RepairPal is your advocate for car care advice and guidance

Q: what is going on with truck.. rough idle. BAD gas mileage. cranks before start on 1998 Chevrolet 1500 Pickup

My check engine light has been on for 5 years (minor evap leak)NO problems with truck during that time. Moved from NY to NC. Had truck tuned up and oil changed before the move. Got here oil was over full. No other problems. Changed oil once again. 2 months after move truck idles rough. Tried injector cleaner.Nope.. no fix.. BUT now check engine light is OFF. Called mechanic cause I broke a brake line. He fixed line and looked at rough idle problem. Plugs were a mess. Some carbon, some covered in oil, some brown in color. Oil over full again (NO gas smell to oil however) Changes spider injecter, changes plugs. Calls it done. NOPE.. still idles rough and gas mileage hits rock bottom, and trucks STINKS of fuel. Called mechanic again.Broken gas line. Mechanic fixes line and says all good once again. NOPE.. Still ideling rough, gas mileage still HORRIBLE, AND now for the first time ever,truck cranks and cranks before starting BUT only intermittently. No specific time when it will happen. Sometimes when cold, and other times when it has run for a short time. Check engine light still out at this point.Truck was hard starting again, and I stepped on accelerator to get it going. Check engine light is back ON but truck starts. Get truck home, shut it off and try starting it immediately..Starts fine, no cranking at all. Called the mechanic again. Checks with computer and error code says minor evap leak. Finds loose connection to map sensor. Blames the problem on the difference between fuel between NY and NC. Resets check engine light and calls it good once again. NOPE.. Truck still idles rough and will crank before starting once again. Neighbor says ask here about map sensor, erg valve, fuel pump relay, o2 sensor,throttle body sensor and ask for suggestions before calling mechanic again.
Get a Repair Estimate
Guaranteed by certified locations nationwide. Learn more
RepairPal estimates are guaranteed at over 1,700 quality certified locations nationwide. Learn more
Didn't find what you were looking for?