2000 alero 2.4l o2 sensor.

can anyone help me with some basic instructions on location and replacement of the o2 sensor before the cat.

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?partName=Engine+Performance +%26+Emission+Controls&pageId=0900c1528023b042&partId=0900c1528023b042

ok i installed the new o2 sensor and new plugs and plug boots while i was at it. now i have a problem. the car runs great under acceleration, but when it idles in park the rpms slowly drop from 750 to 500 then 500 to 400 then it will surge almost like its trying to recover and not stall. fuel filters new, injectors are good. any idea?

also this new problem came with a generic p0300 code.

P0300


Random/Multiple Cylinder Misfire Detected

you did something wrong w/ the r & r job of the plug wires and/or spark plugs

or maybe a bad plug wire from the box/ incorrect gap of the plug

pull em out & check resistance of the plug wires & gap of the plugs... <shrugs>

dude!

just post the link, not the whole article!

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as for the OP, he had the code come up AFTER he changed his plug wires and plugs... so that may be the contributing factor

Sorry Guy,
The last few Links that I posted did'nt seem to get read and everybody is looking for the "quick fix" without reading.
I'll be more compliant in the future.
My bad!

ok so i pulled the plugs and boots again and checked them out at autozone, they test fine. the tech at autozone reffered me to a guy at carquest who checked the engine specific computer model and said the plugs i should be using are 41-942 however he didnt carry them and the guy at autozone swore up and down that the 41-963 plugs that i have are the correct ones. there seems to be no other problem with the coil pack or the boot insulator. im im sure .08 of a gap wouldnt make this huge of diference. im stumped.:banghead:
i WAS thinking the mass air flow sensor could be the problem but im convinced its plug related due to the fact that it ran perfect untill i installed new plugs and boots...started it up and the rpms dropped to 400 surge to 1000...repeat. and its only while stopped or idling. and gets worse the longer it runs. logicly it can only be so many things. im out of ideas.

yea, did you do a trouble code scan before? is that why u changed out the 02 sensor to begin with?

that number is correct since it's the platinum version...

trouble code scan again to see what other possible problems & clear it to see if same #s return...

i guessed u already check the physical mechanics as well i.e. vaccuum leaks & such

fuel filter is ok as well? :runaround:

----------------------------
& toddman, i got spanked for doing something similar in the past...

this is what you should do w/out getting in trouble w/ the mods & legalities:

http://www.engine-light-help.com/P0300-check-engine-light.html

that's a nice reference site by the way todd; i'm bookmarking that... thank u!

yes fuel filter is new as well. there was no trouble code before this all started with just adding new plugs just to keep it maintained believe it or not lol. directly after the plug and boot change came the code, auto i suspected the new plugs or fuel filter may be pushing one of the o2 sensors over the edge. so to cover the bases i replaced them both as there are 2 in this car. the code remained. the first time i drove it more than 15 minutes instantly the car was junk. it bucks horribly under acceleration, and surges to keep from stalling when its idle. i removed the icv to clean it up but there was not a spec of corrosion on it :eek7:.
the code never gives a cylinder numder either its always the generic 0300.i have cleared it several times and as soon as you start the car it comes up again. im losing my patients with this car lol.

Check major vacuum leaks for sure! Especially brake booster hose, and other major lines, make sure the o2 sensor was done correctly, wires and part number. Listen carefully for leaks, sometimes a hose rubs somewhere and the leak gets worse and worse and its hard to see because its sitting on another part where its wearing through.