02 Sensor

I bought a universal 02 sensor from my parts store and it only has one wire coming out of it. The one on my truck has three wires coming out of it. Do i just need to take it back and get the 50 dollar one or is there a way to make this work. I really hope this makes my truck run right. It wouldnt idle or run or hardly anything. I got it to start really fast now and idle most of the time. But it kinda spudders all the way up to 3 grand. I dont know whats wrong with it. I have replaced the fuel filter, checked spark. checked fuel pressure, cleaned throttly body and iac. I dont know much else to do. Any help is appreciated.

You've got one without the heater. Given how critical the O2 sensor is to the engine running right, I'd drop the $50 and get the right part, especially if you have problems with the engine anyway.

What are the specs on your vehicle??

Your symptoms for a Chrysler PCM does NOT sound like a bad O2 sensor. As well, if its a chrysler PCM, you can get the fault codes which will tell you if the O2 sensor is bad (although thats not full proof).

If your vehicle needs an O2 sensor with a Heater, then get the right O2 sensor. The Chrysler System will give you a constant Check Engine Light if your missing the heater for the O2 sensor.

I know nothing about the RENIX system, if thats what you have, then this might not apply at all, but your symptoms sound more like a bad MAP sensor or TPS. I'd find a trouble shooting guide and try to narrow it down, you'll go mad and broke just replacing one part after another in hopes it will finally fix it.

OK - "Year/engine?" I've had to ask this so many times that I should probably just bind it as a shortcut...

If you have the ChryCo HO (OBD-I from 1991-1995, OBD-II from 1996-2001,) the sensor might work, but you'll get a "HEGO Sensor Heater Failure" code that won't go away. If you have the RENIX (1987-1990, pre-OBD,) the sensor will not work - the sensor you've got is likely a voltage generator, and the RENIX system uses a variable resistance with a reference voltage pushed through it. It really does help to tell us what year/engine you've got...

However, I also concur that this doesn't sound like a HEGO sensor failure - I'd start by check anything to do with vacuum (manifold bolts, vacuum lines, MAP sensor, and gaskets, for starters.) Does it level out some once you go above idle?

Loose manifold bolts are fairly common on inline sixes (not just Jeep - all sixes) because the sealing surface is so long. I've found it helpful to returque the bolts about once a year as a preventive measure - I'll usually find one or two loose, and the idle will settle down.

If you want a quick way to check for vacuum leaks, get a can of carburettor cleaner, let the engine idle (but do NOT let it warm up - a lot of gasket-related leaks will go away if you let the engine warm up!) and spray a fog around any vacuum seal and all vacuum lines. If you see the fog get drawn in anywhere, and the engine RPM goes up, you've lessened the search for your leak considerably.

I'd also check the connections for the MAP sensor, the Throttle Position Sensor, and the seal around the Idle Air Control motor - those can also cause the symptoms you describe.

And, when having us help you troubleshoot, it's really helpful to give us all the information you can - starting with vehicle specifics. Putting a line like:

88XJ/4.0/BA-10/D30/D35 (3.07)

Is a huge help - read it as "88 Cherokee w/4.0, Peugeot BA-10/5 transmission, Dana 30 front, Dana 35 rear, 3.07 gears" and you're on the right track. If any of us here are psychic, they're hiding it well (me, I'm psychotic, not psychic...) Also detail any engine mods - if you've done a stroker, how long ago and what you've done (you can list that as "4.0 + 258 + .030" - 4.0 block, 258 crank, bored +.030" - or similar.) There is no such thing as "useless information" - we either haven't figured out what to do with it yet, or it comes in handy later. Making everyone go to your profile is time-consuming - and for people like me with several vehicles, no help anyhow. Help us help you.

5-90

Sorry about that. i have been posting so many different post on here trying to get all the responses i could i must of forgot. Its an 89 Jeep comanche with the 4.0. with about 165 K on it. I just replaced the fuel injectors, along with plugs wires fuel filter, and i also cleaned the throttle body and the iac. I also had my MAP sensor tested at Auto Zone. Thats all i can think of right now. It will just start idle up and die if i dont help it. It doesnt rev up very well at all until past 3 grand. After that it seems to run pretty well. Also if i put it in gear i cant go anywhere. It will just sputter and backfire through the intake and not go anywhere.
Thanks
Brandon

OK, that does help...

First of all, return that sensor - it will not work. It's the wrong action - you'll be better off going with something specific to RENIX, and get it from AC Delco or Bosch (you should have no trouble finding those locally, and I usually go with Delco.)

Start your search for vacuum leaks at the line going to the MAP sensor, you'd be amazed how often that damn thing cracks. When I get a chance, I'll be eliminating that Nylon line entirely - but you can "patch" it with a short section of rubber vacuum hose in a pinch.

Also, I'd check TPS adjustment/action - I just had something like that on my 88XJ. Started out as a wicked flat spot from 2400-3000RPM, and then grew into an idle issue as well.

Start there, and maybe check the rest of the things I mentioned earlier - and post back with your results.

5-90

I have been getting told alot to check the TPS. I dont know really how to do that. When i look at it i see like 8 wires coming from it. four go to a plug and the other four are hard wired into matching wires with heat shrink on it. I dont think i have a volt meter or anything. Is there any other way to check it? does anyone else have any suggestions? I think tommora im going to double check my fuel pressure. But it seems to run fine above 3 thousand RPMS so im not thinking its that but it cant hurt to be sure.

