Chevy Trailblazer Shakes And Stalls- GMC Envoy Thermostat Replacement

Question:
I have a 2004 Chevrolet Trailblazer. Why is it shaking and it turned off? I had the air conditioning on an when i got off the freeway and stopped at a light thats when it starts shaking and also turned off please help.

Answer:
Your truck stalling when coming up to a stop is a very common problem of carbon in the throttle body. You need to clean the throttle. Carbon buildup prevents the electronic throttle from being able to control the idle, especially with the A/C on, or turning at slow speeds. After cleaning, let the truck, start it up, rev it a few times to clear the cleaner out, then let it idle for 5 minutes, turn it off for 1 minute, then let idle for 5 minutes. Shut it off again, then take it on the expressway. When you get off, come to a stop and let it idle in gear for another minute. This should reset the idle. If not, a scan tool hooked up tot he computer will be needed to relearn the idle.

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Question:
1996 Chevy Blazer Vortec 4.3L V6 engine. While driving on the highway my blazers engine just shut off. I pull over, wait a minute, then start the engine and continue down the highway again. A minute later the engine shuts off again. This happens 7 or 8 times. Everything is fine for a week then it did it again. Why is the engine shutting off? No warning lights come on and all the gauges are normal. I got the garage to look at it and they said no codes were coming up. So the blazer starts fine and runs fine just shuts off whenever it feels like without warning.

Answer:
This may be a problem of a failing fuel pump in your truck. This is pretty common on this truck. Normally this would cause the truck to sort of stumble before it stalls. If it just instantly shuts off like you are turning the key off, then it may be a problem in the ignition switch in the steering column, or an ignition control module.

It may be hard to find, especially if it starts right back up. You would need to have a fuel pressure gauge on the engine and watch to see if it drops as it stalls, and if it is low when trying to restart- and it won't. Fuel Pressure needs to be at least 55 PSI. You can also try tapping on the ignition switch to see if you can cause it to stall. The lower steering column cover would need to come off to the access the switch.

Question:
GMC Envoy 4.2 L 6cyl. We did a replace GMC thermostat but the lower hose is warm but not hot. The upper hose is hot what dose that mean?

Answer:
Make sure that you bled the air out of the cooling system. It can take quite some time. After it warms up with cap off, take for a drive and do a few hard acceleration. You should hear air / coolant sloshing throught the dash heater core. Then shut it off and let it cool down. This will usually bleed the air.

Question: My 2008 Chevy Trailblazer will not start. I believe it is a computer problem. It just turns over. I wait ten minutes and I get lucky and it will start. It has gotten worse the last couple of days and now it will not start at all. Just turns and no go.
 Answer: OK. Well, you would need to find out if there is adequate fuel pressure first. If so, then the next step is to see if there is spark to the spark plugs.

I took gas down the throttle body with a spray bottle. So it was primed still no start.
 OK, then my guess is that there is no spark. If there were, it should have tried to start at least after pouring gas in. That could be a faulty crank potion sensor or yes, the computer.


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