joeveto

Hey all, I took the car out today and washed and waxed it. I put my foot into it a few times, and I noticed a really bad bog. It's the same bog that presented itself during my first few drag runs, last year. When I filled the tank, the dogginess went away.

At the dragstrip, I was pretty sure it was fuel starvation caused by the fuel being thrown to the rear of the tank. But today, even without hard launches, the car was just bogging.

Do any of you experience this same thing?

Captain Morgan

I've experienced it when the tank is low also, but usually only if I'm getting into it hard. It could also be a problem with the carb and it's possible the cat is clogged. Does it only bog at certain RPM's? Mine usually wouldn't do it until near top of third gear, unless the tank was REALLY low, which I usually try to avoid.

SpyderD

I never experienced it but I read somewhere that water from years of condensation is at the top so that when you start running low on gas you start syphoning off the cruddy dilluted gas. Some sources say to never let your gas run near dry.

mrvette

SpyderD is about 110% correct there, and damn if I can figger out just exactly how the water get into the tank, I have a large problem with it here in Florida, and suspect strongly it's a problem with the underground tanks at the stations in general, I know for sure one station, a BP, which had it's tanks changed some years ago was pumping about 1/2 water....doesn't upset the carb'd van or any other car I heard of....but when I stopped using their gas the problem was greatly diminished....but not entirely eliminated....

since the large episode with them, over 5 years ago, the tank has been purged about 3X......

now I have DPFI on the car, so those problems are worse in my install than a stock car, I"m sure....but I still have a hell of a problem figgering out just HOW the water gets in the tank...and why this car is so sensitive to the problems, when other car are not, my van being one of them....

GENE

lostpatrolman

Water sits on the bottom of the tank. If you take the gas cap off, you can usually see the water if there is any. It will ball up at the low spot in the tank, somewhere in the back.

mrvette

Yes, Lost, you are correct, I remember spotting it once, sort of funky looking, and sure enough after draining the tank and drying it out....the problems disappeared again, for a time....

still the question of just HOW that crap get IN the tank in the first place, and why THIS car is so sensitive and others are not....bugs hell out of me....
no good technical reason I can find.....

GENE

Tominator

SOAB, could this be my problem :confused:, last weekend my car was running great then started booging some. When started running bad I had a 1/8 of a tank in it.

Will check this out.

mrvette

Well you know, all attempts to 'calibrate' my fuel gauge have been less than sucessful....dismal is more like it....I have taken to putting a clean stick into the tank and just getting a measure of it....I notice the bog problem happens just about when the top of the fuel sock is exposed....I use a mini mag lite to see it, and look for water....it's one remaing bug in the car I can't seem to get a handle on...along with the silly recirculating fuel and consequent vapor/float/ smell, stuck closed evap emissions ball, and the like....
essentially, I'd love to get an '82 tank for my car...pick up some 8 gallons and have done with all this BS....I"m told it won't fit though....well anyting can fit with some fab work....anything....

GENE

Captain Morgan

Never considered water in the tank. Aren't there some products on the market to remove water from fuel? Do they work?

isosceles

mrvette,I'm in FL too. From what I understand, water accumulates in the tanks down here because of condensation from the heating and cooling of our humid air.
I've owned several boats and the rule of thumb among boaters is to fill the tanks when you come back. This reduces the amount of space to hold air. The less air, the less condesation.
I know C3sharktank has a water separator under his tank, much like I've had in some of my boats. You might send him message to see where he got the plumbing for it.

mrvette

Triangle, I find it kinda hard to see just how an gas/water separator/filter can help me....as if the water is being sucked up, there is no gas for the engine...and given the constant recirculation required of a DPFI system, I think its' a problem.....

I need solve just exactly where the water in the tank on a recurring basis is coming from....that's something Im sure is not coming from the car itself....if it was so it seems the other cars would suffer the same fate...even my old crabd' Dodge work truck....

still think it's a gas station problem...

I been all OVER that tank many times, and it's NOT there.....

GENE

hudman

Sounds like water to me. I spent a fortune with a mechanic trying to find that one. The mechanic finally found the water, but it came back. Some local guys here helped me find the cause.

I have run the water in the tank rabbit several times. Mine was getting in because someone had installed the rubber sleave around the filler backwards and the nipple was facing forward and not backwards. Thus, the water would not run out. It would just puddle up in the rubber bowl. Also, the sleave was dryrotted, so water would leak through to the base of the filler neck. The neck had been overtightened at some point (probably by the previous owner tightening it down to try and keep the water out!) and the base of the filler neck was warped and did not sit flush with the top of the thank. All of that combined with a old cork gasket meant water was leaking through the sleave/bowl and into the top of the tank. I replaced the filler neck, cork gasket, gas cap, rubber sleave and drain hose/nipple. No more water in the tank.

AndreG

I had a really tough time with this and an embarrasing 8 month tale to share with it. Fuel level would get to about 1/3 of a tank, engine would start to knock, ping and just generally suck. Spent countless hours trying to figure out the problem looking in the tank and siphoning gas. Replaced all filters, worked on my carbs repeatedly, installed a high pressure pump, regulator, pressure gauge and replumbed the entire fuel system. Put in an MSD ignition with adjustable timing control. Still no better regardless of fuel pressure settings or timing!!!!! Finally found a two foot long soccer sock floating over the fuel pickup. Probably had been there for 3 decades given the attractive "harvest gold" striping on it. I can't tell you how many times I looked in the tank with a flashlight and it was NEVER visible until it finally hung up on the pickup and remained where I could see it! Quick fishing expedition with the BBQ tongs (much to the dismay of the wife) resolved the dilemma. I can't tell you how many hours and countless $ I spent diagnosing this problem. I felt like such such a twit when I eventually found the cause. Took the entire satisfaction out of resolving the issue! Being the ever present optimist I guess that on the plus side they were all things I wanted to do anyway and this provided me the justification;-)

Just gotta love the experiences working on old cars where you are probably owner number 92;-)

I hope this open revealing and sharing of my total humiliation serves of use to someone even if purely for entertainment purposes or simply a shining example for other to not follow!

Look for socks;-)
-Andre

verskel

Car gets doggy when fuel tank is low

Thought it was a 'headline' to a great story ! :jester

"Today witnesses spotted a car, low on fuel, darting at neighborhood dog. The driver of the car is currently being detained for questioning with this being his 3rd victim this week. The owners of the dog are suing for animal cruelty." :lolg:

Sorry, it just sounded like a Jay Leno take-off.....
** No offense to dog lovers out there either......

MotorHead

Many years ago a friend of mine thought his car went faster with a full tank of gas, his theory I guess was more gas more speed hmmmmm maybe I shouldn't have laughed at him :lol:

ejr76

I had a similar problem with my car. I had the gas tank removed and that "sock" filter replaced. Thought the problem was over, at least until yesterday. The car was running great until the way home when once again it started missfiring at around 3,500 RPMs. The tank only took 11 gallons when I filled it up, so it started misbehaving with about 8 gallons still in the tank. Once it was filled to the top it ran great again. The one thing is: I had a "bladder" 18 gallon tank installed when they redid my body. They said the original 21 gallon didn't fit with the retro back end. The car never had this problem prior to the retro work. Could there be something from the old setup that isn't compatable with the new tank?