What causes a car to idle good and run rough when you give it gas?
Vacuum leek
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i think it causes bad/rough idle
MAF senso, or transmission fluid.
You broke it. Way to go.
check dist. cap for water
There are several things that can cause your 2004 Chevrolet Trailblazer to idle rough. The most common causes are a dirty fuel filter or a dirty air filter.
This depends on the temperature outside and if your starting it cold. If you start it cold even in 60 degree weather it may idle rough for the first few minutes. You can solve this by letting the Wait to Start light to go out and then pressing the Throttle down slightly and letting off. This engages the high idle which should stop your vehicle from running rough for so long, as it lets the engine warm up faster.
injectors are a common problem
Could be the TPS, it will cause it to idle high and low and make the car become sluggish, but a vehicle will run without one, but it will run very rough.
The usual idle RPM for a diesel engine typically ranges between 600 to 800 RPM, depending on the engine design and application. In some heavy-duty diesel engines, the idle speed may be set slightly higher, around 900 RPM, to ensure proper lubrication and cooling. It's essential to consult the manufacturer's specifications for the exact idle RPM for a specific engine model.