Hi,
I'm still trying to figure out why my 84 is stalling and sputting when driving. (see this thread for my first post)This Thread

So far I've changed out the cap/rotor (no difference)
changed out the plugs/wires (no difference)
checked vacume lines, while the car is running and I don't see any leaking or collasping on themselves.

I've been doing some searching on the forum, and thought maybe the 02 sensor or maybe if the cat is clogged. I took the sensor out, and drove it around, and it acted the same. Just no power at all.

Before I put the 02 sensor back in, I thought I would take a picture of it, and see if any of you can tell by looking at. If there are some signs of something else to check?


Thanks
Chris.

 

thats the bad thing about O2 sensors they can be brand new and still go out shortly after installing them.

 

this ones a couple years old, should I just replace it?

Is there a way to test it, to make sure it's bad? before spending another $30 on a part that won't fix it

Or something else I can do to make the car think it's working the way it needs too? Just to see if it makes a difference?

 

i dont think there is anyway to test te o2 itself... wish i could help you more. ive had o2 sensors go out, and i bought a new one and it go out. so ihad to buy another one. sorry, i couldnt help you more

 

The whitish color on the sensor indicates the car is running lean (if it was rich it would have a black sooty deposit). Try unplugging the M/C solenoid connector and take it for a short drive. If the problem clears up you've narrowed it down to a bad O2 sensor, M/C solenoid or an ECM problem.

 

The only way to test an O2 sensor is with a Digital Lab Scope. They graph live voltage data and for a cheap one you're looking at ~$1000. I doubt it will fix your problem, but you might want to spend the $30 to replace it anyway...

 

Ya I don't think it's that either, but I wasn't sure if you could tell something on how the car is running by how it looks. Like a sparkplug, by the color ect.

So I thought I would post the pic, just to see.

Is there any kind of test I can do to see if the choke is working right? I've had so many problems with it in the past, I jsut have that feeling it's the choke again.

I've tested and it's getting the 12v likes it's suppose too, but just not sure if it's actually opening/closing lilke it's suppose too.

 

When I got my 84 Camaro the O2 sensor was blown out... the hex part was still screwed in the manifold, the element and the wire were still plugged into the harness dragging under the car. It ran just fine that way. I'd say that that O2 sensor is not causing your problems.

 

I looked over the other thread, and to be honest I don't think that any of the normal tune up stuff is going to cause the kind of problems you're having.

Vacuum lines, and the O2 sensor aren't going to make much difference to a carbed 2.8.

It sounds like your problem only occurs when the engine is under load? yes? no? Is it only when the car is hot?

I'd be looking at the fuel pump, fuel lines, filter, carb, and then at the ignition system starting with the module or distributor.

Bad tune (crusty distributor cap/rotor, slightly melted plug wires, etc) won't make for the problems you're having till they're really really bad.

To isolate the choke, unplug it and if need be wire it open.

 

It seems to do it either if it's cold or hot.
Searching the forum, I'm thinking maybe the fuel pump or clogged filter.

So going to replace the filter first, and if it isn't that. I'll have to check the pump. I need to get this fixed because it's due for emissions in a couple months (it will fail, it always fails) but I need to at least get it there

 

Current thinking on the O2 sensor is that they are not changed as part of any preventive maintance. It's not a tuneup part. Change them out when they fail. Mine's been in since the car was built.

 

How do you know when it's failed??? Remember, our cars only set a light when the circuit goes Open, shorted, or grounded, that's the only time we get an actaul O2 sensor code. YOu could have a lazy O2 and be running mostly rich or mostley lean all the time and never know it. Our computers are STUPID. They don't tell you when an O2 is bad.

They are supposed to be changed every 30,000 MI.

 

If your running mostly rich or lean, then you will have numerous other driveability/emission issues that would possibly point to a bad O2 sensor, or numerous other problems. No computer on any car "tells" you anything, and I never said that it did. All it does in the best case senario, is indicate which part of the diagnostic chart in the factory service manual to check. As far as O2 sensors are concerned, GM originally advised changing out the sensors every 30,000 miles. That was the thinking 20 years ago. As dealers and other technicians began to notice that they were lasting much longer than 30,000 miles, this service directive was largely dropped. Another point to make is that many people have changed out good O2 sensors for defective ones, and many aftermarket O2 sensors, (Pep boy specials), are designed to "sort of work" on a dozen different cars, but may not be entirely within the operating perameters of a 2.8 MPFI emission system from the 1980's. Bottom line, if you do change your O2 sensor, get the correct dealer part.