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Hello my automatic 2002 silverado 1500 5.3 wont go past 2000 rpm while in drive. I can hit the rev limiter in park tho. Also if I manually shift In to 2nd gear only it will be normal and go past 2000 rpm. Anyone know whats wrong?
 

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Hello my automatic 2002 silverado 1500 5.3 wont go past 2000 rpm while in drive. I can hit the rev limiter in park tho. Also if I manually shift In to 2nd gear only it will be normal and go past 2000 rpm. Anyone know whats wrong?
remove the O2 sensors upstream of the cat converter ... cats can be messed up melted down restricted..drive it with the O2 removed if drives good then converter.
another test is start engine cold . then crawl under truck . put each hand on the 2 converters if the converters do not get hot the same amount then the colder one is bad.
 

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Hold off on the O2 sensor removal!!! There is a much easier test to diagnose plugged cats before you get into any labor intensive work.

Warm up motor for about 10 minutes at idle.

There are 2 variant tests that can be done depending on what tools you have.
Test 1, the poor man test, rap the motor to 5 grand a few times. Does the motor get to 5 grand (or rev limiter) within 2 seconds from idle???
If yes, ...no plugged cats.
If no, or not sure sure, get a vacuum gauge attached to a full vacuum port (test method #2). Vacuum should be around 16 to 17 inches at idle. Raise engine speed very slowly to 4 grand without any engine load. Is the engine vacuum within 2 inches of original vacuum reading???
If yes, no plugged cats.
If no, the vacuum reading will be at 10 inches or lower for a plug cat / collapse exhaust pipe issue. Might even hear a "moaning" sound coming out of the throttle opening.

Next diagnostic procedure if plug cat test passes:

Get you rear axle on 2 stable jack stands.

Attempt to drive the truck in gear up to 70 m.p.h. indicated by the speedo. Count each of the shifts and what speed they occurs at.

Good chance your check engine light will go on for the front wheels not turning. No big deal.

Next test is to place the trans in the lowest gear, does it go over 2 grand easily??? Do it with each higher gear. Does any gear prevents the engine from going over 2 grand???

If you fell any vibration in the seat of your pant's, especially around 45 to 55 m.p.h., get the rear wheels spin balance. If you have unbalance rear wheels, you will have unbalance front wheels too.

Report back with your findings.
 

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Hello my automatic 2002 silverado 1500 5.3 wont go past 2000 rpm while in drive. I can hit the rev limiter in park tho. Also if I manually shift In to 2nd gear only it will be normal and go past 2000 rpm. Anyone know whats wrong?
so HOW DID YOU FIX IT !
 
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