Thread: Should I replace oxygen sensor?

I'd say leave it, if its running good.

Did you use stock replacement plugs (ac delco)

Well since you've gone this far, lets do 2 more things.

Take the throttle body off and clean it, along with clean the maf with maf cleaner, youd be suprised how dirty both get in a short time.

Also if you have not changed the trans fluid yet, I suggest you do it. NO FLUSH, just buy a filter and 8 quarts of dexron 3 and do a pan drop. Its a good idea to do it now, because the fluid is old.

Correct, just take the maf out and spray it down.

I suggest dexron 3 because thats what was in it from the factory, dexron 6 came standard in mid 05 I think. If someone really wanted to you can put 6 in no problem because its interchangable.

But I just like to put exactly what came in it from the factory, because thats just me, and dexron 3 is about 1-2 bucks cheaper per quart.

The stock trans pan gasket is metal, clean pan/trans surface and metal gasket and just re-use it.

Get 8 quarts of fluid because a standard pan drop will take anywhere from 7-8 normally. I would start with 6.5ish and do the proper fluid level checking (trans hot and running) and add as needed.

Also those wires you bought are fine.

Originally Posted by GrandprixSteve

Oh yeah - thanks for the MAF suggestion. I saw some MAF cleaner at O'Reilly's the other day and wondered if it was worth anything. So just spray it on the screen-like element in the intake?

No, you'll wanna use the straw to direct the spray on the tiny little wire elements going across the center of the MAF.. I always thought it was easier to get it from the open side rather than the screen side. Soak it good and make sure it is 110% dry before you reconnect any wires. Take the MAF and throttle body off the car all together to clean them, so much easier.

That way you'll be able to get the TB with TB cleaner from both sides, and use a cloth to wipe down the plate and insides of the passage...

The MAF works by heating that wire to a very specific temp, the pcm monitors exactly how much power it takes to keep the wire at that temp as air flows over it and cools it, and that combined with the IAT input and the defined volume of the tubing is how the computer knows how much air is coming through the intake, so when crud gets on it over time, it can seriously change the MAF readings. That's also why you DO NOT want to touch those little wires with ANYTHING... only spray them and let them air dry.

I also got a long tire cleaner and wrapped some paper towels around it, soaked it in tb cleaner and used it to wipe clean inside the plenum opening as far in as I could get.

Got the MAF and TB cleaned this morning. Although I cleaned it good in the fall, the TB was very dirty but not cooked on like it was before. A little Seafoam and it came up quickly. I cleaned about 3-4 inches into the plenum, too, as far as my hand would go. MAF was straight forward. Idles very nicely now - probably result of TB.

Will I notice any driveability difference after cleaning the MAF or is it just an MPG thing? Also, I've heard it takes the PCM a certain amount of time/driving to recalibrate to new/clean sensors. Any knowledge on how the PCM responds to this sort of maintenance? Just curious.

As for the trans pan drop. I have a couple of questions.

1. Went to Oreillys this morning and they have Valvoline Mercon which says it is Dex 3 compatible - I didn't see anything that was specifically Dex 3 - so is Mercon what I'm looking for if I'm sticking with Dex 3. You were right FFDP - it's a couple bucks a qt cheaper. About 20 bucks a gallon vs 30 for dex 6. Here's a link to what I was looking at http://www.oreillyauto.com/site/c/de...0471&ppt=C0207
2. Also a question about trans filter. They have a Wic for 18 bucks. I know Wic makes good oil filters but they're not relatively cheap. However, the AC Delco is about 50 bucks. So does Wic make the same quality trans filters as it does oil filters? Whatever, what I'm asking is which should I buy given the difference is almost 3X?

At napa it says on the bottle dex/merc I believe, so valvoline mercon is the same thing at oreillys.

And I always just use the wix filter, I think my cost at napa is 15ish bucks, so 18 sounds about right.