Again, Good Luck!
03 Trailblazer 4.2 Sluggish Acceleration
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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So I tried to get my dad to help me do that test and he just said no and took me to go buy a new sensor so... yeah... guess we'll see how that goes lol
K so swapped that out and took it for a test drive... seemed to do better until I tried to take it onto the highway to test its climbing to see if it was any different ant it wasnt... It still bogs hard on shallow inclines and the transmission is still s hifting hard (after 3k+ RPMs)
No need to use a pressure Guage just remove the upstream o2 sensor and then drive to see if the power is better. Will be loud but won't hurt anythingHello! 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!!!
Ill try this once I can get my hands on an O2 sensor socket...No need to use a pressure Guage just remove the upstream o2 sensor and then drive to see if the power is better. Will be loud but won't hurt anything
CAT, CAT, CAT! Just went through this. and tested many things & replaced many things etc. You can find a back pressure Guage to put into the upstream O2, and then the downstream O2 sensors and when it shows higher than 1 or 2 on the upstream it's the catalytic converter. Slow on hills and grades, shifting issues, sputtering soon after taking off. When the Cat fouls, clogs and degrades the air has no place to go CPU doesn't know what to tell the throttle body and all the isensors go haywire trying to read and balance. Sometimes money can be an issue and you need that money for the Cat.. converter. You can even unplug the 1st upstream O2 sensor and go for a brief drive if there is any small sign of better running motor it's the converter. Many people, even shops, will tell you Cats never go bad, " save your money". Well, when you replace it you will not believe the difference and how good your 4.2 can run; and, if tha that isn't the problem you are having and describing I'll move you myself. BTW I got my Walker universal Cat from Amazon for $99. It was a previously damaged package but the item was perfect. Hope you get lucky with yours roo!
Mine was a Cat, same conditions but sounds like you have some lights to take care of. My 2003 has needed coils, plugs and on another occasion a loose intake manifold causing a rough idle. 255,000 miles so far..good luck!
I am no fan of Ravalli's "make a joke of everything" attitude, to the point I hate reading his responses. But I do because once you get past his attempts at humor when most need advice, not jokes, his advice is 99.9% spot on.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...
Superchrged111 is the ONLY person on these forums who advocates a full trans. flush. The ONLY one.
Take that as you will.
I am on other forums where I'm not the only one advocating for full flushes on 4L60Es, there's nothing special about the ones they put into Trailblazers. Have fun being a hack if you think it's cool to keep 20 year old fluid in your transmission. Does that logic work for the engine? Brakes? Cooling system? Power steering system? Axles? Transfer case? Or does old, nasty fluid cause issues there too? Or do you just ignore it?I am no fan of Ravalli's "make a joke of everything" attitude, to the point I hate reading his responses. But I do because once you get past his attempts at humor when most need advice, not jokes, his advice is 99.9% spot on.
Superchrged111 is the ONLY person on these forums who advocates a full trans. flush. The ONLY one.
Take that as you will.
GreaseGirl95, what DTCs are now present? Did the P0014 and P1345 go away or are they still present?
In my earlier response I suggested you unplug the O2 sensor. I meant to type that you remove the upstream O2 sensor and then go for a test drive as others have suggested.
Thanks and Good Luck!
In my earlier response I suggested you unplug the O2 sensor. I meant to type that you remove the upstream O2 sensor and then go for a test drive as others have suggested.
Thanks and Good Luck!
I havent been able to remove and test drive with upstream O2 out but I also havent driven enough for the codes to repopulate for anything yet. I have to drive to and from work tomorrow so hopefully that will be enough finally to make it populate an error report for meGreaseGirl95, what DTCs are now present? Did the P0014 and P1345 go away or are they still present?
In my earlier response I suggested you unplug the O2 sensor. I meant to type that you remove the upstream O2 sensor and then go for a test drive as others have suggested.
Thanks and Good Luck!
OK. Thanks for the update. If I remember correctly, O'Reilly, AutoZone & Advance have a specialty loaner tool program that includes an O2 sensor socket.
Good Luck!
Good Luck!
O2 sockets suck! Last stubborn one I pulled I ended up cranking a set of these bad boys down on and whacking with a hammer after a couple of torch cycles to break it free. . . and I don't live in the rust belt!
![Wrench Bicycle part Bone Font Musical instrument accessory]()
You snap them down, then cram a screwdriver back in the red screw and keep tightening them. They are le-git and THE reason I got that O2 out as opposed to saying to Hell with it and welding in a new bung with a new sensor elsewhere. YMMV.
You snap them down, then cram a screwdriver back in the red screw and keep tightening them. They are le-git and THE reason I got that O2 out as opposed to saying to Hell with it and welding in a new bung with a new sensor elsewhere. YMMV.
I have some of those clamps however mine doesnt have a spot in the back to tighten it down more, just the nob... I'll figure it out I guess hahah
Just get an O2 socket, then right before you want to remove the O2 sensor, run the engine for a couple of minutes to let the exhaust manifold to heat up and the fitting where the O2 sensor screws into should expand ever so slightly, It will require some effort to break free so if you have a breaker bar or a gorilla to assist you...
If at first you don't succeed, run the engine for another couple of minutes then try again. Using a penetrant like Kroil, PB Blaster,Liquid Wrench will not work because of the gasket on the O2 sensor. Just keep your fingers crossed that who ever installed the O2 sensor used a decent amount of anti-seize compound. Also, you might want to get a hose clamp to put around the O2 sensor socket down by the hexagonal portion of the sensor in order to provide a bit more clamping force from the socket to the O2 sensor.
Good Luck!
If at first you don't succeed, run the engine for another couple of minutes then try again. Using a penetrant like Kroil, PB Blaster,Liquid Wrench will not work because of the gasket on the O2 sensor. Just keep your fingers crossed that who ever installed the O2 sensor used a decent amount of anti-seize compound. Also, you might want to get a hose clamp to put around the O2 sensor socket down by the hexagonal portion of the sensor in order to provide a bit more clamping force from the socket to the O2 sensor.
Good Luck!
Dumb question... is a trailblazer a 2WD or a 4WD?
It can be either. Easier way to tell is to look at the front dash to the right of the steering wheel.and immediately to the left of the radio. If there is a knob there and it is labeled with 4-Hi 4-Lo 2 WD, then it is a 4 wheel drive. NOTE, if you have a rear windshield wiper, the 4 WD know will be right above the Rear Windshield Wiper and Washer Control Knob.
Logic also includes real world experience. I used to be like you. Ignoring other people's practical experience just to fit my own narrative. I lost a lot of races because of that. Sometimes, right just doesn't make sense, but it doesn't make it less right.I am on other forums where I'm not the only one advocating for full flushes on 4L60Es, there's nothing special about the ones they put into Trailblazers. Have fun being a hack if you think it's cool to keep 20 year old fluid in your transmission. Does that logic work for the engine? Brakes? Cooling system? Power steering system? Axles? Transfer case? Or does old, nasty fluid cause issues there too? Or do you just ignore it?
Please stop arguing over the flush guys, its not helpful here 
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