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1996 CHEVROLET SUBURBAN
134,000 MILES • V8 • 4WD • AUTOMATIC
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LUCYLOU1429
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  • 1 POST
just bought a 1996 chevrolet suburban k2500 with vortec 7.4 v8, i have check and there are no codes in the system, diagnostics have required that both o2 sensors(up stream), icm, and map sensor be replaced,...my problem is that every time the vehicle is started the start idle starts at 1800-2000rpm,...most the time is will settle to 600-800 rpm but sometimes it will sit at 1000rpm til it is driven a short distance,...i have checked for vacuum leaks, replaced the iac and have also replace the egr gasket when removed and cleaned,...the vehicle runs great except for the starting high idle...
May 22, 2008 at 6:39 PM
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MERLIN2021
  • ASE Certified Mechanic
  • 17,250 POSTS
  • ASE Certified Mechanic
An Ohm meter across the engine coolant temp sensor will reveal a bad one, Cold it should read over 100,000 ohms hot 177 ohms.

This guide can help

https://www.2carpros.com/articles/engine-idles-too-high


Please go over this guide and report back.


May 23, 2008 at 1:10 PM
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