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Car occasionally will not start

So, you found something which looks like mud in the fuel filter, which looks to be the original filter? Yes, I think you have found the problem.
Why don’t some shops/mechanics do the simple stuff, like measure fuel pressure and change fuel filters? The possibilities are limitless; but, it does show that there are more than enough “inexpert” mechanics/shops.
Let us know if it’s all fixed, now.

I will let you know. I guess time will tell. We have started it about 3 times today successfully. I will feel better if after a couple weeks it starts up consistently. Also we have some really cold days coming up so that too will be a test.
Thanks for all your help!

Well, this morning it would not start on it’s own again. It started after we sprayed with the started fluid and will quite likely run the rest of the day fine. I was hoping for a better result. Do you think it has to work out the junk that was in the lines. We are starting to think that we are just going to pull off the gas tank and possibly put in a new fuel pump. Any thoughts?

The trouble may be with the fuel pump. The trouble may be with a check valve in the fuel pump that is allowing fuel to slowly flow back into the tank. Try turning the key from off to on several times and allow the pump to charge the line. If that is the trouble the engine should start ok then and you have pinned the trouble down.

We have done that on several occasions and after turning the key to charge the line, it still does not start. The only thing that will start the engine when it’s down is to use the starting fuel spray.

When it doesn’t want to start is the temperature outside cold? I seem to notice a pattern of when the vehicle is inside and warmer it starts, which makes me think it may be something as simple as a bad coolant temp sensor. Cold conditions require more fuel to crank the engine. if the computer isn’t seeing a correct temperature when the ambient temps are cold it won’t deliver enough fuel which can cause a rough idle or a no start condition. the only way to be sure is to take it to a shop and have them check it on a cold morning OUTSIDE.

Although you have a different make and model…this happened to my brothers mazda. This will sound strange but the problem was that “on occasion” water would drip onto the alternator from a cracked water pump hose shorting out the electrical system and either shut off the car or not allow it to start!!! Strange but true!! good luck!!

After replacing the dirty fuel filter, still same problem. Weather it’s the ambient cold temps. or the car just sitting for 12 to 15 hours when it’s not so cold outside, still won’t start without spraying starting fluid into air intake. While engine light is currently not on, I borrowed an error code reader and got these codes:
P0303 - cylinder 3 misfire detected
P0316 - misfire detected 1st 1000 revs.
also got pending codes
P0171 - system too lean bank 1
P0174 - system too lean bank 2
Any ideas appreciated!

Also the original garage did check the fuel pressure and they said it was good.

I think those mechanics WON’T / DON’T KNOW HOW to properly measure the fuel pressure in the cold (outside). Also, ditto for checking the temperature sensors (voltages and ohms) under real conditions (outside, in the cold).
You might be ahead of the eight ball if you, preemptively, have the engine coolant temperature sensor changed. It’s, relatively, cheap.

Is that something we can do ourselves, or will we have to take it to a garage? (hopefully not a garage)

You can measure the voltage and resistance of the temperature sensor and also change it yourself if you need to. Be aware that the sensor is most likely not the same one that ties to your dash temperature gauge which most likely only has a single lead tied to it. The one you want may have two leads going to it. I’m not familiar with your model. I’m just going by what others use.

If you monitor the voltage you are looking for a change in voltage as the engine warms up from a cold start. A good sensor will show a change with the temperature. It may be more voltage or possibly less, depending on the circuit design.

Since it appears that the fuel isn’t back flowing into the tank another possible trouble area may be the fuel pressure regulator.

If you don’t have a factory service manual already I suggest you get one so you can refer to it for this trouble. They are so valueable to have for troubles like this. Ebay is a good source for them and at a good price. Here is a good deal; the best money you can spend on the car. To me, just the wiring manual alone would be worth the price since wiring problems are so common and there is nothing better than the factory manual to have as a reference.

We did purchase the Haynes repair manual for the car. We will look into the temp sensor and the fuel pressure regulator as you mentioned.

I have exactly the same problem with my Ford Windstar. It won’t start (or starts rough) during cold weather. The problem resides in a faulty “throttle bypass valve” (part costs about $100) that gets stuck when its cold. However, if I tap the valve lightly with a hammer, the engine starts immediately. I live in Texas and this year has been colder than normal, so the tapping procedure has become a daily routine in the morning and sometimes after work. The dealer wants to charge me $350 to replace the valve ($250 in labor!), which I find excessive. In the meantime, I carry the little hammer with me.

