No start then start condition

[SierraK1500]

Girlfriend has a 2005 GT over 100K on the clock. When the car is cold or has been sitting engine will crank like crazy. No start. Leave the car ignition on for a few seconds more and ZOOM she fires right up and will start evey time there after.

I feel a fuel problem. Possible clogged filter? Fuel pump in the tank going south? Or surprise me with a bad ignition.

Please help on this one?

Many thanks!

John

[xeroinfinity]

It could be a fuel issue. Though I'd check that the battery terminals are clean & tight. And that it has 12.4+ volts.

Check the fuel pressure with key "on", should be 41-48 PSI.

Could be the spark plugs are bad/fouled out , or just needing a tune up.
Could also be a vacum leak on the lower intake, or some other emission control.

Hope that helps and sorry for the delayed reply !

[SierraK1500]

Thank you zeroinfinity. You most likely confirmed my suspicions.

The car is going in for service. Will post a result here.

John

[SierraK1500]

Well heres the latest on the no-start condition.

First off the regulator valve going to the injector rail was leaking at the seam.
That was replaced as it was a fire waiting to happen.

The cranksensor went bad. Didn't supply a pulse to the ignition. We got the car started and drive it to the mechanic about 25 miles away. She failed to start.

Funny this didn't have an error code to be read on the computer.

Anyhooo this car is running now.

Thank you Xeroinfinite for your help and suggestions.

It is sincerely appreciated

John

[motorzonesuzuki]

hello, I have the same problem on my grand am, but I was wondering which crank sensor was bad, there is one behind the crank pulley, and one in the side of the motor.
Thanks,
Motorzonesuzuki

[3100]

CKP on the side of the engine is the most important sensor on the engine. If that one does not work you will not start. All other sensors can be substituted by PCM maps if they go bad.