1985 Ford Ranger Idle Surge

[ISX_15]

quit recently my 85 ford ranger started to idle surge out of nowhere.
2.8L V6

what are the causes and solutions?
what can I check?
the fuel gauge does not work so could it be because its low on fuel?

the first time i checked it about a week ago i saw fuel leaking from the top of the fuel tank, (fuel return line?). and today i checked it again and its not leaking, but still idling like garbage.
>doesnt idle on its own
>sometimes idles at a high rpm then stalls
>doesnt start without assistance from the gas peddle

also is it possible to checks codes on this?

 

[litleblue]

Yes there are plenty of ways to do this. A cheap code reader from Auto Zone NAPA etc is about 30 bucks. If you know how to use a volt meter you can short the Self Test Input to ground and count pulses. Kind of a pain in the ass but it worked for me fine in the early 80’s.

 

[RonD]

1985 2.8l Ranger has a carburetor, so no "Return line"
It has a mechanical fuel pump on the engine

If there is gasoline leaking from the top of the tank then there is a broken fuel line and you should pull off the bed of the truck and have a look, you can also fix fuel gauge at that time

But first check the filler tube, that runs from the side of the bed to the tank, where you put the gasoline in
These can crack and leak, so it could look like fuel is coming from the top of the tank

With a carburetor, the up and down idle can be several things, a vacuum leak is most common

 

[ISX_15]

1985 2.8l Ranger has a carburetor, so no "Return line"
It has a mechanical fuel pump on the engine

If there is gasoline leaking from the top of the tank then there is a broken fuel line and you should pull off the bed of the truck and have a look, you can also fix fuel gauge at that time

But first check the filler tube, that runs from the side of the bed to the tank, where you put the gasoline in
These can crack and leak, so it could look like fuel is coming from the top of the tank

With a carburetor, the up and down idle can be several things, a vacuum leak is most common

almost a year later, i have money, and time. having my old man look at it he noticed there was a vaccum leak on my PCV valve, which happened to be a 2 way instead of 1. plugged it up and now it idles and its own. However, it doesnt really hold its idle if that makes sense, it will idle, then i can feel the RPMs drop and come back up. this is a issue because it sometimes stalls out when im coming to a stop whilst downshifting.

would it be "okay" if i just adjusted the idle to compensate for it?

 

[franklin2]

Turn it up a little. Whatever it takes. Just make a note of the direction and how many turns you make so you can put it back if you have to.

 

[ISX_15]

Turn it up a little. Whatever it takes. Just make a note of the direction and how many turns you make so you can put it back if you have to.

and where on the carb would i find the idle screw?

 

[franklin2]

On the driver's side. There is more than one. The one I would adjust moves the whole idle motor assembly back and forth. Just turn the engine off, take the aircleaner off, and then move the throttle while looking at the lever arm. You can see what it stops against, and you will also see how the motor on the throttle moves in and out as the computer adjusts the idle speed.

 

[ISX_15]

On the driver's side. There is more than one. The one I would adjust moves the whole idle motor assembly back and forth. Just turn the engine off, take the aircleaner off, and then move the throttle while looking at the lever arm. You can see what it stops against, and you will also see how the motor on the throttle moves in and out as the computer adjusts the idle speed.

life saver, i will do that, also ill clean out my jets and clean out my carb.