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Ask George H. Your Own Question
George H.
George H., ASE Certified Technician
Category: GM
Satisfied Customers: 18668
Experience:  15+years ASE Master W/L1 Drivability
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My names is Ango. i have p1345 and knocking noise on my

Customer Question

Hi my names is Ango. i have p1345 and knocking noise on my gmc envoy 2002.
JA: Thanks. Can you give me any more details about your issue?
Customer: i´m not so good to english, but engine starts fine and idle is fine but if push my foot i can hear knocking sound from engine and engine code P1345 what is that?
JA: OK got it. Last thing — GM Mechanics generally expect a deposit of about $32 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: GM
Expert:  George H. replied 1 year ago.
Hello I will help you with your question, have you moved the distributor?
Customer: replied 1 year ago.
No i did nothing yet.
Expert:  George H. replied 1 year ago.
OK, the code means the sensor in the distributor and the one on the crankshaft are more than 2 degrees apart and they should be 0 or read the same. It sets the P1345 when they are more than 2. This could mean the crank sensor is damaged. Where do you hear the knocking from?
Customer: replied 1 year ago.
I'm not sure the noise is coming from, but it comes from the engine. Should i buy a new crank sensor? And what else?
Expert:  George H. replied 1 year ago.
Before you replace any parts check for the knocking noise. Can you make the noise without driving the vehicle.
Customer: replied 1 year ago.
Yes knocking noise comes when engine is running without driving vehicle, but not in idle, only if i accelerate
Expert:  George H. replied 1 year ago.
Then you need to isolate the noise. A paper towel center roll, a heater hose, a mechanics stethoscope all can be used to narrow it down. If the noise is a loose pulley or something with the distributor that may be why you have the code. If the distributor is out of position or worn it could be making the noise. In any case you are going to need a scantool to reset the distributor position. It must display the "cam/crank offset" in degrees to allow you to set the signal timing.
Customer: replied 1 year ago.
i can´t fine the distributor where is located? 2002 gmc envoy 4.2
Expert:  George H. replied 1 year ago.
I'm sorry you have no distributor on that engine, the cam sensor is lower front of the engine and the crank sensor is driver's rear in the side of the block. Check for the source of the noise, if it is up front it might be timing chain or cam phaser related.