Fuel?

[patrick66]

Took the '66 Coronet out for a spin a few days ago. The weather was far too nice not to take it out. Started right up, drove for about three miles at 45mph, then entered the freeway. At about 2,800 RPM, the car was cutting out, like it was running low on gas. Since I was five miles from an exit with fuel, I babied the car until I exited. It did stutter a few more times until I got to the pump. Filled it up with mid-grade (89 here) 100% gas. Checked the plug wires, fluids, fuel line and normal checks. Only took eight gallons to fill up, so it had fuel to begin with. Once I added gas, it seemed to do OK, stuttering only once at about three grand (80 mph). Drove it again yesterday for another 25 mile drive, and it did fine. This time, I checked the cap, rotor, and wires again; plus looked for leaks and loose wires. Fuel filter is new. All good.

Oil pressure is normal. Water temp is in the center of the gauge. No leaks or loose wires/errant sparks. Vacuum is steady with no wobbling needle. In Park, I can bring the engine up to around 4,500 RPM without stutter or backfire.

All I can figure is that I had poor-quality fuel, and the added fresh fuel diluted that enough to make what was in the tank useable. Thoughts?

 

[WileE]

Depending on conditions, you may have water from condensation in your fuel. Put some dry gas in.

 

[patrick66]

I was figuring condensation later, too. I think the added fuel took care of that problem. Dry-gas is a good idea, in any case.

 

[PurpleBeeper]

Old gas (older than 1-2 months) can do that too. The more volatile part of the gas evaporates first leaving you with the harder to burn stuff. For water, use Heet.... the red stuff works better. It is designed to absorb water (that's how it melts frozen gas lines really)

 

[Ranger16]

For what it's worth, when I start my car every spring it has gas in the tank that is at least 6 months old and I have never experienced any such problem. All gas here is 10% ethanol (which absorbs water, precluding the need for Heet) so that may account for the lack of water.

 

[vintage chromoly]

Ethanol creates the problem, it doesn't mitigate the problem.

 

[patrick66]

I won't let any of my vehicles anywhere near a pump with corn-squeezin's in it. It is the worst thing you can put in a gas tank. Made that mistake once in my wife's Dakota, and it truly ran like **** until I put real gasoline in it. Fortunately, it was only four gallons in a nearly empty tank, so that was rectified the next day with 24 gallons of real gas!

 

[Ranger16]

We don't have much choice around here, but honestly I have not seen or had any problems with the 10% ethanol (other then the obvious lower BTU's and slight reduction in mileage). Other than that, I'm not sure what the big downside it. Don't get me wrong, I wouldn't use it................... if I had a choice.

 

[WileE]

Air has moisture in it. With a vented system, condensation will occur. That's why it's prudent to completely fill the tank (no air inside) when leaving it sit, add stabil for an extended period of time.