Car almost dies like it's running out of gas?

[Cobrastrike]

This happens every time I drive my car! Fuel tank of gas or half of a tank full. Can't seem to find the problem.
Has good pressure, 40 on my gauge. Seems to happen more often when it's warm out. The fuel pump is not in the tank. Could this be my problem? My car has a 5.0 95 model supercharged. Any ideas at this point would be appreciated.

[Art Caley]

Hard to tell from your description. You still running EFI? Could be the pick up of the fuel at the tank. Also symptoms of stalling could be many other things too, such as MAF sensor, etc.:confused:

[Cobrastrike]

:confused:
Hard to tell from your description. You still running EFI? Could be the pick up of the fuel at the tank. Also symptoms of stalling could be many other things too, such as MAF sensor, etc.:confused:

Yes on the EFI. MAF sensor changed no effect on problem. Its really strange youll be driving along and all at once it will sound and act just like it was running out of gas. sputter and spit and almost die then it will gradually get better in about a half mile and it my not do it again until the next time i drive it.

[Hankl]

Have you checked any of the filters in the system lately? Blockage can be in the tank also as suggested.

Hank :cool:

[Cobrastrike]

Have you checked any of the filters in the system lately? Blockage can be in the tank also as suggested.

Hank :cool:

Yes the filters good. I will pull the tank this weekend and see what i can find. :cool:

[David Hodgkins]

Here's a stab in the dark...

How about vaper lock? Is your gas line insulated, or very close to your headers?

:)

[Cobrastrike]

Here's a stab in the dark...

How about vaper lock? Is your gas line insulated, or very close to your headers?

:)

Gas lines not insulated, in the engine compartment the closest they get to the exhaust is about 5" away. Do you think it could be vapor lock due to
engine compartment heat? If so do i need to put a wrap around the lines or reroute them?:)

[David Hodgkins]

I will admit I'm not an expert at this condition. Here is some intro material for you to read and to help you ascertain if your situation fits into some of the criteria related to vaper lock:

http://en.wikipedia.org/wiki/Vapor_lock

Here are a few highlights:

"Vapor lock is a problem that mostly affects gasoline-fueled internal combustion engines.

It occurs when the liquid fuel changes state from liquid to gas while still in the fuel delivery system. This disrupts the operation of the fuel pump, causing loss of feed pressure to the carburetor or fuel injection system, resulting in transient loss of power or complete stalling. Restarting the engine from this state may be difficult. The fuel can vaporise due to being heated by the engine, by the local climate or due to a lower boiling point at high altitude. In regions where higher volatility fuels are used during the winter to improve the starting of the engine, the use of "winter" fuels during the summer can cause vapor lock to occur more readily."

and...

"Most modern engines are equipped with fuel injection, and have an electric submersible fuel pump in the fuel tank. Moving the fuel pump to the interior of the tank helps prevent vapor lock, since the entire fuel delivery system is under positive pressure and the fuel pump runs cooler than if it is located in the engine compartment. This is the primary reason that vapor lock is rare in modern fuel systems. For the same reason, some carbureted engines are retrofitted with an electric fuel pump near the fuel tank.

A vapor lock is more likely to develop when the vehicle is in traffic because the under-hood temperature tends to rise. A vapor lock can also develop when the engine is stopped while hot and the vehicle is parked for a short period. The fuel in the line near the engine does not move and can thus heat up sufficiently to form a vapor lock. The problem is more likely in hot weather or high altitude in either case."

HTH,

:)

[rschoeni]

Fuel cell or tank? If you have a cell the foam may deteriorating.


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/bs

[Cobrastrike]

Great info, thanks. It does sound like that is the problem. I dont have my pump in the tank, but after reading you info sounds like a good place to start. ill get one on order and change it out when it gets hear. Do you think i still will need to wrap the fuel lines in the engine bay...????

[Cobrastrike]

Fuel cell or tank? If you have a cell the foam may deteriorating.


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/bs
Gas tank, not fuel cell....

