Engine surge from 600 rpm to 1500 rpm ?

This problems are very much noticed on vehicles, cars,trucks,jeeps of all models and brands.
The possibilities are either a vacuum leak or fuel issue.
You need to get this tested to confirm the problem.
Have a reputable shop conduct two tests.A "smoke test" (to check for vacumm leaks) and a fuel pressure test (to make sure the fuel pressure regulator is operating correctly). In most of cases its vacumm leak.But then you should get a P series code for a lean condition.

This details will help.

For more car related problem troubleshooting:---

This are the sections, you can go through and click the link to read its troubleshooting.

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The car will not start?

http://schematicsdiagram.blogspot.com/2011/06/car-will-not-start.html

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Car will not crank?

http://schematicsdiagram.blogspot.com/2011/06/car-will-not-crank.html

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Car has no spark?

http://schematicsdiagram.blogspot.com/2011/06/car-has-no-spark.html

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How to troubleshoot car battery?

http://schematicsdiagram.blogspot.com/2011/06/how-to-troubleshoot-car-battery.html

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How to test starter solenoid?

http://schematicsdiagram.blogspot.com/2011/06/how-to-test-starter-solenoid.html

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How to test cars starter?

http://schematicsdiagram.blogspot.com/2011/06/how-to-test-cars-starter.html

How to replace starter in car?

http://schematicsdiagram.blogspot.com/2011/06/how-to-replace-starter-in-car.html

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car will turn over but will not start?

http://technoanswers.blogspot.com/2011/05/car-will-turn-over-but-will-not-start.html

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Car wont start?

http://howtobyme.blogspot.com/2011/10/car-wont-start.html

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