03 2500 6.0l

[Dieselfixer]

Hi All

A friend has a 2003 2500 Silverado with a 6.0 gas engine. The problem is that the engine has no power and will not rev up past 2000 rpm. We scanned it and no codes are present. I was thinking the cat was clogged and had him disconect the exhaust and try to rev it up. This made very little difference.

If he holds it to the floor it will rev up a little bit higher and the check engine light will come on but go off at idle. It gave a code of P300 after that. Any ideas?

 

Thanks Al

[cbxeric]

I have read that this can be caused by a bad MAF sensor.

[mooreapi]

dieselfixer,

do you know how many miles on it?

I've had similar experience with my 00 5.3l when either the fuel filter was clogged or the fuel pump was failing, seemed to fail about every 50-80K (now on pump #6).

I would recommend checking MAF (cleaning with MAF Cleaner (aerosol) might help), then replace fuel filter and check system pressure.

 

Matt

[Draenor]

dieselfixer,

do you know how many miles on it?

I've had similar experience with my 00 5.3l when either the fuel filter was clogged or the fuel pump was failing, seemed to fail about every 50-80K (now on pump #6).

I would recommend checking MAF (cleaning with MAF Cleaner (aerosol) might help), then replace fuel filter and check system pressure.

 

Matt

I agree Matt. Plus have the plugs/wires been changed?

[Schmids5.3l]

Hi All

A friend has a 2003 2500 Silverado with a 6.0 gas engine. The problem is that the engine has no power and will not rev up past 2000 rpm. We scanned it and no codes are present. I was thinking the cat was clogged and had him disconect the exhaust and try to rev it up. This made very little difference.

If he holds it to the floor it will rev up a little bit higher and the check engine light will come on but go off at idle. It gave a code of P300 after that. Any ideas?

 

Thanks Al

 

P0300 is a random multiple misfire code. Check plugs, wires, all ignition basically. Cats can also relate to this, bad O2 sensors. Disconnecting the exhaust completely throws off the rear o2 sensors so that won't help at all. Which cylinder(s) were misfiring? One here - one there, or a whole bank?? Check fuel injectors and fuel rails. If it's a whole bank than it should be easy to find the problem. The cat on the bank could be failing, the harness to the 4 coils on that bank could be failing, or the fuel rail on that bank could be failing. The Cam and or crank sensors could be failing too, as the crank sensor controls the timing and the cam sensor has a huge impact on fueling. If the crank sensor was dead the truck wouldn't start period, I believe if the cam sensor is failing the trucks fueling would run off the previous table prior to cam sensor failure, and probably wouldn't start after turned off. It sounds like his truck is running in limp-home mode.