Need help with troubled '06 Trailblazer

[TroubledChevyTB]

We have had an ongoing problem for the past 3 months with our '06 Trailblazer. Until this problem, it has been a great vehicle. It started with sputtering and engine cutting out while driving. One mechanic diagnosed the problem as the throttle body, but was unable to order one at the time so we took it to our local Chevrolet dealer. Dealership mechanic said it wasn't the throttle body but the catalytic converter. We had the catalytic converter replace, but that didn't help. A week later the problem was worse. It went into reduced power mode several times. We took it to another Chevrolet dealer and they replaced purge solenoid valve and vent valve. Still not working properly so we took it back to the dealership and they replaced the 02 sensor. Still not working properly so we took it back again at they replaced MAF and MAP sensors, performed top engine soak and still could not fix the problem. We drove it home, but still can't drive it on a regular basis. At the advise of GM specialist, they wanted to pull the intake and check for water in the injectors. That would be another $400 for this exploratory work -- no guarantee it would work -- just a guess. We have spent over $1200 at the dealership and TB still doesn't work. Any ideas/answers would be appreciated so much! We feel the car is still in good shape -- just has a problem that can't be pin pointed.

[petevw]

Were there any diagnostic codes stored in the computer that the dealer read?

It almost sounds like a bad coil pack. If one goes really bad, it will make that cylinder cut out, shake, and probably give a blinking SES light and/or reduced power light.

Was the vehicle in any big rain storms just prior to the problem starting?

Getting back to the throttle body, did the dealer remove and try CLEANING the throttle body? This is something most backyard mechanics can do. It also involves disconnecting the battery for about 45 minutes while doing the cleaning to re-set the computer to factory settings.

[TroubledChevyTB]

We actually changed the spark plugs during all this also. The 1st cylinder had been wet at one time because the rubber neck of the coil was rust colored. This did not seem to be a concern to the dealership.

We were told they had cleaned the throttle body. We do not have a print out of all the codes that were reported.

Changing the coil is certainly an option for us to try. Would a bad coil not show up in the codes in the computer? Seems the dealership would have known to check this.

Thank you for any more thoughts you have about our Trailblazer. We really like the car and hate to give up on it. It has 124K miles, but we feel it has many more to give!

Thanks, Troubled Chevy TB

[TroubledChevyTB]

Today at AutoZone, the following codes were showing on our Trailblazer:
P0101 and P0068.

Thanks again for any help you can give us.