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RPM Surging at Constant Speed

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Old May 1, 2012 | 05:29 PM
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rd_ls1_z's Avatar
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From: NWFL, AKA - Redneck Riviera
Default RPM Surging at Constant Speed

At constant speed, my truck (2008 Silverado) surges a couple hundred RPM, which occurs with AC compressor on or off, and with cruise control on or off. I've noticed that the TPS jumps slightly, followed by injector duty cycle, MAP and MAF also. The MAP continues on an upward trend until it reaches about 95 to 100 kPa before it drops to "normal," which is when the surge stops. Also, it looks like bank 1 O2 is reading rich. The only modifications done to the truck are K&N filter, Magna Flow Cats and Cat back exhaust. I have the picture of the EFI Scan attached.

Thanks for any help.
Attached Thumbnails RPM Surging at Constant Speed-sensors.jpg  
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