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sonoma issues


pinhead0081
10-27-2009, 06:53 PM
i have a 2003 gmc sonoma that has 4.3 vortec with x code i cannot get it to start it turns over batt is good im getting spark from coil fuel pump is working wit 62 psi at fuel filter and im not sure what else to check any info would be greatly apreciated

MT-2500
10-28-2009, 09:06 AM
Is the spark getting to all spark plugs?
Dist rotor turning when cranking?

Will it start with a shot of carb cleaner?

If so you have a fuel delivery problem.
Fuel pressure or injector pulse.

Any check engine lights or codes or security lights staying on?

Are the spark plugs wet or dry on the ends?

pinhead0081
10-28-2009, 12:14 PM
all plugs firing will not start off carb cleaner and you can smell the gas and i have 62psi when i tested the fuel system

MT-2500
10-28-2009, 01:14 PM
all plugs firing will not start off carb cleaner and you can smell the gas and i have 62psi when i tested the fuel system

Are plugs wet or dry on ends after cranking.

What is cold cranking fuel pressure?
Should be up to 64-65 lbs.

Any codes or security lights on?
Good Injcctor pulse?
Remote starts or aftertmarket alarm systems?

pinhead0081
11-01-2009, 05:00 PM
replaced plugs distributer rotor and plu wires. now im getting a multi/random cylinder missfire reading code p0300

MT-2500
11-01-2009, 05:17 PM
I missed on fuel pressure it is 65/62 lbs.
Put a gauge on it and drive it 30 minutes and watch feel pressure.
post bback raedings.

Plugs good and AC delco?
Good hot blue spark to all plugs?

What is the camshaft retard readings?
MAF sensor good?
Try cleaning it with some sensor cleaner.

pinhead0081
11-01-2009, 05:25 PM
already cleanes maf sensor pressure is 63 to 64 how do i check the cam settings

MT-2500
11-02-2009, 05:11 PM
already cleanes maf sensor pressure is 63 to 64 how do i check the cam settings
Good AC delco plugs?
You need a engine capable scanner to check camshaft retard setting.
It should be 0 or +1 0r -1 degrees.

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