Fuel Pump Relay issue...maybe?

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doncaruana

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After my warmup spin (ran a mile up and down the freeway, drove it about 10 minutes), I let it sit for an hour and went to start it. Long crank - not the full on "won't start" scenario but definitely longer than it should be. But it started and ran. So then I went out to lunch with my wife and came back about 2 hours later. Perfect start, very fast.

So far, it's smelling like the problem wasn't really resolved. Needs more testing of course.
 
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doncaruana

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My daughter has been ill so the truck hasn't been driven much. But now that we have a bit of a sample, the current issue is that almost every first start - cold or hot, is a long one. Not quite like before in that it typically will start. But you have to hold the key and crank it for a while. Second crank still is good though and maybe even a little better according to my daughter. And sometimes she doesn't hold it that long and then the second crank it's almost instantaneous.

So the first crank kind of got worse - it used to be good if it was cold at least, now it's a long crank close to, if not, every time. However it does usually start vs the reproducible fails when it had sat a bit after warming up. But the second crank, when done, is better.

The next thing I think I may have her try is to "double prime" the fuel pump before trying to crank it and see if that makes a difference.

I'm super pissed at the shop, who at the time told me if the new ECM didn't fix it they'd give me a refund. I suspect they will try and blame the programming, which is complete hogwash, because I paid half what they were going to charge me and had another company who does that for others shops do it for me. Or they will say it was part of the problem because the behavior changed.

But...given what I've said here, is it possible that there is some sort of adjustment that can or needs to be done? I mean I can't really explain the behavior change either. Before I talk to them again, I'd love any feedback or suggestions I can get. It does seem as if it got a little worse after it was programmed to the correct VIN.
 
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exp500

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Have you completed the Drive Cycle? Usually a mix Town /Hwy 50 miles minimum.
 
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doncaruana

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Yes, it's been driven a couple of hundred miles since the vin was programmed.
 
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doncaruana

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Should I do something like try disconnecting the battery for 10 minutes? Would that "reset" the ECM and make it relearn or something? I'm just SO frustrated with this. :(
 

exp500

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The relearn is complete by now.Don't disconnect For this. Any codes or misfires?
Now try cycling the key to on wait 2 seconds off on wait 2 seconds before starting. If that works every time, then we diagnose wiring to pump.
 
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doncaruana

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The relearn is complete by now.Don't disconnect For this. Any codes or misfires?
Now try cycling the key to on wait 2 seconds off on wait 2 seconds before starting. If that works every time, then we diagnose wiring to pump.
I disconnected for 15 minutes this morning. Oops. Either way, this morning started good. A little light on retry (thought it might stall) but didn't and started quick each time. Took it for about a 20 minute drive afterward. Ran fine - running has been good, just starting is an issue.

So you are saying put it in the start position (not cranking) for 2 seconds, then off for 2 seconds. Then do I go all the way to crank from there or put it in the start position for 2 seconds again first?
 
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doncaruana

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Went out and started it again after letting it sit for 3 hours, but did not do the double cycle. Long crank. I'll do the double cycle from here out. Just really smelling like the fuel pump still to me... Although I can't completely understand why the behavior changed.
 

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