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03 Trailblazer 4.2 Sluggish Acceleration

5586 Views 106 Replies 15 Participants Last post by  Trailnut
Hello! New here... Just got an 03 Trailblazer 4.2 with 212k miles on it with some sluggish acceleration. I need to replace the VVT solenoid (have it being delivered tomorrow) but I am not sure if that will still fix the issue. If I do replace the solenoid and its still sluggish, what are other issues that can cause this issue? Ive seen reports of like a clogged Cat Conv but I think it may be transmission related (such as the torque converter) because it has a hard time with hills and then also it has an issue changing gears... Any suggestions would be appreciated!!!
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Pressure test for a plugged cat first --- it's cheap and a slam-dunk easy test at almost any muffler shop.
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When you say cheap, how much are we talking? Im working with my hubbys money rn while he's over seas so I need to know how much to ask him for the money
Realistically .... $30 - $40 for the pressure test including the screw fitting.

Gauges won't even be necessary if it's bad enough to affect driveability.

Got a power drill?
Do the test yourself.
The fitting is cheap after the test to plug the hole up.
Don't flush the transmission ... service it correctly by dropping the pan and then you can see inside to get a decent appraisal of it.

Tear the old filter apart to see what it's caught and clean the magnet to see how much ferrous material it caught too.

Those things won't be done by flushing. You dont need to replace all the fluid every time ... besides, I would never allow my customers to risk crippling their vehicle by flushing.

I've had overhauls created by other shops that did flushing. It's just risky on an older unit.

PS ... the reason why I recommend the drill-and-screw pressure test is because not many people have the special socket to remove an oxygen sensor without damaging it.

PPS ... don't take any advice from AAMCO. That's like going to a witch doctor for orthopedic surgery. Belts, hoses and a wax job won't fix performance issues.
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The VVT alone will drop power and performance .... repair the obvious and then let the chips fall.

Don't go poking the bear!

VVTs fail from rusting into a locked position; be sure to ask about that when you can.
By all means ---- flush it!

That singular process bought me a 52 foot yacht in Dana Point.

Water Sky Boat Watercraft Naval architecture

Love it --- bad advice backed up by ONE anecdote.
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Yeah I already priced the ignition coil from Rock Auto... will order it tomorrow after work... Also Ravalli, Its kind of hard to trust the advise from someone who suggested to drill a hole in my muffler/cat converter...
I didn't say drill a hole in your cat. If you get the test kit, it has full instructions to drill a small hole in the pipe just ahead of the cat and read the pressure there after you install the special fitting.

THEN --- after the test, they provide a nice small screw to close it back up again.

MOST people own a drill ---- not too many people have the sensor socket nor know how to use it.

It was a suggestion to save you some money and even though you believe I told you to drill into the cat --- I did not.

BTW --- as a CARB/CalEPA Brake-Lamp-Emissions Inspector for over 50 years for the State of California and as an inspector-installer-adjuster and friend of the court --- that drill/screw kit is safe, legal and cheap.

I'm outta here --- listen to "people" with "lots of experience" and anecdotes ..... just do what you want......
Good grief!

If it hung around NJ too long, it may be an empty box by now.

Motor vehicle Window Pollution Mode of transport Wood
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Do you mean to tell that there was excess fuel in the exhaust system and that's your problem?

Bat guano!

Where do these ideas come from?
.............I have left the building .......

Wheel White Black Rim Automotive tire
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