Which Oxygen sensor? 85 Elco [Archive] - El Camino Central Forum : Chevrolet El Camino Forums

: Which Oxygen sensor? 85 Elco


King John
06-29-2009, 03:28 AM
Aloha all,

Now that I have completed my front end build, I am moving onto the O2 sensor as a start because my gas mileage is somewhere in the neighbor hood of 215 miles to a tank of gas. and I get the occasional check engine light. I have located two different types of sensor at the local "checkers" store, they list a "1 Wire; Unheated; Upstream Sensor;" and a "1 Wire; Unheated; Downstream Sensor;"? Not sure if I need the upstream or downstream and of course the guy at the counter didn;t know either.

Lastly, I am pretty sure that this will be the first time the sensor was removed so are there any tips on getting the old unit out? Since I am under the hood anyway, will be replacing the spark plugs, plug wires, distro cap, PCV valve and air filter.

Thanks inadvance.

CoyoteOn2
06-29-2009, 05:07 AM
If 1 O2 Sensor is bad, then the other is likely to be also, or close to it. I would recommend that both be changed. The real Diff. between the two is mainly the hook-up wire length. The best way to change them is with O2 sensor socket, it's slotted. You can use an open end wrench, and may have to use a cheater bar of sorts. It's also easier to do this from under the car. DO NOT use any sealer on the new unit. If you want, you can apply a TINY bit of anti seize to the threads carefully.

BillyJack
06-29-2009, 05:10 AM
I recently replaced mine-'87 305. I used a Bosch upstream sensor. Look at Advance Auto Parts' listings as an example. I don't have any idea why Checkers shows both. Are you showing any trouble codes, or just doing maintenance?
Bill

dougs85
06-29-2009, 08:17 AM
There is only one O2 sensor on an 85 and it's located on the left exhaust manifold.
It would be an upstream sensor.

Doug

CoyoteOn2
06-29-2009, 08:48 AM
What was i thinking? ( My 98 ) My bad. :dontknow: Late night :beer: I guess

King John
06-30-2009, 01:08 AM
Roger

King John
06-30-2009, 01:12 AM
Roger that,

Will be replacing the sensor for maintenance purposes as well as for the intermittent check engine light that I keep getting. Also I have read that if the sensor is going bad or is bad all together it will severly affect the mileage.

Is there a difference in the up stream models as Checker auto has them listed at different prices for the same items. Some show a 50k warranty while the others shos a 30k mileage warranty. Lastly, is that a special socket to get if off as I was thinking since I am replacing the unit, I can just cut off the wire close to the top of the sensor and press the socket down on it.

CoyoteOn2
06-30-2009, 02:56 AM
You can do that John, so long as the Socket is deep enough, and room allows.:nanawrench:

King John
06-30-2009, 10:42 AM
You can do that John, so long as the Socket is deep enough, and room allows.:nanawrench:
Roger that will, definetely make sure I have the socket before I cut of the wires. Since I am replacing all of the listed items, can you think of anything else that may need a little maintenance after 25 years or service? I am not looking for performance, just better gas mileage as I stated before, this car is getting like 220-230 miles to a tank and with gas going back up to $4 soon, would like to drive the car at least sometimes to work (62 miles round trip) withou putting gas every other day.

Thanks again in advance.

CoyoteOn2
06-30-2009, 12:40 PM
One item folks tend to overlook is the Differential Fluid ! Yes, OLD worn out Fluid can and will hinder mileage. I'm sure there are other things you can check / do, but that's just a thought that is often overlooked.
:nanawrench:

escargot
06-30-2009, 12:55 PM
Run the engine untill every thing is warm, it will come out alot easier. JC in Tampa

TRIK-56
06-30-2009, 03:04 PM
One item folks tend to overlook is the Differential Fluid ! Yes, OLD worn out Fluid can and will hinder mileage. I'm sure there are other things you can check / do, but that's just a thought that is often overlooked.
:nanawrench:
I don't mean to disagree with you but thats a new one I've never heard before!

Is this something you've just heard or do you base it on fact that is printed in a manual somewhere? Just curious, like I said thats a new one to me!

