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Clayso, Master Automobile Technician
Category: Dodge
Satisfied Customers: 880
Experience:  ASE Master Certified Automobile Technician. 30 Years Experience.
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2005 5.7 truck 1500 , the engne light has been on weeks

Customer Question

2005 5.7 truck 1500 , the engne light has been on for 3 weeks disconnected battery 4-5 different times light wont go out code p300 shows random miss. truck has been running fine up until a few days ago and now it hesitates from a dead stop put in 2 bottles of heet gas additive and it has helped a little
Submitted: 2 years ago.
Category: Dodge
Expert:  Clayso replied 2 years ago.
Hi There, I'm Clayso a certified master automobile technician with 30 years of automotive repair and diagnostic experience. From your description I would say p300 should have been P0300. P0300 sets when Multiple Cylinder Misfires are detected. The most common cause for P0300 is broken or weak valve springs. Connect a vacuum gauge to an engine vacuum port below the throttle body. If the needle is bouncing and erratic, check for broken valve springs. Another common problem is fuel pressure, have the vehicles fuel pressure checked, if it's below 58 psi. suspect a weak fuel pump. Other possible causes are listed below. Possible CausesASD relay output circuit.Injector control circuit.Coil control circuit.Ignition wire.Spark plug.Ignition coil.Fuel pump inlet strainer plugged.Restricted fuel supply line.Fuel pump module.Fuel pressure leak down.Fuel injector.Engine mechanical.PCM. I hope this information is helpful to you. Should you have any questions please let me know.Kindly rate my assistance in a positive manner so I may have credit for helping you. Positive ratings are greatly appreciated.Thanks so much.