2.3L ('83-'97) Intermittent "check engine" light - diagnostic help, please.

[moretsky99]

My 96 Ranger, 4cyl, manual has a check engine light on. I had this problem a while ago. The code suggested a problem with the OBD2 sensor. I replace the sensor on my exhaust and eventually the code went away. A couple of weeks late it came back, but yesterday it went away again. What do I do?

 

[scotts90ranger]

I'm assuming you mean O2 sensor? That can mean many things...

I would start by getting a can of MAF sensor cleaner and clean the mass airflow sensor right behind the air cleaner, as easy as unclipping the air filter and spraying the sensor down to clean it up, they get gummed up over the years. Next step is to look for vacuum leaks, mainly little hoses that are somehow disconnected from stuff under the hood, most of the connections are behind the throttle body on the back side

 

[Roert42]

Can you post the exact code number?

That will be the easiest way to help you.

If there are multiple it we would need them all.

 

[Roert42]

The code does not tell you what is wrong, it just tells you the symptom.

Like when you go to the doctor and tell them your leg hurts. Now we need to figure out why the leg hurts.


Each Diagnostic trouble code is the symptom that the engines computer is noticing.

 

[RobWigglezz]

Any chance you have an exhaust leak right before sensor? One that may go away when everything heats up and expands.

 

[moretsky99]

I'll check for leaks. I'm wondering if lock-tite is required for the OB2 sensor?

 

[Roert42]

I'll check for leaks. I'm wondering if lock-tite is required for the OB2 sensor?

Absolutely not.

Most of the time they come with a small bit of never seize on the threads.

If they are backing off they are not tight enough.