't know if your model has a heating element in it. Bottom line get a wiring diagram and connect to the actual sensor circuit.

With the sensor in the atmosphere, you should be reading 0 volts, which translates to completely lean. Light your torch. Put the sensor tip in the flame. This simulates a completely rich environment, as all oxygen is consumed by combustion. Your DVM reading should quickly spike to 0.9-1V. If it takes an extended time, over a minute or so, or doesn't achieve 0.9V, it's bad and needs to be replaced. Remove it from the flame and it should rapidly return to below 0.1V. If it fails this, it is a bad sensor.

I hope this helps. It's a cheap and easy way to prevent yourself from going out and buying an expensive sensor for no reason.

[ddarkslayer]

hey thanks man I'ma try that.