99 Sierra Starting Problems

[estein00]

Hi,

 

I have a 99 sierra 2wd 5.3 and if the truck sits for an hour or so whenever I go to start it, it sometimes cranks for about three seconds, starts, and then idles rough if you dont give it some gas. If i shut it off and then start it again it fires right up, what is going on?

 

Thank you.

[ColoradoSkiCountry]

Time for a new fuel sending unit in the gas tank (Fuel Pump) and you should probably check/replace your fuel pressure regulator as well. Both the pumps and FPR are VERY notorious for failing easily on the GMT-800s. Do a search for hard starting or fuel pressure regulator or fuel pump issues, and you'll find posts going back 6 or 7 years on here when everyone was driving the GMT-800s and had the same issues.

 

Hi,

 

I have a 99 sierra 2wd 5.3 and if the truck sits for an hour or so whenever I go to start it, it sometimes cranks for about three seconds, starts, and then idles rough if you dont give it some gas. If i shut it off and then start it again it fires right up, what is going on?

 

Thank you.

[K1500Tech]

Sounds like the fuel pump is bleeding off while its sits.

[estein00]

Sounds like the fuel pump is bleeding off while its sits.

 

Thank you guys

[98 Z71 SLT]

Disagree

 

Fuel pressure regulator is leaking

 

Leave the fuel pump alone...nothing wrong with it

[jblakeney]

Is the pump loud??? It sounds as the fuel pump has death danced..

 

Jbo

[Mustard2000Tahoe]

Hey, I had the same problem about a month ago. A tuneup, fuel filter, new fuel meter assembly and $1000 later and it still wasnt fixed. They said the fuel pump was a little weak but okay. It finally died on me when I was driving and then I found that the positive terminal bolt on my optima red top was stripped out from being overtightened. $4 battery bolt and she starts like a champ! Lesson learned, never overlook the small shit!

[estein00]

Disagree

 

Fuel pressure regulator is leaking

 

Leave the fuel pump alone...nothing wrong with it

 

How can i fix that?

[txab]

Buy a new one and install it. It's in the middle of the fuel rail, on the intake manifold, on the driver's side, held in by a clip, with a vacuum line attached to the top of it.

 

 

Picture of a FPR in this post.

[Gone Again]

Hi,

 

I have a 99 sierra 2wd 5.3 and if the truck sits for an hour or so whenever I go to start it, it sometimes cranks for about three seconds, starts, and then idles rough if you dont give it some gas. If i shut it off and then start it again it fires right up, what is going on?

 

Thank you.

 

Pull the vac line off the FPR and check for raw gas. Take an air hose and blow gently ACROSS the vac port on the FPR. If any fuel is present the FPR is bad.

[estein00]

Hi,

 

I have a 99 sierra 2wd 5.3 and if the truck sits for an hour or so whenever I go to start it, it sometimes cranks for about three seconds, starts, and then idles rough if you dont give it some gas. If i shut it off and then start it again it fires right up, what is going on?

 

Thank you.

 

Pull the vac line off the FPR and check for raw gas. Take an air hose and blow gently ACROSS the vac port on the FPR. If any fuel is present the FPR is bad.

 

 

I pulled the vac line off and there was no fuel pouring out but it looked a little moist. Also when i had the vac line off of the FPR a little gas kept on coming out of the top of the FPR. Does this mean its bad? Also about 30 minutes after i had drove it i tested it does that change anything?

 

Thank you.

[Gone Again]

Hi,

 

I have a 99 sierra 2wd 5.3 and if the truck sits for an hour or so whenever I go to start it, it sometimes cranks for about three seconds, starts, and then idles rough if you dont give it some gas. If i shut it off and then start it again it fires right up, what is going on?

 

Thank you.

 

Pull the vac line off the FPR and check for raw gas. Take an air hose and blow gently ACROSS the vac port on the FPR. If any fuel is present the FPR is bad.

 

 

I pulled the vac line off and there was no fuel pouring out but it looked a little moist. Also when i had the vac line off of the FPR a little gas kept on coming out of the top of the FPR. Does this mean its bad? Also about 30 minutes after i had drove it i tested it does that change anything?

 

Thank you.

 

 

FPR is BAD!

[nowicksl]

Finally a search worked wonders for me! Thanks for this board and good information. Pulled the plug from the Press Regulator and fuel came out - had a terrible problem with HOT STARTING and rich fuel smell when it finally kicked in. Fix is in!