[rschoeni]

Are all the injectors ticking when it runs rough? Screwdriver=poor man's stethescope.
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/bs

[Cobrastrike]

Are all the injectors ticking when it runs rough? Screwdriver=poor man's stethescope.
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/bs
Hmm, not that i know. It happens only when im driving the car. It will stall and i will pump the gas or floor it and it will jerk and spit and in a few seconds it will be ok.

[Joe]

Well I'm never a fan of just replacing parts, but heat related problems can be a pain to diagnose. My uninsulated steel fuel line is 3.5 inches from the closest header tube and I've never had a vapor lock problem. Note, I live in N. Texas and things get pretty hot around here, like they do in Oklahoma.

If you can confirm that fuel is being properly delivered to the engine, then you might want to look at ignition. A bad Ford EFI TFI module is a known component that often will start to fail when things start to heat up. You could rule that out for about $44.00. You could play around with it and try to insulate the module from engine heat to see if the problem goes away, before buying. It was a bad enough problem that Ford eventually moved the TFI off of the distributor and mounted it on a heat sink in some vehicles. If you remove the TFI module, make sure there is sufficient heat sink grease between the module and the mounting plate. The grease helps to transfer the heat from the TFI module to the mounting plate which acts as a heat sink.

http://www.therangerstation.com/tech_library/remote_tfi.htm

http://t3.gstatic.com/images?q=tbn:ANd9GcQNd14APol3R8XR5TUg_3prjWlFoYsWY T53aZbPZjYNxrkmNpWG

http://www.autozone.com/autozone/parts/Duralast-Ignition-Control-Module/_/N-9ci7x?itemIdentifier=118646&_requestid=1071858

[Cobrastrike]

Yes, I have replaced tfi control module and the distributor. Also replace the Msd control box, changed out the coil.
It's driving me crazy trying to find it....arhhhhgh!

[Brian Z]

I just had a similar problem in my 88 mustang. It was cutting out when I was cruising along at random. It was my TPS sensor. You can take it off and see if the plastic is worn out inside of it. Also, does you gas tank have a vent tube on top?

[Cobrastrike]

I just had a similar problem in my 88 mustang. It was cutting out when I was cruising along at random. It was my TPS sensor. You can take it off and see if the plastic is worn out inside of it. Also, does you gas tank have a vent tube on top?

Thats what i thought as well, i have changed it. did not help. Tank does have vent on top. I hate problems like this.....:(

[David Hodgkins]

A couple more ideas, based on a similar experience I had shortly after finishing my build...

I don't know the name of the inline fuse I have near my starter, but it is about 1"x2" and mine has a red rubber cover. I had a situation where my car was cutting out as well. I replaced my TFS to no effect. It turned out that after I replaced that fuse, my problem was solved. It turned out to be that fuse, but I'll also mention that checking the wiring connections is good to do because it never hurts to check.

Look at replacing that inline fuse. That fixed my issue.

:)

[Joe]

PM sent Cobrastrike.

[efnfast]

Is your return line atleast the same size as your feed line?

Have you got it on a dyno to make certain your a/f is okay and not leaning out because of a bad tune?

[Cobrastrike]

Is your return line atleast the same size as your feed line?

Have you got it on a dyno to make certain your a/f is okay and not leaning out because of a bad tune?
Return line is a bit smaller! Would this cause a problem....?
Never been to a dyno yet, seems to be running rich most of the time..

[efnfast]

return line should always be at least the same size as the feed otherwise you might have problems.

I say might because in my research I'd say 3/4 of the people who undersize the return line have problems that are solved by matching them, 1/4 get away with it with no problems. I can't explain why some have problems and some don't when it's smaller than the feed (i.e., it doesn't have to do with f/i vs n/a, nitrous vs no nitrous, etc.. etc...)

If you're running a s/c that gives you less margin of error until your engine goes b00m, so you really should have it on the dyno to watch the a/f to make certain it's a solid 11.8 at WOT and it isn't leaning out anywhere.