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Q: Difficulty starting, hesitates when gas is applied - 1973 Pontiac Ventura

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The car had original parts when I purchased it. Since then, I had the 2bbl carburetor replaced with a 4bbl. I also installed a dual exhaust and replaced the intake manifold. I had the spark plugs replaced, along with the wires, coil, rotor and distributor cap. Afterwards, I've noticed that the plugs are being fouled. The plugs that are furthest and closest to the firewall on the driver's side, have been fouled out. Also, two inner plugs on the passenger's side are also being fouled out. Due to this, the car starts with difficulty. It also starts hesitating when I apply the gas pedal. How can I fix this?

Hello there, thanks for your question. You may have a few different things going on with your 1973 Pontiac Ventura. When you upgraded from the 2bbl to a 4bbl, you increased the amount of fuel the engine is getting. Given that you have added more fuel, it is likely the engine needs to be tuned and the timing needs to be adjusted. Alternatively, you could possibly have an intake leak. Either way the engine is running rich or oil is leaking onto the spark plugs. Considering having a certified automotive technician such as one from YourMechanic inspect your car issue and perform any repairs as needed.

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