Car occasionally will not start

A few weeks ago our car began not starting. 2004 Ford Taurus. We live in Nashville TN and the first day it didn’t start was a bit cold. We decided to take it to the garage the next day. next day it was rough at first but started. The mechanic could not find anything wrong with the car, but suggested it may be the fuel pump, malfunctioning intermittently. It ran fine for about a week and one cold morning would not start again. We towed it to the garage where, after they moved it indoors into a warmer environment, got it started and could not find anything wrong again. They checked the fuel lines and they were working fine. The mechanic suggested that it could be high ethanol gas. We started using better gas. It ran fine for a couple weeks and again would not start (in the morning) while on a trip to Atlanta. Had it towed to a shop owned where they got it started (Indoors again), did a precision tune up, new battery, s belt, air filter etc. The one thing they found was some debris in the air filter housing which they cleaned out. It ran fine for about 2 weeks and again this morning would not start. It actually started rather rough but the idle quickly slowed and it stopped. It would not start again. It cranks but will not start. Any thoughts?

Take a rubber mallet, slide under the car and give the bottom of the gas tank a couple whacks. If the engine starts after doing this, the fuel pump is going out.

Tester

Everyone should have these 2 things to narrow down a non running car.
A can of name brand starting fluid with straw. Follow black round tube from air cleaner to the motor and loosen at motor and spray, then try to start. If it starts trouble is fuel related.

To check spark use this between plug wire and plug.

http://search.harborfreight.com/cpisearch/web/search.do?keyword=spark+checker&Submit=Go

Tried whacking the tank on multiple occasions (garage suggested this too)… But it has never helped. Thank you though.

We will try the starting fluid idea soon… Thanks.

It has consistently had spark when checked, so that has never been the issue.

Try this.

Turn the ignition switch on so the dash lights come on for two seconds, and turn the ignition switch off. Repeat this a dozen times. Now try starting the engine. If the engine starts, the problem is probably with the check valve in the fuel pump assembly.

Tester

Got the starting fluid, removed the air intake hose, opened throttle, sprayed fluid… car started right up! It ran rough for a few seconds, replaced the air hose, then it smoothed right out. So now what do you think the ultimate solution is? And thank you so much for your post.

Tried this as well. It did not start after this process either, although you could hear the fuel pump working when you turned the key. Also you could smell the fuel.

You shouldn’t be smelling fuel. Check to see if the fuel pressure regulator has developed a leak.

The regulator is located on one of the fuel rails. It’s a small metal canister with a single vacuum hose attached. Remove the vacuum hose from the regulator, and if fuel leaks out of this connection the regulator is leaking and needs to be replaced.

Tester

We will try to find this and do as you describe. Will let you know what happens. Probably do that tomorrow as it’s getting dark now. Thanks for your help!

Have you tried starting it with the gas pedal pushed about 1/2 way down and no starting fluid? If you haven’t, and it will start that way, then it is probably the idle air bypass valve starting to get stuck. Otherwise, it would be a fuel problem of some kind.

Keep it running for a bit with fluid but do not over do it. It may stay running after that.
What about fuel filter?

When you say “fuel problem of some kind” do you mean what is actually in the fuel or fuel delivery?

Yea, after we got it started with the fluid we drove it around for a bit and it did fine. We will also look into the fuel filter, I believe the mechanics checked it out at the garage earlier… I will ask them.

Fuel delivery.

There may be a bad wire connection to the fuel injector if this engine only has one fuel injector. The cold may be enough to cause the connection to the injector to fail.

Ford has been all mult-port sequential for quite some time now.

The engine computer adjusts fuel flow (fuel injectors) and air flow (idle air control valve) according to the temperature. There are temperature sensors (coolant, intake air, battery) which feed to the engine computer. Some of the temperature sensors may be incorrect when it’s cold. They need their values measured when they are COLD, which is where they are when you are trying to start the engine. So, to check their values when they are WARM, which the shops MAY be doing (if at all) is not productive, nor revealing.

You would have thought that one of the 2 garages that this car has been to would have thought to change out the fuel filter. So today we took off the old one which looked to be the original filter put on the car, when we dumped the fuel out of the filter, it looked like mud coming out. So we put a new one on, so we shall see whether that has an impact on the starting.
Do garages assume that people who are not mechanics change out their fuel filters on a regular basis? Why would they not have thought to do that?

You would have thought that one of the 2 garages that this car has been to would have thought to change out the fuel filter. So today we took off the old one which looked to be the original filter put on the car, when we dumped the fuel out of the filter, it looked like mud coming out. So we put a new one on, so we shall see whether that has an impact on the starting.
Do garages assume that people who are not mechanics change out their fuel filters on a regular basis? Why would they not have thought to do that?