2003 Chevy Silverado 2500hd
Thread Starter
Member
Posts like a V-Tak
Joined: Sep 2018
Posts: 30
Likes: 0
From: Buffalo
Member
Posts like a V-Tak
Joined: Nov 2017
Posts: 45
Likes: 2
It is a possibility. Check what was said earlier and hopefully you will find the issue. I would check injector harness first. There is something causing the multiple misfires. Do you have a live scanner if so you can see which ones are acting up and it will give you a place to start. Make sure you check the harness real good.
Senior Member
True Car Nut
Joined: Feb 2015
Posts: 6,851
Likes: 1,015
From: Earth
Random misfire detected. Common with UIM gaskets gone bad. They lose elasticity as they get old and don't seal all the way. The little bit of extra air at idle is a big deal, but at speed is not.
Later on these. Should figure out the misfire first.
Later on these. Should figure out the misfire first.
Last edited by CathedralCub; Sep 11, 2018 at 12:27 AM.
Thread Starter
Member
Posts like a V-Tak
Joined: Sep 2018
Posts: 30
Likes: 0
From: Buffalo
Is there a way to see if the intake manifold is leaking without taking everything thing apart?
Senior Member
True Car Nut
Joined: Feb 2015
Posts: 6,851
Likes: 1,015
From: Earth
Regardless, 110,000 miles on a 2003 4.8/5.3/6.0 almost guarantees it needs upper intake manifold gaskets replaced, so the way I see it you could:
1. attempt to find the cause of this issue elsewhere and maybe find something after beating your head on it enough, then end up needing UIM gaskets anyways in the next few months as the weather gets colder (yes, cold makes the symptoms of a UIM gasket failure worse).
. . . or . . .
2. swap out the UIM gaskets now, and in the unlikely chance that the problem continues you will have ruled UIM gaskets out as a factor and can keep searching knowing that they are good.
. . . and now that I think about it there'* a:
3. Keep living with the issue and see what happens as the weather gets colder. If the issue gets worse then it'* more likely UIM gaskets that need replaced.
A question: What part of the world does this car live in?
Last edited by CathedralCub; Sep 11, 2018 at 01:29 PM.
Thread Starter
Member
Posts like a V-Tak
Joined: Sep 2018
Posts: 30
Likes: 0
From: Buffalo
You can try spraying carb cleaner around the gasket while it is running and see if that changes the engine idle speed. That gives you probably a 30% chance of finding a leak. Often the leak is on the inward-facing edge of the gasket where you can't spray without taking it apart.
Regardless, 110,000 miles on a 2003 4.8/5.3/6.0 almost guarantees it needs upper intake manifold gaskets replaced, so the way I see it you could:
1. attempt to find the cause of this issue elsewhere and maybe find something after beating your head on it enough, then end up needing UIM gaskets anyways in the next few months as the weather gets colder (yes, cold makes the symptoms of a UIM gasket failure worse).
. . . or . . .
2. swap out the UIM gaskets now, and in the unlikely chance that the problem continues you will have ruled UIM gaskets out as a factor and can keep searching knowing that they are good.
. . . and now that I think about it there'* a:
3. Keep living with the issue and see what happens as the weather gets colder. If the issue gets worse then it'* more likely UIM gaskets that need replaced.
A question: What part of the world does this car live in?
Regardless, 110,000 miles on a 2003 4.8/5.3/6.0 almost guarantees it needs upper intake manifold gaskets replaced, so the way I see it you could:
1. attempt to find the cause of this issue elsewhere and maybe find something after beating your head on it enough, then end up needing UIM gaskets anyways in the next few months as the weather gets colder (yes, cold makes the symptoms of a UIM gasket failure worse).
. . . or . . .
2. swap out the UIM gaskets now, and in the unlikely chance that the problem continues you will have ruled UIM gaskets out as a factor and can keep searching knowing that they are good.
. . . and now that I think about it there'* a:
3. Keep living with the issue and see what happens as the weather gets colder. If the issue gets worse then it'* more likely UIM gaskets that need replaced.
A question: What part of the world does this car live in?
Senior Member
True Car Nut
Joined: Feb 2015
Posts: 6,851
Likes: 1,015
From: Earth
Okay so not like Texas or Florida or Arizona where it really doesn't get cold. If it is UIM gaskets then the upcoming cold weather will affect them more.
Thread Starter
Member
Posts like a V-Tak
Joined: Sep 2018
Posts: 30
Likes: 0
From: Buffalo