Question about 2001 GMC Yukon XL

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Low end power issues. Better @ 2000+ but never 100% gone.

Fuel pressure at port above engine is 32 when turning to ACC and running. I am told it should be 58-62. I am having low end power issues when taking off. Power slowly returns around 2000-3000rpms but never comes back 100%. I have changed the fuel filter, spark plugs, and spark plugs wires. I also cleaned the air filter. Told it could be PCM, positioning sensor, and fuel pump. Why fuel pump? I have fuel pressure (granted it is low) and truck runs. How PCM? I am not maxing the system out for it to blow by the relief. How positioning sensor? Truck doesn't stall and only has issues on acceleration from stop.

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I'm surprised it even starts, fuel pressure is vital for proper atomisation of fuel, i would start there

Posted on May 26, 2010

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Regards.

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