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Rough Idle

FrankenChevy

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FrankenChevy Enthusiast

FrankenChevy

Posted
Posted

My 2001 Silverado has developed a rough idle. It feels like it is missing on one cylinder. I just changed the spark plugs, no change. I also just replaced the original battery.

 

I was thinking maybe a coil, or a fuel injector. I am not sure of the best way to troubleshoot.

 

It's a 2001 Silverado 5.3L auto trans. It's got about 110k miles on it.

 

 

Thanks

 

 

 

.

Carder09 Senior Enthusiast

Carder09

Posted
Posted

I kinda had the same issue but it only "studdered" every now and again. Good thing was it didn't affect any performance but I went ahead and changed all plugs and wires, both were due, and it turns out one of my spark plug wires was just sitting on a plug not fully compressed onto the spark plug. After all that, runs like new once more without any issues.

txab Senior Enthusiast

txab

Posted
Posted

Check for codes.

 

Clean MAF and throttle body

 

Fuel filter

Fuel pump pressure

FrankenChevy Enthusiast

FrankenChevy

Posted
  • Author
Posted

Check for codes.

 

Clean MAF and throttle body

 

Fuel filter

Fuel pump pressure

 

 

Great ideas, I will be doing this today. I will post back with what I find.

 

 

.

FrankenChevy Enthusiast

FrankenChevy

Posted
  • Author
Posted

No codes.

 

MAF

 

012_zpsdde7d353.jpg

 

015_zpsc86bbc07.jpg

 

Key on engine off fuel pump running. About 55psi

 

.

016_zps5a18d063.jpg

 

Key on engine off fuel pump off. About 52 psi

 

.

017_zpse8548922.jpg

 

Engine running. About 48psi

 

018_zps7b28f22d.jpg

 

Sorry about the focus, stupid camera.

 

Not sure how to clean the MAF, it looks kinda sensitive, I did clean the throttle intake.

 

Now I am thinking the pressure is a little low. I was thinking about a new regulator.

 

 

Thanks

 

 

txab Senior Enthusiast

txab

Posted
Posted

Use MAF approved cleaner.

 

Fuel pressure is low. Check pressure reg. for presence of fuel at vacuum line. Replace if fuel is found

FrankenChevy Enthusiast

FrankenChevy

Posted
  • Author
Posted

 

Use MAF approved cleaner.

 

Fuel pressure is low. Check pressure reg. for presence of fuel at vacuum line. Replace if fuel is found

 

 

 

Thanks Guys, I will do this and get back to you.

 

Great qoute in your sig, how true it is.

  • 3 weeks later...
FrankenChevy Enthusiast

FrankenChevy

Posted
  • Author
Posted

Just wanted to do a follow up on this.

 

The air filter was due so I put a new one in. Then cleaned the MAF, and installed a new fuel pressure regulator.

 

012_zpsd06ede86.jpg

 

015_zps0eddc2aa.jpg

 

Well the truck idles much better now, it's not perfectly smooth but does not shake the whole truck like before.

I think what helped the most was cleaning the MAF. I replaced the fuel pres. regulator and checked the pressure and it was not much different then before. I also bought a new fuel filter but have not put it in.

 

 

Thanks to everyone for your help. :cheers:

 

 

.

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