yeah... I had poor performance and not great fuel economy.. i had some other minor problems as well but I finally pulled an O2 code on the ECU..

Before you finally decide to change the O2s .. make sure that you check/replace the fuel/air filters, distributor cap, rotor, plugs and wires first... it would suck to replace the sensors only to find out that it was faulty plugs....

~Mike~

 

A bad O2 sensor will typically trigger a "check engine" light upon prolonged hard acceleration (going up a long steep hill, for example). Then, when you turn the car off, and start it again, the light will re-set to "off" until you accelerate again. There are more technical tests in the Service Manuals ....

 

Before you finally decide to change the O2s .. make sure that you check/replace the fuel/air filters, distributor cap, rotor, plugs and wires first... it would suck to replace the sensors only to find out that it was faulty plugs....

Yeah i just got plugs, wires, and distributor done this week and its still like this. Im goin to autozone tomorrow so they can put it on the computer to see whats up

 

also too, my car turned off randomly 3 times today while driving. And how much do the censors cost for our cars

 

First i would get new plug wires, air filter, spark plugs and plug wires, dist cap and rotor if they havent been changed on time or dont know when, if you want you can check these things with your eyes and a common ohm tester

a O2 sensor shouldnt make your car vibate or anything, its just a temp sensor that checks exhaust temp so it knows what the air vs fuel ratio is and the computer adjust them as needed. if its bad the worse that will happen is you will burn a little bit more gas than usual and usually lose a unoticable ammount of horse power. your ecu would show a check engine light, bypass the o2 reading and use a preset air/fuel ratio long before it could get so far out of spec it would cause a noticible effect.
basically if the ECU isnt flashing a o2 sensor code and your check engine light isnt on then the sensor is good.

vibration is usually compression related caused by poor spark/ignition, weak fuel pressure, or leaking cylinders. almost every time its the spark or a vacume leak. it could also be engine mounts, but usually that takes a long time to notice. or the ignition timing could be off


i got some questions for you though to figure this thing out
any work done recently?
how long did it take to get this bad? was it over night?
exhaust smells or smoke
in what gears does it vibrate?
is it constant or changing
does it go away at a certain rpm?
is it while driving or parked?
any puttering?
is it worse with the engine hot or cold?
Hissing or clicking sounds comming from the engine and where?
btw, fuel injectors are supposed to click, but one clicking alot louder than the rest or not clicking at all is a problem. drive belts can also sound like a hissing somtimes and arent a problem.

if you can give some good detail i can probably tell you exactly what it is and how to fix it.

 

if you've done all of the plugs wires and cap and rotor...and it still shakes you have a problem

don't take it to autozone because you can see if you have the codes your self.

you can check to see if your o2 sensor is bad by hooking up a dvom.

what kind of spark plugs did you get??

and i see your located in chicago....

 

i got some questions for you though to figure this thing out

within the week i got the plugs, wires,and distributor cap put in, this problem started about a week or two before this was done. There are no smells and it shakes in park, drive, and a whole lot in reverse. doesnt seem to matter if the car is cold or hot. when i accelerate to a higher speed i hear a pop pop pop.

 

and i see your located in chicago....

Yeah i live in the wicker park/ humbolt park area. The plugs i got are Denso, and the wires i got were Advan-tech, I asked the guy at Maverich autoparts for the stuff for a tuneup and this is what he gave me, he said the stuff would be good. I really appreciate ur guys help with this too

 

within the week i got the plugs, wires,and distributor cap put in, this problem started about a week or two before this was done. There are no smells and it shakes in park, drive, and a whole lot in reverse. doesnt seem to matter if the car is cold or hot. when i accelerate to a higher speed i hear a pop pop pop.

It sounds like you just needed a full tune-up chitownlegend... replace fuel/air filters as previously suggested, pcv valve is important as well and also add some fuel injector cleaner in your gas tank on your next gas fill up.

 

the poping sound, is that comming from the exhaust? how loud is it? could be back firing or sputtering indicating is is a timing or ignition problem.

did you make sure you have no vaccume leaks? that will can cause those symptoms as well as the ignition. are your rpms stready in park, does your tach sit still or bob or drop?

also pull one plug wire at a time and see if any dont make a sigificant change, that could indicate a poor spark to a single cylinder throwing off weight balance and power loss. just dont pull it more than 75% out the plug hole or you can be shocked.

 

the poping sound, is that comming from the exhaust? how loud is it? could be back firing or sputtering indicating is is a timing or ignition problem.

Actually the popping sound is coming from the front of the car. today i put the fuel injector cleaner in and i noticed a bit o a difference but is still shaking. Could it be that i need a new fuel filter?

And the rpms are steady, the popping sound, sounds like its coming from the front driver side, idk possibly around the air filter

 

while the car is running in park pull the accelerator cable under the hood to make it rev up and see if you can pin point exactly where that popping is comming from.

 

while the car is running in park pull the accelerator cable under the hood to make it rev up and see if you can pin point exactly where that popping is comming from.

tried that and i guess it only does it when i drive the car. UPDATE: the car is even worse now than when i first posted, ive done nothing different and now there is a sound coming from the muffler, idk if its backfiring, it just sounds like its underwater or something. And the worst part is that i filled my tank up yesterday and today i only have a quarter of a tank or so. it ate up all my gas. I have no idea what is goin on now.

