Car wont start Frist try -- Many things already replaced

ford
explorer
repairs

#1

I have a 2003 Ford Explorer Limited V6 Non flex fuel. 1st symptom was, when the temp went down the harder the car was to start (start as in, turn key, battery comes on, it turns as in cranking, just wont catch). It would take 3 - 25 million times to start. If the temp was below 32 it would not start at all, over 75 only took twice. Once the car started, it would stall out. After that, it ran great, no other issues started frist time, until the engine got cold again. Had it diagnosed, the mechanic said, it was the fuel pump, it was to weak to build up the pressure needed when it was cold, so it had to build it up and that is why it ran great. Once pressure was gone, was when I had trouble again. Vacuum lines were checked no issues.

Had changed, fuel filer, fuel pump, spark plugs and wires, battery and MAF sensor. Fuel pump was the last thing to get changed out. With the other things listed, it did not improve.

After the fuel pump (last thing installed) was installed it wont start 1st time, (as in it cranks over, but wont catch). Second time starts right up. No more stalling. Now the 1st no start is consistent. I can run it for a half an hour, pump gas and it wont start 1st try. 2nd try no issue.

I have tried turning the key on to let the pressure build and try starting, Nope. Has to have the key turned off again and try to start again. No more stalling issues.

Any idea what this could be. I am mad at my mechanic right now (don’t want to go into how they wanted me to drive it back to the shop, and made me pay for a fill up afterwards, and more). After I picked up my car. It was reading 0 miles to E, on the tank. I went to the gas station to fill up… Splash, the gas went right out again… I was told it was “Simple Human Error”. The mechanic got called away and forgot to attach the fuel line, before he reattached it.

Could this "Simple Human Error’ incident caused any issues to fuel pump. They want me to pay another diagnostic fee to further see what the issue is. Could it be the fuel relay sensor (it did click when my husband checked) or the Main relay? Or something larger.
Thanks


#2

Fuel pressure regulator would be my first guess.


#3

So, now: Turn on key for 2 sec to let pressure build…turn off for 2 sec…turn on for 2 sec again…then start, and now it starts every time? at all temperatures?


#4

All temps on the gauges are fine. Yes, either turning the key twice it will start or if I start it once, and then try to start it again it will start. If I turn the key only once and then try to start it wont start… When starting the car makes all the same sounds as starting, it just wont catch. Since the fuel pump has been replaced it has been better. When they ran the diagnostics they said everything checked out fine, temp was reading good, fuel pressure was good, etc… My husband is thinking maybe starter since I went over a month with the hard starts (2 - 25 millions times, trying to get it to start, for it to quit and restart again). Thanks


#5

Obviously, there’s your “work-around” for now. You’re driving an aging vehicle. You could possibly use this method for years…

I believe you have a “fuel pressure sensor”…this might need replacing (a pure guess.)

;-]


#6

hmm … good ideas above, here’s what I’m thinking beyond all that. When the engine is cold, for it to start right up it has to have quite a bit of gas injected at first. A lot more than normal. And there’s no way for the engine to know not enough is being injected as the feedback system from the o2 sensor hasn’t come on line at that point. Any less fuel than it needs to pop and fire will show up much more when the engine is cold than warm. The amount of fuel injected depends on the fuel pressure, the function of the injectors compared to spec (when new), and the time duration of the injector pulses from the computer. Unlikely to be the latter, so here’s where I’d look

  • fuel pressure, make sure that measures according to spec, both from the pump, and at the fuel rail. measure when this problem is happening.
  • injectors are clogged. try an injector cleaner product in the gas tank, could help.
  • computer doesn’t realize how cold the engine is, so check the accuracy of the engine coolant temp sensor

Still no luck? Low engine compression has this symptom, starts ok warm, but not cold. So measure that. And the relationship with the ignition switch could mean that part is faulty. When you turn it, there’s several contacts that are made simultaneously. Done that way in part to make it hard to steal the car without the key. But if one of those contacts aren’t reliable, even if the others are, this can be the result. An auto-electric specialist mechanic w/Ford experience could test for that. For example, it might be the fuel pump power and fuel pressure is ok but the ignition system or fuel injection system isn’t being power up sometimes, b/c of a faulty ignition switch…

Seems unlikely to be the starter even tho it’s probably a little worn out. But as long as it makes that rr rr rrr sound during cranking more or less as robustly as when it started ok, I’d discount the faulty starter idea.


#7

Fuel pressure regulator is part of the fuel pump assembly in the fuel tank. If the fuel pump assembly was replaced, the regulator was, too.


#8

Thank you. I have put in a fuel injector cleaner. The guys at an auto shop, told me to try this (barryman b12). One thinks it might be the fuel injectors. When my fuel filter (sorry should have added this detail in), one side was completely clogged. This morning, it took me 6 tries to get the car started (it was 39 degrees outside). Now it warm, it is taking me 2 tries. Before (as in before new fuel pump) at 39 degree’s I was not guaranteed that it would not start at all. Even after 10 minutes. So this is an improvement, but now it has a hard start all the time (before it was the 1st initial start). To the poster before: Accepting this as an older vehicle issue is not okay with me and I don’t want to have a work around. This is our family auto, and I live in an area with 10 + lanes of highway. If my care decides to fail to keep on running, this could be life or death for my family on highways of 75 mph in 5 lanes of one way traffic. I can not risk the chance of loss of power. If I was young or my children were grown, I would totally agree with you. I do have a crack in my engine coolant temp housing (was told this during my oil change). Thanks for everyones help


#9

I think you are going to have to have a fuel pressure test done. Ideally, you could have a gauge installed temporarily and watch it every morning at first starting attempt. But, I realize you need your car, and can’t just sit in the driveway with the hood up. I don’t know if you can find a good mechanic and inform him of the details regarding temperature, so he can try and duplicate, but you may need to leave it with him for a few days.


#10

Thanks. I mechanic did so a diagnostic on it and said there was low fuel pressure from the pump, which lead to the fuel pump to be replaced. They said there was no codes, no vaccum leaks, all temps and gauges were fine. They had it for 2 days trying out different theories, and came to that. They explained that it took those many key turns to build up the pressure. And once the pressure was up this is why I didn’t have any issues afterwards until many hours later. The fuel pump didn’t fix the issue and now if feel the car is running rough. Thanks


#11

I meant you are going to have to have it done again. The previous test supposedly found a weak/bad fuel pump, and you said it improved. But now (I assume a couple weeks later?), you are having a problem, correct? It could be a defective new pump-yes, it can happen-could be fuel leak down, could be a lot of things, but no way to know without a test.