My 2.8 starves out in a headwind!

[ewwebb]

I've replaced the gas tank, the fuel line, the fuel pump and the carb. I went with the stock MotorCraft two barrel. My problems began with the truck dying for lack of fuel when driven cold and dying for lack of fuel when driven over Forty MPH when warm. That was even after I'd replaced everything except the carb. Whenever it would die just waiting a few minutes would allow it to be started right up again until the next instance. I replaced everything up to the carb and finally reasoned that it had to be some crap in the float bowl. Also my A.I.R. pumb went bad so I bypassed that by removing the pulley and putting on a shorter belt. After installing the new carb the truck runs fine after warm up, but won't idle until then. Now for what I consider to be the strangest problem. When driving on the highway the truck will starve out if I'm going into a headwind! Is the mechanical fuel pump not sufficient to supply the carb. It is one of the bigger two barrels that I've seen and my milage is crap. I get maybe Ten to the gallon. The truck is an '84 with the last of the normally aspirated engines, and a Five Speed tranny. Thanks for any help.

 

[Big Jim M]

Tell us how it dies. Does it chug for a while? Does it pop and crackle for a while? I'd be looking at a coil swap was it me.
Big JIm

 

[85_Ranger4x4]

What 2bbl specifically are you running? The factory carb looks like a normal 2bbl but isn't really all that big.

The cold idle thing sounds like it might be a choke problem.

If it has ran really rich it can mess up your catalytic converter. They melt down with too much fuel and plug up which will cause many head scratching power issues.

As you are finding out, the factory feedback setup is problematic at best with age, and if you can (no inspections) it is best chucked at your worst enemy and replaced with a Duraspark dizzy and non-feedback carb.

 

[Original_Ranger84]

Honestly to me it sounds almost like carb icing... If you can start it back up within a minute or two of it dying after driving... Cause it would idle fine (or like crap if the choke wasn't working lol) and would drive a good bit even warmed up until it started sucking more cold air then it would freeze up and die, ice melts and it starts back up drive it for a bit and it dies again ice melts... ect ect. Especially if you think its acting like it is out of fuel.

With the air pump dead it isn't opening up the warm air valve that prevents carb icing...

 

[85_Ranger4x4]

Honestly to me it sounds almost like carb icing... If you can start it back up within a minute or two of it dying after driving... Cause it would idle fine (or like crap if the choke wasn't working lol) and would drive a good bit even warmed up until it started sucking more cold air then it would freeze up and die, ice melts and it starts back up drive it for a bit and it dies again ice melts... ect ect. Especially if you think its acting like it is out of fuel.

With the air pump dead it isn't opening up the warm air valve that prevents carb icing...

It could be different with every truck, but mine has never had that hooked up and while it is as cold blooded as all get out, once warm it runs pretty good.

 

[dangerranger83]

My truck never does good in a head wind. Im only getting 8-10 mpg in the winter but I think its because my truck just doesnt get to temp. In the summer it does way better. Im running the Duraspark set-up but never got to fine tuning it. I also need to find a carb that does have feed back stuff on it but it doesnt have the feedback soleniod on the back.

I would sday if it dies get out and open th hood a quickly look and see if the carb is iceing over and also take a look at the choke.

 

[ewwebb]

Hi Jim and thanks for the reply. It just flat runs out of gas. No popping or sputtering. I don't think it's an ignition problem and it does seem to be temperature sensitive. All that stopped with the new carb. I don't really know what the specs are on the carb. I know it's an exact replacement that I ordered from LMC. It runs like a striped-a---d-ape, but there's that headwind thing. I think I understand the cold-blooded thing with the idle. I know that you "waste" gas warming up an engine, but I really think it easier on the engine than working it cold anyway.

Edgar

 

[Original_Ranger84]

It could be different with every truck, but mine has never had that hooked up and while it is as cold blooded as all get out, once warm it runs pretty good.

