- Sep 3, 2014
- 14
I need some help. I have been through several forums and have not yet had a solution. I have a 2005 Chevy Trailblazer with 76,000 miles on it. Ever since I bought it 3 years ago I knew something was wrong. We bought this one to replace the 05 trailblazer that was totaled. It saved my wife and kids lives and never spent a day in the shop with 98,000 on it so we figured it would be great to get another one. Well long story short we first took it in last year for plug 4 misfiring on idle. They diagnosed it and told me the head needed to be replaced. So lucky for me we had an extended warranty and so we got that done. Our engine power and MPG's dropped significantly after the head was replaced. I took it back in several times and they stated nothing is wrong with it and it works just fine.
I finally ended up taking it to another GMC dealership and they saw problems with it right away. With their troubleshooting they determined the engine needed to be swapped because the leakdown test failed on all 6 cylinders. So the warranty company bought one with 20,000 miles on it. I thought all would be well at this point. However driving away I felt the same issues and saw the MPG's at the same 10 to 11 MPG in the city.
I mentioned the catalytic converter to the dealership and they said there was no code for it so it couldn't be the problem. So I bought an OEM cat anyways from the dealership and installed it, and took it to a muffler shop to have them replace the muffler. Still the same problems. It has a horrible time getting up the smallest of hills and just bad gas mileage. So I took it to an independent mechanic and as they test drove it they told me the engine load(according to their computer) was at 100 percent on the highway going 65 on a flat surface. That didn't seem right to them or me. So at this point I decided to come to the experts on these forums and see what you all might think it could be. Below is a list of everything I have replaced or had done to it. Thanks in advance for your advice.
1. Head Replaced
2. Engine Swapped with used one with 20,000 miles on it
3. OEM Catalytic Converter with Aftermarket muffler
4. Downstream(post cat) O2 sensor
5. Upstream O2 sensor
6. Camshaft Position Sensor(Distributor)
7. Cleaned throttle body with throttle body specific cleaner
8. K and N air filter
9. New AC Delco Plugs installed at dealer after engine swap
10. New Fan Clutch
11. New Water Pump
12. 4x4 module(4x4 was broke and there were a couple parts they replaced)
13. New Fuel gauge sender unit(in tank I believe its the filter and pump as well)
I finally ended up taking it to another GMC dealership and they saw problems with it right away. With their troubleshooting they determined the engine needed to be swapped because the leakdown test failed on all 6 cylinders. So the warranty company bought one with 20,000 miles on it. I thought all would be well at this point. However driving away I felt the same issues and saw the MPG's at the same 10 to 11 MPG in the city.
I mentioned the catalytic converter to the dealership and they said there was no code for it so it couldn't be the problem. So I bought an OEM cat anyways from the dealership and installed it, and took it to a muffler shop to have them replace the muffler. Still the same problems. It has a horrible time getting up the smallest of hills and just bad gas mileage. So I took it to an independent mechanic and as they test drove it they told me the engine load(according to their computer) was at 100 percent on the highway going 65 on a flat surface. That didn't seem right to them or me. So at this point I decided to come to the experts on these forums and see what you all might think it could be. Below is a list of everything I have replaced or had done to it. Thanks in advance for your advice.
1. Head Replaced
2. Engine Swapped with used one with 20,000 miles on it
3. OEM Catalytic Converter with Aftermarket muffler
4. Downstream(post cat) O2 sensor
5. Upstream O2 sensor
6. Camshaft Position Sensor(Distributor)
7. Cleaned throttle body with throttle body specific cleaner
8. K and N air filter
9. New AC Delco Plugs installed at dealer after engine swap
10. New Fan Clutch
11. New Water Pump
12. 4x4 module(4x4 was broke and there were a couple parts they replaced)
13. New Fuel gauge sender unit(in tank I believe its the filter and pump as well)