1988 Chevy Truck emissions

1988 CHEVROLET TRUCK
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AARONGARNER
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  • 1 POST
Engine Performance problem
1988 Chevy Truck V8 Four Wheel Drive Automatic 255k miles

I have a 1988 chevy 2500 with a newer professionaly rebuilt longblock 350 4bolt main. new cat as of 2 years ago. new plugs cap rotor air filter replaced after failing emissions. to no avail.first test
hc ppm co%
cruise lim 200 1.5
cruise emis 110 .32
pass pass
idle lim 220 1.2
idle emis 290 .51
fail pass
second test after replacing cap rotor plugs air filter
hc ppm
cruise lim 200 co%1.5
cruis emis 106 0.3
pass pass
idle lim 220 1.2
idle emis 292 .57
fail pass
Jun 30, 2010 at 7:22 PM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
if you have any exaust leaks, then you won't pass emissions. But usually the guy running the test would say so. What you can do is change yoru oil and oil filter then drive the truckat least 10 miles on the exspressway. then take it in for testing, that lets the engine heat up sufficently and get rid of excess hyrdocarbons. try that and see if you pass then...
Jul 10, 2010 at 2:25 PM
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