Q: My car hesitates when accelerating, specially uphill

asked by on August 04, 2017

Engine Light is on. It came on after visiting some amateur mechanic shop. My car just in the last week or so started off with issues of power going uphill. I also noticed this as the car would shift into the 2nd gear. The shift wasn't rough but when it did change gear it was very sluggish. And it eventually started to hesitate but not that much.

Now the car is very sluggish going uphill with obvious and frequent hesitations. It's at its worst when the car has been running or HOT. In the morning car is not 100% but worsens as you drive it.

I also noticed BLACKISH smoke coming out of the exhaust. The black exhaust is not coming out all the time. It comes out right after when the car experiences the difficulty trying to go uphill or shift in gears.

I've replaced: spark plugs, sp-wires, d-cap rotor, cleaned the d-cap, new MAF, IAC, O2 sensor.

*distributor cap does have a lot oil built up underneath it where there is a metal tray
My car has an automatic transmission.

Loss of power Inspection $79.99 - $99.99 Get a Quote

Hello, thank you for writing in. One of the most common reasons for black smoke and a loss of power is a rich air-fuel mixture. With the check engine light on, have the vehicle scanned for diagnostic codes. This can be done at most automotive parts stores, or by a technician. Use any codes present to help you determine what sensor has failed, or what the computer has detected as being the issue. Take any corrective action from there. If no codes are present, you will want to look into the fuel system first. From fuel pump and pressure, to the fuel filter (which may need to be replaced), and onto the fuel injectors should all be inspected for proper function. The main computer systems (ECU) can also cause miscalculations with the air-fuel ratio and may need to be looked at as well. If you would like more help finding and resolving the issue, contact our service department.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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