× Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!

1999 silverado 5.3 5 volt circuit short

More
10 Jun 2019 16:00 #30576 by Ljs
I have a 99 5.3 silverado with a 50k engine in it, I've been constantly looking for a 5 volt short, truck runs ok with a low level random misfire, the only indication is a fuel tank pressure sensor circuit code, it's not there tho, it's somewhere else, please advise,

Please Log in or Create an account to join the conversation.

More
11 Jun 2019 15:27 #30597 by chief eaglebear
Replied by chief eaglebear on topic 1999 silverado 5.3 5 volt circuit short
hi sir can you put upa diagram - do you have a 5 vref established if your trying to find short that may be difficult ona 5 vref circuit but its possible im not sure the fuel pump uses 5 volt ref line

Please Log in or Create an account to join the conversation.

More
11 Jun 2019 15:30 #30598 by chief eaglebear
Replied by chief eaglebear on topic 1999 silverado 5.3 5 volt circuit short
with an intermittent short on 5vref line the truck may cut out if its loosing crank signal maybe scope your crank signal if you have scope -

Please Log in or Create an account to join the conversation.

  • John Curtis
  • Away
  • Premium Member
  • Premium Member
More
11 Jun 2019 18:05 - 11 Jun 2019 18:10 #30604 by John Curtis
Replied by John Curtis on topic 1999 silverado 5.3 5 volt circuit short
What checks have you done?
Is there a particular reason you’re concerned with reference voltage?
If you’re having a misfire you probably want to run through the basics first.

Fuel
Air
Spark
Timing
Exhaust
Compression.

Probably not in that order.
Is it a random misfire?
Is it one particular cylinder?
What are your fuel trims and 02s telling you?

Thinking out loud always helps me in the process.
Last edit: 11 Jun 2019 18:10 by John Curtis.

Please Log in or Create an account to join the conversation.

  • Not Allowed: to create new topic.
  • Not Allowed: to reply.
  • Not Allowed: to add attachements.
  • Not Allowed: to edit your message.
Time to create page: 0.520 seconds