Yeah that is very true... Mine runs great once I get it warmed up. especially since I got the heater duct replaced.

 

[Big Jim M]

First question

Hi Jim and thanks for the reply. It just flat runs out of gas. No popping or sputtering. I don't think it's an ignition problem and it does seem to be temperature sensitive. All that stopped with the new carb. I don't really know what the specs are on the carb. I know it's an exact replacement that I ordered from LMC. It runs like a striped-a---d-ape, but there's that headwind thing. I think I understand the cold-blooded thing with the idle. I know that you "waste" gas warming up an engine, but I really think it easier on the engine than working it cold anyway.

Edgar

Didja put a new filter in the fuel system? Kinda sounds like a partially stopped up filter.
Big Jim

 

[ashleyroachclip]

Fuel tank venting?
Have you had the pick up out of the tank to make sure the sock is clean...
Debris in the tank....

 

[enginepaul]

I'm not sure where you are as far as the ignition is concerned but that stock carb without all the computer stuff running it is a problem. There is a solenoid at the rear that lets in air to keep it from running too rich - and that's just one thing of many that the computer controls.
The first thing to stop doing is replacing parts unless you are sure that you need them. At this point, I'd look into the DuraSpark if it is allowed in your area.
A shop with a smog machine can tell you if it is running too rich or lean and then you can start solving the problem.

 

[kimcrwbr1]

If you using the computer you have to have all the sensors and vacuum lines working including the air pump. Did you run the codes if you dont get a 11-1-11 your mileage will suck and even then its a crap shoot if you pass on codes. Is your IAT plugged in on the air filter housing that alone will give you all the symptoms you are having. Make sure all your sensors are plugged in and vacuum lines are correct then disconnect the battery for 30 minutes. Run it for about 20 minutes to warm the engine all the way up and adjust the carb. While it is ideling and the timing is correct (check it it at 10 degrees with the spout disconnected) then disconnect the idle motor connector and adjust the idle air screws for either the highest vacuum or RPM then plug the idle motor back in. Those little motors like it rich on the idle air and because you dont have to put your foot too far down you get better mileage also. If any part of the emissions is not working or not connected the computer tells you to FO and goes into limp mode. If you dont have to pass emissions duraspark it and bring that engine to life. You will be money way ahead. Mine can sit a month start it up and go without a hickup. The only thing I can think of on the headwind is the intake air temp sensor or the choke butterfly blowing closed. Change the IAT and reset the computer and yea get the preheater duct and door working correct. Your cold starts add up to about 30 second warmup it is all any engine needs just enough for the oil to get to the upper end. Just drive it easy and let the gear oil do its job for a couple miles.

 

[Big Jim M]

In his first post

He wrote ""I went with the stock MotorCraft two barrel."
I never considered he replaced his lectric carb with one that wasn't an exact replacement.. If he did then that damn carb is the problem.
His timing is waaay too retarded from the carb being too rich..

Edgar! Ya gotta tell us what it is you did that wasn't EXACTLY stock! These lil engines don't like changes from the stock parts. Ya gotta go all the way or not at all..( I remember saying that before..)
Big JIm

 

[85_Ranger4x4]

With these little engines, they are not overly fond of stock stuff either. They rely on a Rube Goldberg combination of fuel injection and carburetion that is fond of messing up.

LMC shows rebuilt direct replacement carburetors, so I doubt it is the wrong one. It is always possible it wasn't rebuilt right though... but for $400 it should almost come not only perfect but installed.

 

[kimcrwbr1]

If that is the pic of the carb he bought it will work great for the duraspark conversion. If it dont have the feedback solenoid the computer will go into limp mode fairly quick causing all the conditions he is having. It would be like driving it around with the spout disconnected. You have to have all the components plugged in and working for the computer to work correct and you have to reset the computer if you run it with a bad or unplugged sensor. The computer will try to adjust for it but wont go backwards you have to disconnect the battery for at least 20 minutes and start again.