GMC Troubleshooting Questions? Ask a Mechanic for Answers
Hello, my name is ***** ***** I am a professional here at Just Answer. I have noticed that your question was not getting a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.Can you please explain what you mean when you say its spilling back ? Also if you connect a volt meter to the battery with the engine running what is the voltage reading. If possible can you also scan the computer system and see if there are any fault codes setting. Post back with the results when you can and we can work from there.
Your charging voltage is fairly close as long as it not going any higher, the normal charge rate is usually not much higher then 14.2 volts so you are a bit on the high side. Spitting through the intake usually indicates a valve timing concern. Are you able to place a timing light on the engine while the problem is occurring and monitor the timing?
Okay then let start with having a a look at the timing to see if its holding steady.
No problem, Im here all day.
So when do you hear the popping through the intake? Dose it happen under load?
If the timing is holding steady the I would start next with monitoring the fuel pressure to make sure the fuel pump is holding proper pressure. Normal pressure on your 5.7 should be right at 10 14 PSI. Anything less then 10 PSI would indicate a failing fuel pump or restricted fuel filter.
Okay then install a fuel pressure gauge and monitor the fuel pressure while the problem is occurring.
Was it spitting once the alternator stopped charging. Did you address the no charge problem?
Are you sure that circuit is not shorting out. Somethings not making sense here.
I would start with checking the brown wire. Which brown wire are you unhooking?
Okay there has to be some issue with this wire or the circuits it controls if the truck runs okay with it disconnected. That the circuit you are going to need to check.
Okay, Im off this morning but will try and check in this afternoon. Good luck on the hunt.
The code 43 can be set due to any of the following,
Glad to hear you got it resolved. Good work. Thank you as well.
Your very welcome and that you as well. Please take a moment to rate my service so I can get credit for my time, the question remains open for follow up even after doing so, all you need to do is return to this question if need be.Thank you again.