1997 Chevy Cheyenne Rough acceleration after replacing with

1997 CHEVROLET CHEYENNE
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KYREBELYELL2004
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Engine Performance problem
1997 Chevy Cheyenne 6 cyl Two Wheel Drive Automatic

Hello, i have a 1997 chevy 1500 truck. Just rebuilt the 4.6L vortec in it and replaced with an older model crank. I now have great ideling but rough acceleration. the truck can get to about 70 after it goes through the shifting of gears and what not. could this problem be related to the crank? i know the older model cranks dont have the crank case sensors that the newer models have. do you think this is the problem with my poor acceleration? if so, could i just replace the computer with an older computer and it run fine?
Jun 14, 2009 at 5:26 PM
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RACEFAN966
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You need to put the proper crank in it with the exciter ring on it for the crank position sensor to read. So I would call and get a price on a reground crank with the bearings.
Jun 15, 2009 at 1:58 PM
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KYREBELYELL2004
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thanks for the fast input, but could i not just change the computer to a computer out of a 94 chevy or so, and it run just fine?
Jun 15, 2009 at 3:47 PM
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RACEFAN966
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You can try to change computers but the two systems are completely different. One has throttle body injection and the other has multi port injection and is a vortec engine. 94 uses 15 psi fuel pressure the 97 used 55-65 psi fuel pressure. The 94 is an OBD1 system and the 97 is an OBD2 system they are just not the same. Sorry the only correct fix is the right crank.
Jun 16, 2009 at 10:02 AM