QuestionQUESTION: Hey guys, my 1500 HD died twice today. The DTC codes were as follows, p0174(fuel trim sytem lean)p0300(engine misfire detected)p0336(crankshaft position sensor performance) and p1514(throttle body performance). I wait 2 minutes, crank the truck up and it runs perfect. then it will do it again in 5 minutes or less. I have 174,000 miles on this jewel. I wonder which way to go at it after reading a bunch of different blogs? Any help on this would be greatly apprecitaed.
ANSWER: Hey Carlos,
What year and engine displacement? Pull the gas cap off and see if you hear a big hiss in the tank right after it quits.
Hooking a fuel pressure gauge up to the fuel rail will eliminate that whole circuit while diagnosing. Depending on the year of the vehicle fuel pressure could be 9-13psi 36psi or a minimum of 55psi. You need to find out if you are running out of fuel or spark.
Wayne
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QUESTION: Hey Wayne, thank you for the response. The truck is a 2003 6.0 litre, 174,000 miles. Also the coolant level has been low and I need to change the oil according to the message board on the instrument cluster. I may still be low on coolant level.thanks.
ANSWER: Hey,
I think we should check your code reference. To my knowledge a P1514 is a MAFF code. This sensor is responsible for fuel pulse width and ignition timing management in a huge way. Pull the air box out and make sure the grid isnt melted.
Wayne
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QUESTION: Thanks Wayne, I didn't get to see your response until this morning. I replaced the fuel filter when I got home yesterday. All seemed well, drove around 50 miles, no problem. Drove another 25 miles to work this morning, 3 miles before I got to work, she died again. Waited 15 seconds, cranked up drove to work. Checked the dtc's snd got the P0336 code(crankshaft position sensor),this is twice that I get this guy. I will go check the MAPP grid here shortly. Where is CPS and should I maybe go this direction, and swap it out?
AnswerHey,
It just dawned on me that I have had a few of those in the past and a crank relearn may be required. The TECH2 (GM Factory Scan tool) and some aftermarket tools have the ability to do a Crankshaft relearn procedure. The local dealer or someone with a TECH2 may not charge much for this procedure. You basically hook up the tool, access the CRl menu and perform the relearn by matting it while the tool is on.
The Crank Sensor is inside the distributor
Wayne
