What are your thoughts?

Greetings all! It's been a while but I want to start driving the car again... For the unusual reason of saving gas... LOL!

My car has, for a long time, had issues with driving. It fires up excellent cold. Typically runs great. And then I turn it off, after turning it off and staring it back up within short period of time (most common filling with gas or running into a store to grab a drink) it runs extremely rough and will even stall out if it's not moving. IF I park it and go in a store or something. Give it 20 mins to cool off and then start it back up it runs like a champ. Any ideas what could cause this?

Thanks in advance to the community I have missed very much!

 

Little more info, it's a 200 I6 automatic.

 

What is the state of tune on your six cylinder? In other words, how long has it been since the engine had a good tune-up? Still running a points and condenser system?

 

Does it run rich when it's stumbling? I'd have a look at your choke to make sure it is completely open, and that the clockspring is adjusted correctly. I believe mine is set at two notches to the rich side. I can check tonight when I get home.

BTW, I have seen pictures of this car on FB and it is a SHARP looking car!!

 

If you were describing a marine engine, the symptoms would indicate classic vapor lock. If the fuel is getting too hot for any reason or if the fuel pump is pulling against a restriction between the tank and the pump (clog, kink etc), it could be vapor locking.

Definitely check the state of your ignition components first, as was mentioned earlier. Vapor lock is not very common in automotive applications, but it can happen.

 

Choke is something I have adjusted and got it to where it runs/opens the best. (to my knowledge) if you could check what yours is adjusted at though that would be a good reference point!
And it has been tuned up all around, new plugs wires dist points...even the carb is new on the thing as my old one had a stripped screw that was causing issues. I am thinking on purchasing electronic ignition and dist. set up for it, but not sure if that could increase the running of the vehicle?

 

I agree with rotorr22 it sounds like a heat soak vapor lock problem, how old is the fuel pump?

 

If you are confident that your tune is good, I would doubt that going electronic will cure your Maverick's ills. I believe as rotorr22 the fuel system could be the next area to check. Is your fuel system completely stock? That includes lines and filters etc. Are the rubber fuel lines under the car in good order? There should be rubber lines under the car at the driver's door and at the tank. Deteriorated rubber lines may cause a weak fuel pump to operate poorly. Old fuel lines that look fine on the outside will decompose internally causing a partial blockage especially with todays fuels. This also applies to rubber lines under the hood. If you are not sure about any of these lines replace them with good quality fuel line. Are there any non-stock filters or pumps under the car that have been added?

Some good close-up pictures of your under hood fuel and ignition system might be helpful. Give us pictures from the time the fuel line enters the engine compartment until it reaches the carburetor. No air cleaner please. Does outside temperature have any impact; cold, hot, real hot? Do you have a temperature gauge on your Maverick or just the light? If you do have a gauge, what does it read at normal operating temperature? Answers to all these items might be helpful in the diagnosis.

 

You mention that the carb is new. You might have to take it apart and see if the float is adjusted properly. You may have very little fuel in the bowl after shutdown and if so, the heat soak will make it worse. An electronic ignition will not correct the symptoms you are describing.

 

As JL Mav points out, it may be a weak fuel pump. The items I have listed above exasperate the problem.

 

I do believe the fuel lines are all stock. I have not changed them in my 5 years with the car (can't believe its been that long already!!) the pump was replaced, but I have not driven the car a ton since I got the my truck. When I get home from this amazing coast trip I'll pull her back into the garage and take a look at the lines. Float may be something to look at also as I don't recall adjusting that at all either (though it has sat for a majority of the last 2 years. Look forward to looking into the issues and getting some pictures if I can when I get home!

 

If it smells like gas after you let it set for awhile the float may be set too high so that when the fuel heats up it will flow out of the bowl into intake and then the car will run too rich until it all evaporates. This can be a bad thing especially if you have a backfire while starting up the car.

 

I do believe it smells of gas... But I can't remember. I will definitely check!

 

hold the pedal to the floor (don't pump it) and try cranking it like it's flooded.

 

One notch in the "rich" direction.