Chevy Trailblazer Is Hard To Start

Question:
When i drive for awhile and then stop like shopping when i go to start it, it acts like its flooded and it takes a few time to get started and when it does it shutters for a bit then evens out. I've had it on the engine test thing and they told me that it was the serpentine belt and thermostat which i dont think that has anything to do with how it acts. 2003 Chevrolet Trailblazer LS. Warning lights: service engine soon sometimes.

Answer:
Your check engine light can come on if you have a bad thermostat, and that also causes Driveability issues. When the engine computer can't tell what temperature the vehicle is running at, it defaults in a set fuel/air ratio to prevent damage from overheating. This can seem like it's running poorly and would cause a hard starting condition.

Assuming you don't have any other trouble codes, you should at least get the thermostat replaced and a new belt if they said it was bad. Otherwise, from what you describe, you could have a clogged air filter, carbon build up in the throttle body, clogged fuel filter or injectors that could be causing your hard start and rough running. Best to get checked out fully by a trained technician.


Question:
Repairs as stated above have been done, now the vehicle will not go into any gear. Act like all gears are neutral. Replaced battery, sat for a week and battery was graveyard dead. Any ideas? All dash lights are on and gauges are all to bottom or left....none work. 2004 Trailblazer ext. All lights are on. Cleaned throttle and replaced battery.

Answer:
With the gauges bottomed out and the other problem you are having, it sounds like either a module may have been damaged if you tried to jump start it at any time. This can cause a voltage spike and take out a module. But these different problems cannot be related to one module. You may have damaged several.

If you did not ever jump start the truck, then it may be a faulty ignition switch. This is what feeds power to most of the trucks electrical systems. That would explain the gauges being all the way down- low voltage. It could also explain the transmission problem. Low voltage to the trans shit solenoids.

Try this: Cycle the ignition from off to on very quickly many times. Sort of- turn,turn back, turn,then back. Do thus fast and harshly. This will sometimes cause a faulty ignition switch to correct it self for a little while, or to at least fix a few of the problems.


Question:
2005 Chevy Trailblazer. Battery got replaced. Question: just replaced battery now when I turn on the a/c the car shuts off. Even on park, or while driving.

Answer:
This is a common problem of carbon buildup in the throttle. When you replaced the battery, the computer is trying to set / learn the proper idle position. if there is a lot of carbon in it, the computer cannot compensate for it.

Give the throttle a good cleaning, take it out on the highway and blow it out real good, then let the truck idle for a few minutes. Shut off the truck and let it idle for 2 more minutes, then shut it off for 5 minutes.

Now restart and see if the problem clears up. If the engine light is on, you will need to have it scanned for codes and maybe cleared to finish this procedure.


Question:
2008 Chevrolet Trailblazer. I went to run some errands at which time had had no problem with engine starting and turning over. The next day I went ro start the car and it would not start not cranking over at all I have all of my elecgrical components working, my battery is putting out around 12.3.

I checked battery next day there was no drainage and of course it still won't crank over when I do try to start it the engine light comes on with battery light but no other lights and gauge dose t move a couple times got a light resembling a pad lock doors lo k and unlock with remote pad oils good checked all fuses all look good. Problem occured overnight.

Answer:
A battery can still be bad even though it shows 12.3 volts. You need to check voltage when cranking but your truck does not crank. You can possibly have a bad starter. You can try tapping on it while someone holds the key in the crank position to see if it frees up. You could also have a bad starter relay. In the underhood fuse box there is a relay that controls the starter. You can swap that out with another relay to test it.

The other thing is the theft light that's on the dash. That's what the lock and key image means. You may have a security issue not allowing it to crank. This can be caused by several things. If you have a non-factory aftermarket auto start system you first need to disconnect that from the truck because those are known to have problems. If you don't have such a system then the sensor inside the steering column is most likely the problem and would need to be replaced. Then a theft relearned procedure would need to be performed.


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