Having problems with your 1990 GMC Sierra ?
My 1990 GMC truck K1500 · Engine: 5.7L V8 TBI has no power or loose power going up hills and suggestions
Sound like it could be a clog fuel filter, have you check it, if not remove and check to see if it's clog, replace it if bad, fuel filter is under your truck, on drives side, on inner frame rail.
Repair Help & Product Troubleshooting for 1990 GMC Sierra
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