Idles fine then wants to die driving

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72dart_swinger

72dart_swinger

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I think that I am having a fuel starvation problem due to a clogged fuel filter. The motor is a 360 in a 72 dart with an electric fuel pump and a filter before and after the pump. The car will idle fine for however long you want it to, but on my way to work (4 miles) it tried to die as I pulled in the parking lot. I thought the electric choke hadn't come off and was flooding it. After work it started and idled fine, and after 2 miles was sputtering at 2000 rpm. I pulled over and let it idle and it seemed fine. I got back on the road and the last 2 miles was constant sputtering, but idled fine in the driveway. I think the tank is full of crud and stopped up the pre pump filter and is starving the motor. What do you all think?
 
Is it running points or electronic ignition?? If it's points, first thing I would do is change the condenser under the cap, if it's electronic, check the coil, heck, check that with points also!!
 
your car - bet you know what is going on better than anyone could - do as cosgig says - but follow your gut too...
 
cosgig said:
Is it running points or electronic ignition?? If it's points, first thing I would do is change the condenser under the cap, if it's electronic, check the coil, heck, check that with points also!!
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Electronic, and thanks
 
Check the fuel line coming off the fuel sending unit at the tank to make sure that the line is not bent/closed down. I've seen the hose kink and restrict flow, make sure it's straight and no kinks or sharp bends to collapse the ID of the hose...
 
Those vent lines are well known to rust up; can you actually blow through it? For that matter blow through the main line as well. Pop the fillercap first, Waaaay easier than dropping the tank for a look-see.And replace that short jumper hose at the sender, If you use gear clamps, use 4; 2 per end, with screwheads 180* apart and pointing in opposite directions,whenever possible. If that hose sucks air, the pump runs dry.

But if you have made up your mind that you have nothing better to do than drop the tank, and live in a warmer clime than Manitoba,well then,have at 'er. It may well be that the sock is varnished up.
 
72dart_swinger said:
I think that I am having a fuel starvation problem due to a clogged fuel filter. The motor is a 360 in a 72 dart with an electric fuel pump and a filter before and after the pump. I think the tank is full of crud and stopped up the pre pump filter and is starving the motor. What do you all think?
Click to expand...

I like to put my fuel filter AFTER the fuel pump.

The fuel pump is gravity fed, and the filter is a restriction to the pump "sucking" the fuel through it.

Vs after the pump where it has plenty of pressure to push through the filter with minimal restriction.

You should have the "sock" in the tank on the end of the pick-up to keep dirt from getting to the pump. You may want to make sure that your sock/filter is there and in good shape. I've seen the socks/ get old and crumble, then get sucked in and clog the fuel line.
 
sounds like my plugged filter mazda. cheap to replace. and run with cap off next time to see if its vent related.
 
krazykuda said:
Don't get rust in your mouth when you do.... LOL! :glasses7:
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Now I get your Username, heehee

I agree on the fine METAL canister filter being on the pressure side.A clean new sock and a coarse prefilter have kept my carb clean for over 15 years.The sock is huge, comparatively speaking.
And Varnish is about the only thing that clogs it. So long as you do not allow the fuel to evaporate from the tank,completely,chances are very good that it will last for decades.But if you put a strong solvent in there to expel the varnish through the system, and to be consumed by the engine;then you run the risk of the varnish collapsing into the bottom of the tank in sheets, and it's game-over.

Going back to the open vent line at the canister; atmospheric air gets pumped into that tiny line whenever there is a temperature change around the line. That means day to night and season to season.Of course as the liquid level in the tank falls, this is accelerated. Atmospheric air has moisture in it. Moisture condenses to water, which when in contact with steel and in the presence of oxygen, reacts to form rust.Rust doesn't care about up,down, or sideways,so in that confined space it quickly grows to fill the entire space; usually in the lowest point in the system.
 
Just a thought - - this could be a wiring issue too - maybe loose power or ground wire(s) - especially to the pump or the on/off switch or if it's wired directly to the steering column ignition wires.. funny thing how turns and bumps can wreak havoc on loose wires.
 
AJ/FormS said:
Now I get your Username, heehee

I agree on the fine METAL canister filter being on the pressure side.A clean new sock and a coarse prefilter have kept my carb clean for over 15 years.The sock is huge, comparatively speaking.
And Varnish is about the only thing that clogs it. So long as you do not allow the fuel to evaporate from the tank,completely,chances are very good that it will last for decades.But if you put a strong solvent in there to expel the varnish through the system, and to be consumed by the engine;then you run the risk of the varnish collapsing into the bottom of the tank in sheets, and it's game-over.

Going back to the open vent line at the canister; atmospheric air gets pumped into that tiny line whenever there is a temperature change around the line. That means day to night and season to season.Of course as the liquid level in the tank falls, this is accelerated. Atmospheric air has moisture in it. Moisture condenses to water, which when in contact with steel and in the presence of oxygen, reacts to form rust.Rust doesn't care about up,down, or sideways,so in that confined space it quickly grows to fill the entire space; usually in the lowest point in the system.
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I did put a new rubber hose on at the sender, and thanks for the idea about blowing through the vent line. So what should I do about the missing charcoal canister?
 
I don't know what the laws are where you live, but a lot of states require all emissions stuff to be working, and since that charcoal canister costs nothing in terms of engine performance;I would invite you to restore it to working condition.
 
72dart_swinger said:
I think that I am having a fuel starvation problem due to a clogged fuel filter. The motor is a 360 in a 72 dart with an electric fuel pump and a filter before and after the pump. The car will idle fine for however long you want it to, but on my way to work (4 miles) it tried to die as I pulled in the parking lot. I thought the electric choke hadn't come off and was flooding it. After work it started and idled fine, and after 2 miles was sputtering at 2000 rpm. I pulled over and let it idle and it seemed fine. I got back on the road and the last 2 miles was constant sputtering, but idled fine in the driveway. I think the tank is full of crud and stopped up the pre pump filter and is starving the motor. What do you all think?
Click to expand...

One of if not THE best tuning tools is a wide band to not only fine tune but to see what`s happening such as in your case. If you`re driving along the road and it`s acting up like you say, you can peek at the gauge and get an idea as to what`s going on such as; it shows 16.1 you are lean OR, 10.1 you`re rich for whatever reason(s). Not the end all but it tells what direction the carbs goin in then YOU get to figure out why.............
 
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