We will certainly try that as well, cant hurt. But this problem seems to get stranger day by day. Thursday the car had to be started with the starter fluid because it wouldn’t start on it’s own, Friday the car wasn’t driven at all or even started, the weather began to get really cold here about then too. So Saturday afternoon about 5PM we were going to have to drive the car, it was the coldest day so far this winter and it started right up without the starter fluid and was driven back about midnight just fine. I just don’t get it.

Rather than just replacing the “throttle bypass valve” (aka idle air control valve) you may have success by pulling it off and cleaning it. Just use something like a throttle body cleaner. You’ll want to have a new gasket for it handy. Clean the electrical connections (electronics cleaner) while you’re at it and give them a coat of dialectric grease. This should all amount to about 6 bucks and 30 minutes of time.

First… thanks so much for your help up to now!!!
Well, we finally decided to just trade cars with our son (who lives in another state) so that he could have reliable transportation while job hunting and we try and sort this out. Up to this point my wife has been trying to articulate what has been happening with this car. I wanted to take some pressure off her and take over. Like that’ll help! hah.
Here goes…
2004 Ford Taurus SES - 3.0 V6 - VIN 1FAFP55U34A135381
8 months ago, a valve “broke” and blew the engine (according to my mechanic) . We figured since the car was long paid for and wanted to keep it, we had them put another engine in it (used one with apx. 50,000 mi.)… everything seemed good and off we went. Then… a few months ago the transmission went out. Same decision, re-build it, all new parts, great! Off we went. Then one day my son took it to Valvoline Instant Oil Change… great (he’s always been good about changing oil in timely manner on his vehicles). The next morning is when the trouble began. It would not start. I don’t see how this could have anyhting to do with Valvoline, but who knows. It would crank all day (in fact we killed the battery doing so), but would not start. Now ee can usually get it started with starting fluid (removing air intake hose and spraying directly in) Since then we have done these things:
Replaced the battery
Replaced the serpentine belt
Replaced the fuel filter -twice- (which first time was full of gunk/grit)
Replaced the fuel pump (complete assembly)
Replaced the fuel pump relay
Cleaned out dust/dirt particles from air filter compartment (replaced air filter)
At this point… it still doesn’t want to start on cold mornings OR after it has sat for a day or two whether its cold outside or not. Just did it this morning, and although it hasn’t been terribly cold here in Nashville, the car did sit for about 24 hours. I used the starting fluid and got it started… once it smooths out (10 seconds or so), it runs as smooth as silk. Funny thing… as soon as the key is turned to start, the car WANTS to start, immediately starts to run, but even when it does, it runs rough for a few seconds before smoothing out. You have to gently pump the gas pedal during this time to keep it running until it smooths out. Also during this phase, there appears to be a bit of grey smoke our the tail pipe. After it smooths out, you know you’re safe to drive the rest of the day, because it always starts the second time once it has smoothed out and warms up.
H E L P ! please.

“It, sometimes, needs starting fluid to get the engine started in the cold, and it helps to to keep the engine stumbling along by playing the throttle, until the engine rpm stabilizes. Occasionally, there is some gray exhaust.” These are the basic symptoms?
The engine might be be burning some oil. Check some of the spark plugs for fouling.
Did you remove the idle air control valve (iacv) and clean its pintle? Did you clean the air passages to and from the iacv? Have you used a Throttle Body Cleaner to clean the throttle bore and throttle plate? While you’re in the air intake, use MAF Cleaner to clean the MAF (Mass Air Flow) sensor.
Can you ever hear the fuel pump running? Turn the ignition key to RUN. The fuel pump should run for two seconds. Can you hear it?
When it doesn’t start, put a fuel pressure gauge on it. What is the fuel pressure, at that time? Beginning with the first key to RUN, the fuel pressure should go to about 15 psi. Key OFF, and back to RUN, and the fuel pressure should go to about 30 psi. Third time, key OFF, and back to RUN, and the fuel pressure should be about 45 psi, or higher. Without the engine running, the fuel pressure should hold for several minuets. I’ve seen it hold for HOURS.

I fully agree with Hellokit here but will add one thought.

If that much mud (crud?) came out of the filter, I wonder what condition the bottom of the tank is in?