King John
06-30-2009, 03:52 PM
One item folks tend to overlook is the Differential Fluid ! Yes, OLD worn out Fluid can and will hinder mileage. I'm sure there are other things you can check / do, but that's just a thought that is often overlooked.
:nanawrench:

Roger that. My neighbor was saying the same thing about when he buys used cars that are more 20 years old. Will make a point to buy the supplies and change it.

CoyoteOn2
06-30-2009, 06:06 PM
I don't mean to disagree with you but thats a new one I've never heard before!

Is this something you've just heard or do you base it on fact that is printed in a manual somewhere? Just curious, like I said thats a new one to me!

I fully understand your question Bobby. Now let's just take a minute and look at it with some common sense. First - What is Gear Lube? Next - What is the purpose of Lubrication?
Answers Condensed
1 - A Substance that provides Protection, Cooling and a Barrier of Friction
2 - To provide all as well as more of the above.

Now the Logic - If one or more of those items are NOT MET, what happens?
Your Protection goes away or down, your cooling goes up or diminishes creating heat, thusly increasing Friction or Drag.
When you are talking HP / Fuel Economy, then does it not make sense that less
Friction, less Drag would be of benefit? In my books it does. But that is just what I think, and heck, what do I know? I change my fluids often, more likely, more often than I need to, and probably more often than most folks do. But it's my Money, my car and that's what I want to do. I really don't mind spending a little now and then for that piece of mind, What I don't like is Spending allot when there is a failure do to my being cheap and just lazy. No one said, and I know I sure didn't say it, "THAT IT'S A MUST DO. It was merely a suggestion, to a question that was asked. If that makes sense to anyone, then they will, or they already do that and maybe more. If it seems as nothing
more than HOG WASH to you or them, well that's OK too. It ain't my Money, or my car for that matter. As a final thought, ask yourself, Why do you change your Oil, just add to it, or Grease your Bearings?
But Hay - What Do I Know? Right?:dontknow:

dougs85
06-30-2009, 09:56 PM
Here- Hear! And some of the newer differential lubes are superior than probably what's in yours. Remember that lube serves the rear wheel bearings also.

Doug

CoyoteOn2
06-30-2009, 11:37 PM
Remember that lube goes the rear wheel bearings also.

Doug

Thanks Doug! I didn't know that!(he he) I learnded me somthig today, always a good day when you lern sumpum. Now ifn I can just remember it.:beer:

BillyJack
07-01-2009, 05:34 AM
KJ,
Have you taken the time yet to check your computer trouble codes? I've been there recently with my '87 305. Multiple codes showing, including oxygen sensor, and baro sensor. The real culprit was the code 21- high TPS voltage. Once replaced, I went from 220 miles to 280 miles/tank, an increase of over 3 mpg. One advantage of the C4 system is that even intermittent codes are stored. Memory is retained for 49 restarts to help diagnose intermittent conditions. Never did replace the oxygen sensor, and now I'm code-free.
Post your codes when you can, and let the accrued experience of the forum members help you out.

Bill

King John
07-04-2009, 08:19 PM
Aloha all,

Hate to keep this thread going but went to Checker to get my K& N Air filter and a fuel filter. The air filter was a no brainer however the fuel fittings are being a real bi-atch to get off. At one point it looked like I was bending the hard line itself so I quickly decided against trying to get the filter out until I get a little more "adult supervision and input" from the forums. Help me out, what does it take to get this filter out withou destroying the hard line? Also, the checker I went to had the tester but it wasn't working right. As soon as I get the codes will post them for you guys to help me with the mileage issue and check engine light.

Aloha and have a great weekend.:nanawrench:

CoyoteOn2
07-05-2009, 04:04 AM
If memory serves me right :dontknow: it requires TWO line wrenches, one on the Hard Line Nut, (flair nut), and one on the filter nut, (part of the filter) And you will have to do this on both sides of the filter. Holding the filter nut, unscrew the line nut from it. If my memory has failed me again, someone will correct it.

