Delay between engine cranking and truck turning over

My truck recently started having an issue when it hasn’t been run for a few hours/overnight. I’ll turn my key in the ignition and the truck will crank for a normal amount of time. When it’s done cranking, there is a second or so delay before the engine actually comes up to speed.

Most of the time, it’s just a one second delay. A few times, when it was colder out it would go through that cycle a few times where it would struggle to start up. It didn’t require me to crank it again, the engine just seemed to go through multiple cycles of trying to start up.

Would love any insight anyone may have into the issue. Thanks!

What year, mileage, engine, and transmission?

The next time you go to start the engine after it’s sat, turn the ignition on so the dash lights turn on for two seconds, and then turn the ignition off.

Repeat this a half dozen times and then try starting the engine.

If the engines starts right up, the anti-drain back valve on the fuel pump is leaking.

Tester

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It’s a 2012 Chevy Silverado 1500 with 136K miles on it. 4.8L 8 cylinder engine.

Its an 11 year old Chevy 1/2 ton with 136k, it is highly likely to be the fuel pump. And while this is simply a small bit annoying, that pump is close to replacement anyway.

My 2004 Chevy’s pump rusted out at that mileage.

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OP, you can always ask your shop to measure the fuel rail pressure. Called a fuel pressure hold test. If pressure doesn’t hold to spec’s psi for a certain amount of time after turning off engine, you’ll know for sure. The symptoms do sound like it is a low fuel pressure problem on re-start.

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It’s called a residual fuel pressure test.

Why pay a shop to do a residual fuel pressure test when the key dance tells you the same thing?

Tester

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Replacing a fuel pump based on a key-dance experiment, pretty good chance of success. No complaint. But a fuel pressure hold test provides how quickly the fuel pressure drops, and that could possibly provide a clue the problem is not the fuel pump. OP might find the following vdo helpful.

George doesn’t understand that all we’re tying to do here is determine if the starting problem is due to a leaking anti-drain back valve at the fuel pump.

And the key dance has been the most common procedure used by DIY’ers since the introduction of fuel injection.

So, do the key dance. And if doesn’t show an improvement on the engine starting, then bring it to a shop so they can do diagnostics to determine what the actual problem is.

Tester

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I agree, I have told many a customer to do the key dance at home or where ever before bringing it in for a diagnostic…

What do you folks do next, if the key dance improves or eliminates the symptom?

The issue was my fuel alcohol content impacting my long term fuel trims. I had watched a couple of youtube videos on this and suspected it might be the issue but didn’t have a scanner to reset them. I went to oriley’s and saw my LT fuel trims were out of whack and my fuel alcohol content was ~50%. Had a mechanic reset the fuel alcohol content and fuel trims and it starts up as it used to.

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I just remember that the key dance works, and do it on the rare occasions when my Honda has a crank-but-no-start issue. A near-empty tank and/or a drop in ambient temp may be a factor.

No doubt sometimes the key dance works, at least short-term to get the car to start. Just wondering what the pro-mechanics suggest that car owners do once they discover that the key dance gets the car started? Is the recommendation to still take the car to the shop? If so, that is the same recommendation if the key dance doesn’t work. Seems simpler then to forget the key-dance entirely, and just recommend to take the car to the shop when it won’t start.