Jerky start-up and a lot of smoke?

HISHAM200974

MEMBER
2008 CHEVROLET TRAILBLAZER
6 CYL
4WD
AUTOMATIC
194,000 MILES

Jerky start-up and a lot of smoke comes out from the exhaust for 5 minutes. Plus, a temperature meter up and down and RPMs up when the temperature meter is reading 0. Note, that I have some code like p0411 and note that last year I changed the temperature sensor and thermostat.

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1 Reply

KEN L

MASTER CERTIFIED MECHANIC
48,329 POSTS

So, the p0411 code is for the air injector system for incorrect flow. This is to aid the emissions system so I don't think this will make the engine run poorly at start up. I have seen a sticking fuel injector load a cylinder up with fuel after the engine is shut off. I would remove the spark plugs and look for one that is different than the rest (black/soot) is the cylinder have the problem. Here is a generic guide on how to remove the spark plugs and how it is done on your car in the images below.

https://www.2carpros.com/articles/how-to-change-spark-plugs

If you want to replace them here is the type

Spark Plug Type .................... GM P/N 12569190

Check out the images (below). Please let us know what happens and please start a new thread on the p0411 code.

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