King John
07-05-2009, 03:16 PM
Roger that,

Will be off again to get the line wrenches. Have sprayed them with wd40 type stuff so see if I can loosen the grip on the flare nuts. Also, come up with a new issue. Nice puddle of anti-freeze this morning. Find out that my water pump is leaking every so lightly through the weep hole. Oh well, back underneath again. This time will change all the belts and maybe even take a look at the thermosat while I have all the parts out.

Lastly, can't find a single Autoparts store that has a working decoder and the one they have for sale is $230.00...***? It almost seams easier and cheaper to replace the TPS as I have already replaced O2 Sensor, spark plugs, cap & rotor and spark plug wires. Car seams to run much much better but just filled up the tank with 17.5 gallons of gas so I am excited to see what the mileage will be after the tune up. Many have asked am I having problesm with the car and nothing major comes to mine, however I am sure that 12 miles to the gallon is kinda off. All of the parts seam to be really cheap and easy to install so far. Will also be trying the "SeaFoam" as I have heard nothing but good things about it. Will post my results once its out of gas. :)~

:nanawrench:

Bobby78
07-05-2009, 03:36 PM
And sometimes MPG has more to do with how you drive rather than the condition of the car. My wife gets far better mileage on our cars than I do. Well, except on the elky! She says she likes the noise! Flowmaster series 40's on true duels.:dontknow:

King John
07-06-2009, 12:25 AM
Nah, don't think its my driving style. My heavy foot days were over when I got rid of my street/strip VW Bug. No that I have traded "German Iron" for "American Steel", I have 'calmed down'
quite a bit on the road. Not even sure what the "top speed" is on my car as I have never taken it above 65, and that was just merging onto the freeway.

Well, the waterpump went in easy enough, decided to change the upper and lower coolant hoses since I had everything apart anyway. When it came to the thermostat, I noticed two "plugs" so to speak, one I believe is for the tempature gage and the other had two hoses attached to it...well kinda as they looked like they had broken off sometime ago. Matter o fact, the "plug" was broken at the base. Does anyone know what the two connectors on the thermostat neck are for and do I need both of them? If not, I will put a plug in it and cap it off as the car seams to have run fine without it all this time.

Will try to get the thermostat put back in and get the car started after I figure out what that other connection is for.

Will post the details when I figure it out.:nanawrench:

Ted Dubree
11-12-2009, 07:43 PM
I pulled a 9 inch third member and the stuff that came out was thicker tha mapyl syrpil. There was about an inch of thick sludge that wouldn't circulate no matter how hot it got. I don't know how many horses it took to turn that rear gear. Thats the problem with no drain plug.
Ted Dubree

ELBMINO
11-12-2009, 08:03 PM
I fully understand your question Bobby. Now let's just take a minute and look at it with some common sense. First - What is Gear Lube? Next - What is the purpose of Lubrication?
Answers Condensed
1 - A Substance that provides Protection, Cooling and a Barrier of Friction
2 - To provide all as well as more of the above.

Now the Logic - If one or more of those items are NOT MET, what happens?
Your Protection goes away or down, your cooling goes up or diminishes creating heat, thusly increasing Friction or Drag.
When you are talking HP / Fuel Economy, then does it not make sense that less
Friction, less Drag would be of benefit? In my books it does. But that is just what I think, and heck, what do I know? I change my fluids often, more likely, more often than I need to, and probably more often than most folks do. But it's my Money, my car and that's what I want to do. I really don't mind spending a little now and then for that piece of mind, What I don't like is Spending allot when there is a failure do to my being cheap and just lazy. No one said, and I know I sure didn't say it, "THAT IT'S A MUST DO. It was merely a suggestion, to a question that was asked. If that makes sense to anyone, then they will, or they already do that and maybe more. If it seems as nothing
more than HOG WASH to you or them, well that's OK too. It ain't my Money, or my car for that matter. As a final thought, ask yourself, Why do you change your Oil, just add to it, or Grease your Bearings?
But Hay - What Do I Know? Right?:dontknow:


i 2nd this change this out at least every 3-5 yrs..