So when I first got my 2003 TB LS, I never noticed the temperature gauge was staying around the 180 range when warmed and wouldn’t go to the 210 range. Took a trip to Phoenix and then I noticed that the TB hit 210. With the help of the forum, seemed the Thermostat was the issue and with that I started buying parts.
I added the following since I was having a stall issue on my TB and since I was going to be working on the vehicle I might as well replace it and see if it cures my stalling.
https://www.youtube.com/watch?v=qk2__HwMIqY
Now for the tips I recommend that are not on the video since I made some mistakes that took me 2 days instead of 1 day to repair my Trailblazer.
Make sure you get Ac Delco parts only, while I have an issue that the parts are not made in America, they still have to pass standards by GM and I am not about to do this again! Also flush your radiator system, do a search as there are many methods to do the flush.
- ACDelco GM Original Equipment Thermostat 15-11006
- ACDelco 20382S Professional Upper Molded Coolant Hose
- ACDelco 26398X Professional Lower Molded Coolant Hose
- ACDelco 213-963 GM Original Equipment Engine Coolant Temperature Sensor
- Dexcool Radiator fluid, I didn't go Ac Delco this route and ended up getting Preston Dexcool.
- Crimps for the hoses if yours are bad, I ended up using all my old ones, as they seemed to be fine and still held a tight grip on the hoses.
I added the following since I was having a stall issue on my TB and since I was going to be working on the vehicle I might as well replace it and see if it cures my stalling.
- ACDelco 214-641 GM Original Equipment Vapor Canister Purge Valve (Drivers side on engine)
https://www.youtube.com/watch?v=qk2__HwMIqY
Now for the tips I recommend that are not on the video since I made some mistakes that took me 2 days instead of 1 day to repair my Trailblazer.
Make sure you get Ac Delco parts only, while I have an issue that the parts are not made in America, they still have to pass standards by GM and I am not about to do this again! Also flush your radiator system, do a search as there are many methods to do the flush.
- Make sure you have a 18MM deep cutaway socket for the Temp Sensor, trust me on this one, I didn’t have one and it took an extra day for me to install the Temp Sensor.
- The 18MM deep cutaway socket is very expensive that may seldom get used, so it’s hard to justify $40+ for that socket , as MRRSM recommended to me http://www.harborfreight.com/4-12-in-43-amp-angle-grinder-69645.html
http://www.harborfreight.com/4-in-40-grit-metal-cut-off-wheel-with-38-in-arbor-10-pc-61525.html and a $2 18mm deep socket for around $25+ is justified, since you can do some custom sockets with the cutaway feature in the future or do some metal work to grind off some the rust that the Trailblazers tend to have. - Be prepared to curse like a MFer, while I feel the Trailblazer has been easy to do some updates interior wise and outside motor work, this was a challenge, it’s not impossible but its time consuming and is awkward due to the tight spaces you have to work with and the fan and plastic bits just eating up your arms and bruising you.
- The alternator can be tricky, especially the bottom bolt since its in front of a AC hose, that just seems to say hey, how the hell you going to get that bolt out? I ended up taking off the plastic tray that holds the battery since I was just having an issue with the bottom bolt on re-install, after I took it off it made re-installing easy. I would recommend this to remove it for easier removal and re-install. The bolts near the horns can be tricky to get at, but its worth the room this gives you for that bottom bolt.
- I would pre-assemble the new Thermostat to the new lower radiator hose, this will make it easier to crimp in place, so you wont have fumble through all the hoses and cables from the top. If you need help on how it should go, just line it up with the old T-Stat and hose, and you should be fine. I ended up using the cover that was on the old radiator house since it was in good condition, it was tricky to get on since it seemed to tighten when I stretched it out and realized if you compress this cover it will widen and make install on the new hose a lot easier.
- Try to be positive while doing this, I let the heat and my annoyance get to me, that I didn't want to deal with the Temp Sensor anymore, lucky for me the board was giving me tips and advice that helped me fix my Trailblazer quickly, instead of waiting for another day.
- As I learned the hoses and Thermostat where original as when the Trailblazer left the showroom of Chevy. The upper hose was hard to get off and I had to cut it off, if you have to do this DO NOT let any debris fall into the pipe that goes down into the block. 10/30/02 date on the thermostat.
- Before putting back the Alternator now is the time to make sure all bots and nuts are tight, otherwise more scrapes to the arms to tighten any loose parts if you have to take the Alternator off again.
- Well the Trailblazer got up to 210 quickly, so everything seems to be working.
- Drive around and let the Trailblazer warm up and check for any leaks when you turn it off.
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