Brandon

Ok today i took wd 40 and sprayed it in all the connections. Still didnt help anything. I also unplugged my 02 sensor and it ran the same so i dont think thats it. But i did make one mistake. i loosend the top bolt on my tps. Cuase i read that u can loosen it and turn it to adjust it. Well i loosend it and moved it up and went to tighten it back and broke the bolt. So i think im royaly screwed. I just closed the hood and went to school. Tonight after work i might take the tps off and see if i can get the bolt out. I looked again at my tps and it has 6 wires coming out of it. 3 go to a plug in that is supposed to have four but one is just gone. and the other three are hard wired into other wires that run off somewhere. Can you adjust your tps or was i reading something wrong. And does my not running problem sound like a bad tps? It will take forever to start then it will idle up then just die. If i give it gas it just runs like crap. Almost exaclty like a cold carburated car. And if i get a new tps do you have to adjust it or is just a take the old out and plug new one in?

Brandon
89 Jeep Comanche 4.0 4x4

Ouch.

Do NOT spray WD-40 in electrical connections - it's a "water displacer," and will coat the terminals and make the problem worse. Either Electrical Contact Cleaner (better auto parts houses or hardware stores) or the NOT "non-chlorinated" brake cleaner will work well (don't use the "non-chlorinated brake cleaner - that suck bad enough on brakes.)

Since you have the RENIX system (1987-1990) and the AW4, you have the "two-part" TPS. The 3-cavity plug goes to the ECU, the 4-cavity (with only three wires in it - it's supposed to be that way) goes to the TCU.

We suggested adjusting your TPS because it can cause symptoms like you are describing - and there are quite a few writeups here on how to do just that. You will need an accurate digital voltmeter, and either "backprobe pins" or a couple small paper clips to straighten out, and crocodile clips to attach. If you can't find the writeup on adjusting the thing, let me know - I can copy it out of the FSM for you, but it takes longer to tell than it does to do, and I'm just not up to that much typing if it can be avoided...

Oh - and anytime someone tells you to check/adjust something, and you're not sure what to do, DON'T. Ask first - it's how you learn...

And, did the bolt just break in two, or did it strip? If it stripped, you'll probably have to Heli-Coil the hole, or tap it oversize - if the bolt snapped, you're in for drilling it out and getting screw extractor in there - and they may not make one that small that is easy to handle (it's either #10-24 or M5-.8, as I recall...)

5-90

We were all young or inexperienced or both once upon a time. In my case it was long before web fora existed. I longingly recall how many sockets I broke trying to get the last two head bolts undone on a Corvette 283 V8 because my best friend and I didn't know anything about torque patterns. Not long after high school, but a good 30+ years ago, I learned something about buying auto parts termed "universal" and/or "universal fit."

Don't.

I dont know if unplugging the O2 sensor is going to give a change in the way it idles. If its already running like crap, and the O2 sensor is bad its not going to change. I had the same symptoms you described in you earlier post. Changing out the O2 Sensor fixed my no idle, having the feather the gas pedal to keep it running problem. And like said before. get the OEM one not the universal.

Ok im confused now. I have been looking at other post.. alot of other post. And what im getting from some of them is that the 02 Sensor doesnt do anything until the engine is warm. So having a bad one would only produce problems when the engine is hot. But some other post say that a bad one will make the truck run bad all the time. Im at a loss here and i dont really know what to do. Today at work i looked at a bolt extractor and i think we sell one small enough so im not worried about that. I i guess im going to look around the garage to see if i can find a voltmeter or somthing. If replacing my o2 sensor and checking my tps doesnt work i guess im gonna have to take it to the dealership becuase this is my DD and getting rides and driving my dads Geo kinda sucks
thanks
BRandon

The oxygen sensor has to reach operating temperature (I don't recall exactly - but I'm inclined to think it's about 1000*F) before it generates a reliable signal. This has nothing at all to do with engine temperature - that's why the sensor usually has a heater in it. Your engine doesn't hit operating temperature for several minutes - a HEGO sensor is usually ready in 30 seconds or so.

However, the HEGO should not cause any serious idle/running problems - you'll notice it going out when your fuel mileage starts to get crappy. It provides the electronic controller with post-combustion feedback, so it knows whether to adjust the AFR and which way. Your engine will run without a HEGO sensor - which is why I directed you toward something else. I know that the MAP will cause symptoms like you describe, the TPS can, and vacuum leaks damn sure will! And, it's funny just how often something so frustrating can be caused by something simple...

5-90

Well i took of the MAP sensor and had it tested at autozone and they said it was good. I dont think i have any vacumm leaks beacuase it has been gradual. At first (about three weeks ago) it ran fine but when it hit second gear it would bog down. And then it just went downhill from there. For awhile it wouldnt even run. Now i got it to idle with some help. My dad said he thinks its running rich becuase when we cleaned the throttle body everything was really black. So that leaves the TPS. But from what ive been reading the TPS cuases bad high RPMs and high rpms is the only time my truck runs good. Tommora im gonna replace the hard line goin from my MAp sensor with a soft vacuum line and see if that helps. Ive looked at it but i dont see a whole.
Thanks
Brandon