 

hmmm check to see if the dizzy is sparking.
if it sounds like that aparntly shes running rich...or just dumping fuel in the cylinders.
may sound crazy but in order to get it to burn fuel properly it needs air and spark.
remove the air cleaner and then see how it runs also.

odd are it's prbably something simple ...yet stupid.lol.

 

its kinda odd that theres no smell or smoke if your running that rich.
is there any soot around your trunk or bumper or more than usual at the tail pipe?

you checked your ECU for any blinking right? somtimes the check engine light will go bad.

Theres so many things that could be wrong with your car right now its not even funny, most of these things should show a check engine light though

you should pull your spark plugs and see what the electrodes look like, any electrode wear, any look different from the rest?

 

the ends of the first 3 plugs in front were black, should i get different plugs, maybe NGk, thats what were in there before and i had no problems

 

touch the electrodes and make sure its soot and not just black electrode metal. soot confirms the obvious, your running rich. they are just black from soot and the electrode is good through right? not rounded off on the edges or missing pieces right?

the 3 on one head are black, but what about the other head, did you not check those? its kinda funny if just one head had black electrodes. If thats the case it could mean some of these things

leaking valves on every cylinder on that head
air flow being restricted only to that head or extra air flow to the other head (very unlikley)

ive never seen just one head be effected so i wouldnt know what to tell you about that. Ive seen one cylinder be effected, but not all 3 just happening just to one head so im wondering if you checked all of them

if all of them are black you need to check the following things
Ignition coil
Plug wires
Spark plugs
old or clogged Air filter
blocked airway
Ignition timing
Injector resistor
fuel injectors.. kinda hard for all those to go bad at once though...

If all 6 plugs are black I think your spark is off time or missing sparks or putting out weak sparks to be losing all that power while burning that much fuel. when this happens your fuel will be blown straight out the tail pipe not being burned

So you got new plugs, wires and distrubutor cap, thats all right?
you should look at the rotor inside the dist and check it for play. also replace that air filter.. both of these should be under 20$

 

also replace that air filter.. both of these should be under 20$

The air filter was changed about a month or two ago, way before any of this started goin on. and what about my fuel filter, is that not an issue at all, i just bought one just in case, when i put it on, ill post if there is a difference

 

usually a clogged fuel filter will kill your highend really bad, the harder you press the gas the worse it will get, usually has some pretty serious symptoms.

if it hasnt been replaced in a long time its probably a good idea to replace it anyway.

If your running high octane fuel you should maybe try switching to a lower that way its easier for a weak spark to ignite just incase.

 

OK dude....seriously have you checked you ECU to make sure its not throwing codes? And a way to check that your CEL works is when you turn the ignition key to "Start" and the dash lights do the systems check, that light should come on and then shut off after a couple seconds...

A lazy or malfunctioning O2 sensor could possibly cause some of the symptoms that you are describing...I say go ahead and change em out and see where that gets you...I have seen an O2 sensor malfunction before enough to affect perfomance, but still not go outside of the ECU's allowed parameters therefore not triggering a CEL....just something to think about!

Also wouldnt hurt anything to do new NGK plugs as well (get the $1.99 copper ones)...ALSO youre absolutely sure that you dont have two spark plug wires crossed right (stupid question but one i think is worth asking!!) ??

 

^ damn why did'nt i think of that.
when i adjusted the valves i crossed two of the wires.....
i thought i messed with the valve timing way off.

 

Today i checked all of the spark plugs and all of them had black stuff on them and i was able to wipe most of it away, i then checked my muffler and it had some simular black stuff also, im guessing its soot. When i checked the ECU today it wasnt throwing any codes. As for the wires being switched that could be a possibility, but how would i correctly fix that I dont wanna mess anything else up with the wires

 

Today i checked all of the spark plugs and all of them had black stuff on them and i was able to wipe most of it away, i then checked my muffler and it had some simular black stuff also, im guessing its soot. When i checked the ECU today it wasnt throwing any codes. As for the wires being switched that could be a possibility, but how would i correctly fix that I dont wanna mess anything else up with the wires

Sticky'd... Auto Zone - G1 Engine Diagrams, thread started by sciarhir! follow the links and you'll find some (but not all) useful tips and informations... hope this helps

 

Is your distributor cap numbered? If so, follow each wire and be sure that it is going to its correcsponding cylinder:

(CYLINDER's 1 and 4 are on the Timing Belt side)

FIREWALL
___________
1 2 3

4 5 6
___________
RADIATOR


Here's how the cap is layed out (looking at the top of the cap while mounted on dizzy)

Top
2___4___1
___________Coil Wire on right side of cap
5___3___6
Bottom

Hope it makes sense cause i dont have my digi cam with me right now

 

Man u guys are sooo helpful, i thank all of u. Instead of me lookin for the obvious i right away thought of the worst. i went on the autozone site like someone suggested on here cause sam o nela brought up crossed wires, i looked up the chart, i took off all the wires off the distributor cap and redid them, turned on the car and it works like new. lol i feel soooo embarresed, now u all can make fun of me, thanks for the help tho i really appreciated it