2005 Windstar won't hold a start

ford
van

#1

5 Ford Windstar. For the last year or so it has had an occasional problem where it will not be able to “hold” a start. That is, it will turn over and start as normal but will falter and die w/in a few seconds.



I have entertained a few different theories.



The first was that it was connected to how much fuel I had. That is; it appeared to happen when I was below 1/4 tank.

On a handful of occasions I was able to restart the vehicle after substantially filling the car via five-gallon jugs.



However that remedy has been proven unsuccessful at least once, most notoriously.



On this occasion, the most difficult incidence of this phenomenon, the refill method totally let me down. The car was above 1/2 when it failed and I filled the tank to the brim and it still would not start, even after several hours.



I was about thirty miles from home, had my two year old with me and had to wait several hours for the tow truck. This was a major drag.



I had the vehicle towed to my mechanic. Naturally, the van started right up for him (this was the next day) and he could not recreate the stall. He worked at it for much of the next day and could not get it to happen. Nor did any of his diagnostic tools reveal reason for the malfunction.



A second theory was that the car benefited from different fuel additives; STP gas treatment, injector cleaners and dry gas have become part of routine. I add something probably every other fill up.



My mechanic and I have discussed injector cleanouts, fuel pump replacements etc but he is confident in none of these remedies.



All of my theories have suffered from confounding variables, instances when the car won’t hold its start even when I thought everything was covered.



Recently I have found that just the act of waiting, seems to allow the van to start. I have to give it about fifteen- twenty minutes, but lately it has proved able to hold its start after such a duration.



I now think that the problem is most likely to happen when I am on a short trip when the car neither travels very far nor is expected to be turned off very long.



For instance two nights ago I went to pick up a pizza. I travelled just about a mile, turned the car off, ran into the shop, picked up my pizza and the van did its thing. However after a brief wait (I think it was a one beer wait at the local tappy) I was able to go home.



Thoughts


#2

If the engine cranks, but won’t start, then either it is not getting fuel or not getting a spark. Your description that it will “start as normal, but falter and die” suggests a fuel problem. When this happens, if you could give it a shot of starting fluid, this would give some information. If it runs for a few seconds, you have a fuel problem. If it doesn’t fire up, then you need to test for spark. If there is no spark, then you need to be looking at the ignition system.


#3

Both the crank position sensor and fuel seem reasonable answers. The fact that sometimes you can cure the problem by filling the tank makes me think you have a weak fuel pump, so that filling up the tank gives you more fuel pressure. But it’s clearly an intermittent problem. You could get the fuel pump pressure tested, or just replace it.


#4

Have you ever tried giving it a little “gas” when it won’t start? These days giving it “gas” (stepping on the accelerator) is really giving it air (the computer does the gas). Lots of Ford models have had issues with idle air control (IAC) valves which is what is responsible for giving the car enough air at idle. I don’t know if this is one of them or not. Holding the accelerator would allow some air though the throttle.

Presumably your mechanic has checked the fuel pressure and found it to be within specs? And presumably the pressure was observed during a cold start? If not, it should be.