Q: Bucking and sputtering upon startup on 1999 GMC K1500 Suburban

asked by on August 16, 2016

My car has 180,000 miles. It developed some starting problems. It doesn't matter if I start it when the engine is cold or warmed up, it would start bucking and sputtering. This would last in the first several minutes upon startup. It would keep running like this and if I attempted to accelerate fast, the car would start revving high. After several minutes of running rough, it would get back to normal. Each startup is like this. What might be the cause of this problem?

Hello. Thanks for writing in about your 1999 GMC K1500 Suburban. It is likely a faulty/dirty idle air control valve, a faulty mass airflow sensor or bad coil pack causing your issue. If you would like to have this looked at, a certified professional from YourMechanic can come to your car’s location to inspect the starting issue and let you know what should be done.

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