I have a 92 Ranger with the 4.0L engine. It has 110000 actual miles and was owned by a really old guy first. That being said, here's my problem: First thing in the mornings when I crank it up I have a rough idle. After about 45 seconds I can take off but it still has the rough running. Then after about half a mile it pretty much straightens out and after 3 miles it is fine. This actually occurrs anytime it sits for an extended time (like 4-5 hours). I have been told to use CataClean to fix the problem. (The check engine light does come on but goes back off after I kill the engine and restart. I have not had it tested to get the code, but several eople have suggested it to be the catalytic converter.) Has anyone used this product and what were your results? I have searched YouTube for results and they are mixed but lean more toward the product working than not. Thanks.

 

I don't see how it could possibly be the catalytic converter based on the symptoms you've described.

What codes come up? That's a good first point in the diagnosis. Something like an IAT or ECT come to mind as possibilities, but the important thing is to test and determine what's wrong rather than guesswork.

 

Never used it but like caleb said, does not sound like a cat issue anyway. Definitely sounds more like an IAC issue to me too.

 

 

IAC is the idle air controller. Also an interesting possibility, but the important thing is still to figure out what codes are actually present. If you're up for it, you can use a paperclip to read the codes.

 

Idle air control. Essentially a modern version of a "choke". Its a small selenoid valve bolted on or near the throttle body. It controls the Idle RPMS by allowing a certain amount of air past the throttle body. On a cold engine it will open more to keep a higher RPM until the engine warms up. If its stuck, or malfunctioning you will experience.... well your symptoms. But like caleb mentioned, no point guessing.... Read the codes. Even if the check engine light is off the codes will still be stored. Get those codes, write them down and post them.

 

Just to clarify, does the truck run properly on a cold start other than idle? For example, can you put it in gear and drive away with no issues?

 

 

 

Well...The air filter is brand new. Newest problem is that noone seems to have the OBD gizmo to check the codes. I haveto buy one and I am mechanically stupid. Starting to be too much headache for me. May have to sell it.

 

You do not have to buy anything. As I said previously, you can pull the codes with a paperclip.

There's information here:
Ford Ranger - Testing EEC-IV Equipped Engines


Put the clip between SIG-RTN and the Self Test jumper.

Turn the key to the start position, but do not start the truck. Run the Key On, Engine Off tests first, according to the link above. When those are complete, write down the codes. Proceed to the Continuous Memory codes and write those down as well. Let us know what those are.

 

This tool will also do the tests. No extra features, it just gives you the results as a number on the screen rather than counting as the Check Engine light flashes during the tests.

 

CalebJ you may have missed the partwhere I said I am "Mecanically stupid". lol Decided to keep the truck. Just work on it as I can until it is fixed. Thanks for all the help guys. MUCH appreciated! That is why I joined the forum.

 

And I will be ordering the tool on Amazon CalebJ!

 

Fair enough, but that doesn't mean you can't learn if you're willing. Just ask questions as you go. We all started somewhere.

 

Thanks man. I am positive that I will be asking a LOT of questions. lol