I just bought a 99 z71 silverado. It runs great for about a half hour or so every day, but then once it gets warmed up good it starts to lose power. No missing or check engine or anything has ever came on. I push the accelerator down and it does nothing. It has never died on me or anything, just losses power. It will drive fine if you barely try to accelerate, but if you push the pedal down very far, nothing, wont pick up rpm's at all. It has the 5.3 and is 4x4 if this helps. Please help, it's the only vehicle I have to drive to work. Thanks.
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99 silverado losses power please help
- Thread starter nutznky
- Start date
have you checked the fuel filter and pump? if so and all is well there then check injectors and try some carb cleaner or octane booster. The new fuel w/ethanol is not good for these older engines and like to build up on engine parts and cuse a power loss. I have had a similar issue with my 97 silverado and these things have helped a lot.
99 silverado
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check fuel pressure when its acting up.
Generally, an overall lack in power like this is somewhat ominous.
First things first, do you have an accelerator cable or is your truck drive by wire? I beleive the LM7 still was accelerator cable..check to see if its working. Ive had two 96-99 3/4 tons with the vortecs get bad throttle cables that eventually snapped.
If your lack of power is fuel pressure, it is generally accompanied by an excessively lean condition which can cause backfire through the intake.
Is your transmission stuck in 3rd gear?
Other factors which will cause low/no power is no ignition advance, since you have COP ignition, this would be entirely computer if there was no CEL.
The most common cause of this condition mechanically is slipped timing chain or excessive blow by. Pull your PCV vent or valve and see if there are gasses being pushed like a freight train past the valve. If so, run a compression check.
Hope some of this points you in the right direction
First things first, do you have an accelerator cable or is your truck drive by wire? I beleive the LM7 still was accelerator cable..check to see if its working. Ive had two 96-99 3/4 tons with the vortecs get bad throttle cables that eventually snapped.
If your lack of power is fuel pressure, it is generally accompanied by an excessively lean condition which can cause backfire through the intake.
Is your transmission stuck in 3rd gear?
Other factors which will cause low/no power is no ignition advance, since you have COP ignition, this would be entirely computer if there was no CEL.
The most common cause of this condition mechanically is slipped timing chain or excessive blow by. Pull your PCV vent or valve and see if there are gasses being pushed like a freight train past the valve. If so, run a compression check.
Hope some of this points you in the right direction
ChevyBobby
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As the issue only arises when the vehicle is warm, I'd have to think it was a thermo issue, and likely the vehicle running in "limp" mode when the component heats up and raises an alarm electronically. What in your vehicle could do that? Anything not receiving the normal flow of cooling, whether that be air or liquid.
"Loses" is the proper way to spell the word you were taking stabs at in your title and OP. "Losses" is a word that refers to items lost in the past, generally money.
"Loses" is the proper way to spell the word you were taking stabs at in your title and OP. "Losses" is a word that refers to items lost in the past, generally money.