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Posted

I have a 2010 Silverado 5.3 vortec and my it won’t rev past 4000 rpm even in manual mode 

I had an exhaust leak that we thought caused it originally and we fixed it . The problem went away for a bit but now the rpm trouble is back again any help is appreciated .

could it Be bad spark plugs and wires or something else? Fuel filter?

Posted

I've been told there is no user-serviceable fuel filter on those trucks.  The filter is a strainer-sleeve type inside the fuel tank with the fuel pump and fuel gage float.  

Posted

If you had an exhaust leak, you might of burnt your cats( thinks that its running too lean, adds fuel and burns cats). How long was it running with  an exhaust leak?

If the cats are burnt, its will clog up the exhaust and the flow will be restricted. 

Posted

I had that problem once. A 94 Z-28 that used a qt of oil every 2500 miles. At 80K miles it loss some power and revving. Removal of the cats fix the problem.


Sent from my iPhone using Tapatalk

Posted (edited)

Any codes?

Mileage?

Has it  ever had any maintenance?

What's missing fuel or spark?

Compression test?

Is it a beater?

Edited by It's Tim
Posted
38 minutes ago, BlancoSilverado said:

If you had an exhaust leak, you might of burnt your cats( thinks that its running too lean, adds fuel and burns cats). How long was it running with  an exhaust leak?

If the cats are burnt, its will clog up the exhaust and the flow will be restricted. 

I had the leak for quite a few months only because I had no time to fix it .

would that be the reason the truck won’t go past 4000 and stop the vehicle from speeding up ?

it just seems like a big result of a semi small problem 

I’m thinking about doing a tune up as well to make sure all my plugs are good anyway .

Posted
1 minute ago, It's Tim said:

What's missing fuel or spark?

Compression test?

Is it a beater?

Nothing is missing it runs great until I floor it then it gets stuck at 4000 and doesn’t shift along with not speeding up and no it’s not a beater it was well taken care of

Posted
2 minutes ago, Dawson58 said:

I had the leak for quite a few months only because I had no time to fix it .

would that be the reason the truck won’t go past 4000 and stop the vehicle from speeding up ?

it just seems like a big result of a semi small problem 

I’m thinking about doing a tune up as well to make sure all my plugs are good anyway .

Forgot to mention I do have an air intake and headers on the truck would that also be a factor .

Posted (edited)
5 minutes ago, Dawson58 said:

I had the leak for quite a few months only because I had no time to fix it .

would that be the reason the truck won’t go past 4000 and stop the vehicle from speeding up ?

it just seems like a big result of a semi small problem 

I’m thinking about doing a tune up as well to make sure all my plugs are good anyway .

Because i haven't heard or seen the vehicle, 

is it hesitating to get up to 4k, or is it shooting up to 4k then "stalling" at the rpm? is it staying at 4k or is it going from XXXX-4k(3600 to 4000 back to 3600"cycling")?

you can pull pull the front O2 sensors and see if it will go higher, if it does then it is a cat problem. if not, might be a governor or a different problem. 

 

Are you reving it out? is it only when you are in drive. Are you in neutral and trying to go past 4k?

Edited by BlancoSilverado
Posted
8 minutes ago, BlancoSilverado said:

Because i haven't heard or seen the vehicle, 

is it hesitating to get up to 4k, or is it shooting up to 4k then "stalling" at the rpm? is it staying at 4k or is it going from XXXX-4k(3600 to 4000 back to 3600"cycling")?

you can pull pull the front O2 sensors and see if it will go higher, if it does then it is a cat problem. if not, might be a governor or a different problem. 

 

Are you reving it out? is it only when you are in drive. Are you in neutral and trying to go past 4k?

It shoots up then stalls at 4K  and yes it only happens in drive I know the factory governs the limiter at 4k In park and neutral but not when driving and it can get up to any speed when driving normally but the second I floor it that’s when the problem arises 

Posted
Just now, Dawson58 said:

It shoots up then stalls at 4K  and yes it only happens in drive I know the factory governs the limiter at 4k In park and neutral but not when driving and it can get up to any speed when driving normally but the second I floor it that’s when the problem arises 

No idea then, sorry. I would need to see/hear the vehicle.

Posted

If the engine can free rev past 4,000rpm when you pop it into neutral while moving, it's not going to be exhaust related.

 

Seems either calibration related or transmission related.

  • 11 months later...
Posted
On 1/13/2020 at 12:58 PM, Dawson58 said:

Nothing is missing it runs great until I floor it then it gets stuck at 4000 and doesn’t shift along with not speeding up and no it’s not a beater it was well taken care of

How u make out u ever figure this out  I just got a 2012 silverado 2500hd with 6.0l and its doing same thing as u are describing. U ever figure it anything out?

  • 1 year later...
Posted
On 12/19/2020 at 5:15 PM, Nsnyder3 said:

How u make out u ever figure this out  I just got a 2012 silverado 2500hd with 6.0l and its doing same thing as u are describing. U ever figure it anything out?

Hello i have a 2007 silverado 1500 its doing the same thing. i have replaced everything i can think of. Plugs, coils, wires, fuel pump, cats, mass airflow sensor. im stumped. i hope someone has figured somthing out. It will run normal in mannual 1st, the rest of the gears bog out around 4000rpm

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