1990 GMC Sierra hesitation

1990 GMC SIERRA
5.7L • V8 • 2WD • AUTOMATIC
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JAMES1973
  • MEMBER
  • 1 POST
when the motor warms up and I reach 35-40 mph the truck hesitates as if it was running out of gas.
It only happens in overdrive. If I let drop below 35 or go above 40 it drives fine. No codes and it has a TBI carb.
May 13, 2014 at 10:15 PM
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HMAC300
  • ✓Experienced Mechanic
  • 48,601 POSTS
these like to blow the gasket under tbi so check for that as it would be a massive vacuum leak. also check for soft hoses leading to map sensor and pcv valve. check fuel pressure 9-11 psi
May 13, 2014 at 11:21 PM
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