86 3.2 02 Sensor
 

My new to me 86 Targa had its 02 sensor replaced back in 2000 (13yrs old now) and it has about 8k miles on it presently. I have driven the car about 100 miles since I got it about a month ago and she runs great. Idle is ok but when I take the gas cap off she starts to break up a bit and I’m thinking this could ne the 13 year old O2 sensor.

What is the useable life on these? Should it be swapped out now or should I wait until I install the MK pre-muffler in the up coming warmer weather?

Appreciate your thoughts.
Vin

Vin,

It is normal for your idle to "rumble" a bit when you remove the cap on your 3.2, because you are introducing vacuum to these engines when you do so....it has nothing to do with your O2 sensor.

I've noticed that you have another thread in which you are attempting to locate your Idle Control Valve as well. It seems you are doing your homework in an attempt to improve your idling condition. Good for you!!!

Yes, a faulty O2 sensor or an dirty old ICV can certainly be the culprit for a crappy idle and should probably be the first things to look at when hunting down a poor idle condition. Check all the cheap and easy stuff first. Sometimes, readjusting your base idle at the throttle body has remedied this problem. Othertimes, most of us have had the displeasure of hunting down dreaded vacuum leaks, which is most often the cause of idle issues.

That being said, have you picked up a Bentley manual for your ride? Highly recommended if you have not done so yet.

It sounds like your problem is probably minor, and inexpensive in nature. Good luck, and keep us posted.

Thanks for the reply Kidrock,

Yes doing some homework indeed. The idle in the car isn't hunting but it isn't as smooth as I would like it or I think it should be so I am considering cleaning the ICV and replacing the 02 sensor as merely things to rule out. Glad to hear the rummbling with removal of the oil cap is normal.

I did see a post here on the ICV removal and cleaning so I'll attempt that with my limited skills....anything more and call Dan Jacobs typically but I am becoming brave in doing some things myself as I become more educated due to this forum and its excellent contributers such as yourself.

Best
V

I had an idle issue with my 3.2L a year ago. Replaced the ICV rather than cleaning it as it was original as far as I could tell. Took care of the problem. The elusive vacuum leak tests are probalby the worst case, so hopefully yours clears up easily.

Dwell on an 86!! He could be looking for a long time to find that adjustment.

You take off the gas cap or the oil filler cap and the idle changes?

Yes. Idle gets choppy.

Gas or oil cap?!?

If its the oil filler cap, then that is normal to have the idle go weird with it loose or off.

I don't see the gas filler cap having the same effect.

had to delete my last post regarding "dwell". I've been working midnights with no sleep, and I took a big juicy Ambien right before posting. Man, I do some crazy crap when I'm under the influence of that stuff. :(

Apologies.

Lol..no worries.

I haven't checked the gas cap. Humm

could be dwell, just call it electronic or digital dwell

The original post says gas cap, that's why I have been pestering you to clarify. OK, gas cap has nothing to do with it.

When was the last tune up?


Dood, you didn't need to delete the dwell post!! It was a cool and funny reference to years gone by. Now I look like a total Tw@t for making the dwell comment :-) Most have no idea what it is and how it's applied. Better living thru chemicals!! That is my idea of relaxing.....

LOL, sorry dude. I was checking the posts this morning around midnight and saw my post and thought, "where in the fk did THAT come from?" Totally embarassing. My wife can tell you some great "kidrock on Ambien" stories.

Oh well....I'm off to take another one. Hope I don't schitt the bed again. :eek:

Kidrock, lol! Good posts though, let's dwell on that.

Storage man, my thought is that you might be running lean already, and when you take the oil cap off, which introduces a huge vacuum leak, you might be at the outer limit of the DME to adjust fuel pulses, which might make idle choppy.

You might want to check the hose itself for the oil line "restrictor", a brass cone a few inches from the end of the vent hose that goes to the oil filler tube.

I think it's logical to check fuel pressure to make sure it's in spec. You can also have a clogged fuel line, fuel filter, old fuel pump, clogged check valve, or a dreaded vacuum leak(s) somewhere.

Check the idle switch with an ohm meter to make sure it's working, and make sure that the ICV is centered by doing the idle adjustment in another thread.