Car won't accelerate over 55 mph - 2006 Chevrolet Silverado 1500 2WD

Take extra caution while performing dirve cycles on public roadways. Drive cycles can be difficult to follow under normal driving conditions. Begin by: - Start the engine. Idle the engine in drive for two and a half minutes with the A/C and rear defroster on. - Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle. - Hold at a steady speed of 55 mph for three minutes. - Decelerate (coast down) to 20 mph without braking or depressing the clutch. - Accelerate back to 55 to 60 mph at ¾ throttle. - Hold at a steady speed of 55 to 60 mph for five minutes. - Decelerate (coast down) to a stop without braking. If all other emissions systems are functioning properly, completing the drive cycle above will set the "readiness flags" required to pass the smog check. It will not hurt to perform the drive cycle 2 or 3 times before the smog test.

Car bogs down when I accelerate !!! - Car Forums and Automotive ...

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I have a 1994 Cavalier 4cyl and it bogs down and struggles when I come from a dead and try to accelerate and sometimes when I get upto 55-60 mph it does it ...

1. The testing has to start with the vehicle under 122 degrees F. Start the engine and idle for 2.5 minutes in Drive (auto) Neutral (MAN) A/C and rear defogger ON.

2. A/C OFF, accelerate to 55 MPH at 1/2 throttle and then 3 minutes of steady state cruise at 55 MPH.

3. Clutch engaged (MAN) no braking decelerate to 20 MPH.

4. Accelerate to 55-60 MPH at 3/4 throttle and 5 minutes of steady state cruise at 55-60 MPH.

5. Decelerate, no braking to end the drive cycle.

In some cases the Powertrain Control Module (PCM) will go into a logic lock not letting the readiness monitors run. Removing the battery cables and touching the two together will normally take care of the logic lock condition.

The solenoid engages the lockup part of the torque converter.
So it could be either one.
The solenoid would need to be tested.

It might be a blown head gasket!

Check your catalytic converter under car...When it starts to clog up...Your car want accelerate correctly...Puts back pressure on your motorr

I have to ask

Why are you even driving a car that has
whatever that problem is & doing so for
weeks or longer?

Surely you know that you have somewhat serious
issues, when a car won't go over 55 & gets worse!

What does catching mean?
Now it won't start or catch or go
over 55

When are you going to a repair shop?
Before you ruin something or have a costly repair?

Probably you have a problem with one of the Vale Body valves , you need to check it with a diagnose system

How about the CV joint?? were they inspected for wear??