Long crank 5.4 2v
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Joined: Jul 2021
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Long crank 5.4 2v
Hey guys, so I have a 2001 Ford expo with a 5.4 4x4, when I let it sit overnight on the cold start it takes around 5 seconds to turn on before it would only take a flick on the key, it was one day to the next that this problem popped up, I’ve replaced spark plugs original motocraft gapped perfectly, ignition boots and springs, fuel pump and filter and have the same symptoms, I have notice that it’s slightly sluggish than normal and my avg mpg on the overhead console is around 9 mpg used to be around 12.8, driving conditions haven’t changed in the past year, one thing to note is also only on cold starts my oil press guage doesn’t go up, all the time sometimes it goes up or sometimes it takes a few seconds around 5-10 sec, but I’ve checked pressure mechanically and all is good, could it be the oil pressure sensor? I was thinking about ignition coils also maybe one or two are weak?
Fleet Mechanic
Joined: Aug 2004
Posts: 1,276
Likes: 7
From: NE Tennessee
If a coil was weak you would have a miss and eventually when enough misfires a code pop up. You can check with a reader to see if any codes are pending as it may not be bad enough to trigger but that much of a mpg lose that would be quite the miss. Have you checked fuel pressure with a gauge to make sure the 'new' pump hasn't gone bad or is weak.
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Joined: Aug 2003
Posts: 25,479
Likes: 742
From: Isanti, MN
It really sounds to me like a fuel delivery issue, especially since it’s sluggish during regular driving. The oil pressure “gauge” is a glorified idiot light; these engines don’t have a sensor for the oil pressure. It’s a simple switch that’s either closed or open, and the PCM doesn’t shut things down when it’s open. So that can’t be it.
What’s your cranking fuel pressure?
What’s your cranking fuel pressure?
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